JWT Z32 MAF Chip is in - problems? (long)
12-19-2004, 03:07 PM
#41
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Actually - we tried something and it's very interesting....
We decided just to go for a drive. Damned the consequences.
So we drove around on the freeway - car now does not buck at all like it did the other day once the car is warmed up. However, on cold start it's still hosed.
And in mid-range I feel hesitation, but not the bucking I was getting, just slight hesitation.
Anyone else out there with this setup feel any bog at mid RPM? At high RPM it feels fine and it's idling somewhat normal now when warmed up.
We also tried disconnecting the ground from the Tomei connector to the battery while doing this and found no difference in how the car ran.
Last question - has anyone here done any NProbe testing or any testing at all looking at your idle timing? Is yours steady or does it variate? I noticed while driving that if I was moving and popped the car into N, the timing would stick on 15 perfectly. As soon as I stopped the car however, it would fluctuate a lot between 7-15.
It seemsl ike things are better now for some unknown reason - but I can't figure out why. And they still aren't fixed. The midrange bog really sucks on the power.
We decided just to go for a drive. Damned the consequences.
So we drove around on the freeway - car now does not buck at all like it did the other day once the car is warmed up. However, on cold start it's still hosed.
And in mid-range I feel hesitation, but not the bucking I was getting, just slight hesitation.
Anyone else out there with this setup feel any bog at mid RPM? At high RPM it feels fine and it's idling somewhat normal now when warmed up.
We also tried disconnecting the ground from the Tomei connector to the battery while doing this and found no difference in how the car ran.
Last question - has anyone here done any NProbe testing or any testing at all looking at your idle timing? Is yours steady or does it variate? I noticed while driving that if I was moving and popped the car into N, the timing would stick on 15 perfectly. As soon as I stopped the car however, it would fluctuate a lot between 7-15.
It seemsl ike things are better now for some unknown reason - but I can't figure out why. And they still aren't fixed. The midrange bog really sucks on the power.
12-19-2004, 04:57 PM
#43
One thing I notice when watching NProbe is if the car idles in neutral with the car running, timing stays flat on 15. But as soon as the car came to a stop, the timing started fluctuating. I'm curious if those with emanage, or NProbe do a quick logging of thier timing at idle when cold and warm....it'd be nice to have a comparison.
S
S
12-19-2004, 05:47 PM
#44
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The question is, Bags, at a dead stop does it fluctuate in timing or does it stay steady at 15?
Did some more driving - as long as the car is warmed up it feels pretty good....except for the occassional (happens 1/4 of the time) I get hesitation at 3500-4500RPM.
I also notice if I push in the clutch after boosting and let off the throttle compltely, the car almost stalls. Under normal driving, it doesn't do that. I expect that is simply a little blowback from the TB closing, and the Z32 MAF is more sensitive to such things.
I was going to put the A32 MAF and A32 JWT Chip in and see if I get the hesitation, but since the hesitation I'm getting almost seems to be healing itself, and I want to wait a few hours and try another cold start on the Z32 MAF - I'll test that next weekend.
I had just regapped my plugs before all of this, and I'm wondering if that's my problem. I gapped to .035. Although I drove for 1 day like that with the A32 ECU/MAF, and don't remember feeling any hesitation.
But for now, as long as I can get it past the nasty cold start, it runs fairly well. I'm not seeing anything on the NProbe when the hesitation occurs either - which is strange.
Did some more driving - as long as the car is warmed up it feels pretty good....except for the occassional (happens 1/4 of the time) I get hesitation at 3500-4500RPM.
I also notice if I push in the clutch after boosting and let off the throttle compltely, the car almost stalls. Under normal driving, it doesn't do that. I expect that is simply a little blowback from the TB closing, and the Z32 MAF is more sensitive to such things.
I was going to put the A32 MAF and A32 JWT Chip in and see if I get the hesitation, but since the hesitation I'm getting almost seems to be healing itself, and I want to wait a few hours and try another cold start on the Z32 MAF - I'll test that next weekend.
I had just regapped my plugs before all of this, and I'm wondering if that's my problem. I gapped to .035. Although I drove for 1 day like that with the A32 ECU/MAF, and don't remember feeling any hesitation.
But for now, as long as I can get it past the nasty cold start, it runs fairly well. I'm not seeing anything on the NProbe when the hesitation occurs either - which is strange.
12-19-2004, 08:05 PM
#45
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Looking at the Nprobe data, the Z32 MAF and A32 MAF have pretty much the exact same voltage at idle.
So why would cold starts be all screwed up on the Z32 MAF and not the A32 MAF?
That's what I'm trying to solve now.....
So why would cold starts be all screwed up on the Z32 MAF and not the A32 MAF?
That's what I'm trying to solve now.....
12-20-2004, 08:28 AM
#46
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Actually, if anyone out there has any sort of datalogging equipment (NProbe, Auterra, etc) and the Z32 MAF/JWT ECU (Stephen, delio, etc) then I'd LOVE to see startup data on a cold morning.
I have my data in xls format and if anyone wants to take a look and help me analyze it, let me know and I'll E-Mail it to you or put it up on my site for download.
IanS
I have my data in xls format and if anyone wants to take a look and help me analyze it, let me know and I'll E-Mail it to you or put it up on my site for download.
IanS
12-20-2004, 08:41 AM
#47
Originally Posted by iansw
Actually, if anyone out there has any sort of datalogging equipment (NProbe, Auterra, etc) and the Z32 MAF/JWT ECU (Stephen, delio, etc) then I'd LOVE to see startup data on a cold morning.
I have my data in xls format and if anyone wants to take a look and help me analyze it, let me know and I'll E-Mail it to you or put it up on my site for download.
IanS
I have my data in xls format and if anyone wants to take a look and help me analyze it, let me know and I'll E-Mail it to you or put it up on my site for download.
IanS
12-20-2004, 11:42 AM
#49
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I sent the data to JWT - they didn't seem super enthused about it.
When I told him the A32 MAF works fine at idle with the Z32 EEPROM, he told me that was impossible.
Well - if it's impossible, why is it doing it!?
(It's not impossible, since voltage at idle is relatively the same on the Z32 and A32 - but he wouldn't listen.)
When I told him the A32 MAF works fine at idle with the Z32 EEPROM, he told me that was impossible.
Well - if it's impossible, why is it doing it!?
(It's not impossible, since voltage at idle is relatively the same on the Z32 and A32 - but he wouldn't listen.)
12-20-2004, 01:31 PM
#51
Originally Posted by iansw
The question is, Bags, at a dead stop does it fluctuate in timing or does it stay steady at 15?
I should have my OBD2 reader back in a few days, I'll try and give you a solid answer.. maybe that will help some
And on the JWT convo.. that is crap... they should have either told you to send them the prom back for testing or sent you a new prom
12-20-2004, 07:54 PM
#52
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Did some more testing tonight.
I decided to try the A32 EEPROM with the Z32 MAF just for ***** and giggles. Plugged the NProbe in and started her up. Car was already warm from the drive home, so I didn't get to test cold start.
Interestingly, the timing was ROCK STEADY at 5 at idle!
maximase86 tells me that is WAY too low (says it hsould be 15).
Maybe it is too low, but the car idles PERFECTLY.
It does go to 15 in timing when pushing in the clutch and coasting.....
Anyway, so I took it for a drive - I could tell I was running lean instantly, so I limped back home. The Z32 MAF does not like that chip under load, but loves it at idle.
I also tested with the old configuraiton - A32 ECU and A32 MAF.
The car runs very well, just like I suspected.
Once again, timing 5 at idle, 15 when coasting to a stop.
So until I figure this out, I'm sticking with the old configuraiton because it's a lot easier after work and in the morning to deal with rather than waiting 20 minutes for the car to be able to move.
Another note - with Z32 MAF and Z32 EEPROM, the timing bounces between 7-13 and sometimes takes a big jump to 18-20 at idle.
It alos sticks steady at 15 however when coasting.
I cut and pasted all the important data ranges from the NProbe files and made descriptive Excel sheets showing what I mean. Unfortunately, the colo that runs my site is down (Again!) so as soon as it's up I'll post a link to the files.
IanS
I decided to try the A32 EEPROM with the Z32 MAF just for ***** and giggles. Plugged the NProbe in and started her up. Car was already warm from the drive home, so I didn't get to test cold start.
Interestingly, the timing was ROCK STEADY at 5 at idle!
maximase86 tells me that is WAY too low (says it hsould be 15).
Maybe it is too low, but the car idles PERFECTLY.
It does go to 15 in timing when pushing in the clutch and coasting.....
Anyway, so I took it for a drive - I could tell I was running lean instantly, so I limped back home. The Z32 MAF does not like that chip under load, but loves it at idle.
I also tested with the old configuraiton - A32 ECU and A32 MAF.
The car runs very well, just like I suspected.
Once again, timing 5 at idle, 15 when coasting to a stop.
So until I figure this out, I'm sticking with the old configuraiton because it's a lot easier after work and in the morning to deal with rather than waiting 20 minutes for the car to be able to move.
Another note - with Z32 MAF and Z32 EEPROM, the timing bounces between 7-13 and sometimes takes a big jump to 18-20 at idle.
It alos sticks steady at 15 however when coasting.
I cut and pasted all the important data ranges from the NProbe files and made descriptive Excel sheets showing what I mean. Unfortunately, the colo that runs my site is down (Again!) so as soon as it's up I'll post a link to the files.
IanS
12-20-2004, 09:47 PM
#54
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Thanks for the offer bro - but my site's back up now.
http://www.cyberhub.net/jwt/
All files are in there - Eric Johnson also gave me a file to compare - appears timing of 5 at idle isn't abnormal with the JWT ECU.
So the truth is now that the car idles perfectly with the Z32 MAF and A32 MAF with the A32 Chip. And the A32 MAF idles perfect with the Z32 Chip.
Just take a look guys and tell me if anything stands out at you.
The COLDSTART one is the really messed up one. I'm going to do a comparative one with the A32 Chip and MAF first thing in the morning.
http://www.cyberhub.net/jwt/
All files are in there - Eric Johnson also gave me a file to compare - appears timing of 5 at idle isn't abnormal with the JWT ECU.
So the truth is now that the car idles perfectly with the Z32 MAF and A32 MAF with the A32 Chip. And the A32 MAF idles perfect with the Z32 Chip.
Just take a look guys and tell me if anything stands out at you.
The COLDSTART one is the really messed up one. I'm going to do a comparative one with the A32 Chip and MAF first thing in the morning.
12-20-2004, 11:14 PM
#57
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So I'm lying awake in bed thinking on this some more.
And had this thought:
It's not definitive that the problem is the ECU. The one thing I haven't tried is a cold start (car sitting for 4+ hours) with the Z32 MAF and the A32 EEPROM.
If that acts up like the Z32 EEPROM does with that MAF, then that tells me that there is a problem with the element on the MAF possibly heating up very slowly or having a problem with cold air?
I dunno - just throwing ideas out - I can't sleep.
I won't have time to test this in the morning, unfortunately - it's going to have to wait a few days...if this is even a viable test....
And had this thought:
It's not definitive that the problem is the ECU. The one thing I haven't tried is a cold start (car sitting for 4+ hours) with the Z32 MAF and the A32 EEPROM.
If that acts up like the Z32 EEPROM does with that MAF, then that tells me that there is a problem with the element on the MAF possibly heating up very slowly or having a problem with cold air?
I dunno - just throwing ideas out - I can't sleep.
I won't have time to test this in the morning, unfortunately - it's going to have to wait a few days...if this is even a viable test....
12-21-2004, 08:52 AM
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I was planning on asking him tomorrow - he works for me, so it will directly affect his performance review. . But with how well the car runs when warm, I don't think it's the MAF either....or at least definatley not the wiring now that I've got it soldered tightly.
I think it's the cold start program on the Z32 EEPROM. But then again, the A32 MAF starts fine on cold start with the Z32 EEPROM....so
However, another test I will be doing because I know the car idles well with EITHER MAF when warm with the A32 EEPROM, is to put the Z32 MAF in with the A32 EEPROM and do another cold start after the car sits overnight. If it runs crappy then, then it would be the MAF - it has a problem with cold starts......<The A32 MAF however doesn't like the Z32 EEPROM under load - which is what I expect>
I won't have time to do that test for a few days however.
The more I think about it as I'm typing - I really don't know if it's the MAF or the chip at the moment - I'm 50% 50% on it.
. But with how well the car runs when warm, I don't think it's the MAF either....or at least definatley not the wiring now that I've got it soldered tightly. I think it's the cold start program on the Z32 EEPROM. But then again, the A32 MAF starts fine on cold start with the Z32 EEPROM....so
However, another test I will be doing because I know the car idles well with EITHER MAF when warm with the A32 EEPROM, is to put the Z32 MAF in with the A32 EEPROM and do another cold start after the car sits overnight. If it runs crappy then, then it would be the MAF - it has a problem with cold starts......<The A32 MAF however doesn't like the Z32 EEPROM under load - which is what I expect>
I won't have time to do that test for a few days however.
The more I think about it as I'm typing - I really don't know if it's the MAF or the chip at the moment - I'm 50% 50% on it.
12-21-2004, 09:40 AM
#61
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It's a Tomei Connector.
My car is nowhere nearby - But I can assure you I matched them up and it tested perfectly with the voltmeter via the Diagram in the PDF on JWT's site, matching the letters to the "A-F" labeled pins on the Z32 MAF.
I don't remember the wire colors at the moment - but I do have this written down from testing after soldering the joints.
A= 0v
B=.5v (car was off, key turned forward in ACC position)
C= .002 Mv resistance (-12v when Black probe attached to the + on the battery, Red on Harness)
D= .009 MV Resistance (-12v when Black probe attached to the + on the battery, Red on Harness)
E= + 12v
F= 0v
Car runs well when warmed up, and cold start runs well with the A32 MAF and the Z32 EEPROM.
So it's not the wiring - otherwise the car wouldn't run so well with the Z32 MAF and A32 EEPROM at idle when warm.
What I'm thinking it could be is these 2 things:
1) Cold start program on Z32 EEPROM is screwed. - Replace EEPROM
2) MAF Heat Element has a very difficult time heating up when cold - once it does heat up, it's fine - replace MAF
Testing with either another MAF or on cold start with MAF with the A32 Chip should tell me which it is.
Reasoning:
There are 2 objects in this list of changes to the car
1) EEPROM
2) MAF
That would mean 4 total variations to find the problem:
1) Old MAF, old EEPROM - Runs aweosme on cold start.
2) New MAF, new EEPROM - Runs horrible on cold start
3) New EEPROM, old MAF - Runs great on cold start
4) Old EEPROM, new MAF - Haven't tested yet.
At this point I'm trying to be as scientific as possible, eliminating all possibilities by using deductive reasoning.
Let me know if my thinking is flawed.
My car is nowhere nearby - But I can assure you I matched them up and it tested perfectly with the voltmeter via the Diagram in the PDF on JWT's site, matching the letters to the "A-F" labeled pins on the Z32 MAF.
I don't remember the wire colors at the moment - but I do have this written down from testing after soldering the joints.
A= 0v
B=.5v (car was off, key turned forward in ACC position)
C= .002 Mv resistance (-12v when Black probe attached to the + on the battery, Red on Harness)
D= .009 MV Resistance (-12v when Black probe attached to the + on the battery, Red on Harness)
E= + 12v
F= 0v
Car runs well when warmed up, and cold start runs well with the A32 MAF and the Z32 EEPROM.
So it's not the wiring - otherwise the car wouldn't run so well with the Z32 MAF and A32 EEPROM at idle when warm.
What I'm thinking it could be is these 2 things:
1) Cold start program on Z32 EEPROM is screwed. - Replace EEPROM
2) MAF Heat Element has a very difficult time heating up when cold - once it does heat up, it's fine - replace MAF
Testing with either another MAF or on cold start with MAF with the A32 Chip should tell me which it is.
Reasoning:
There are 2 objects in this list of changes to the car
1) EEPROM
2) MAF
That would mean 4 total variations to find the problem:
1) Old MAF, old EEPROM - Runs aweosme on cold start.
2) New MAF, new EEPROM - Runs horrible on cold start
3) New EEPROM, old MAF - Runs great on cold start
4) Old EEPROM, new MAF - Haven't tested yet.
At this point I'm trying to be as scientific as possible, eliminating all possibilities by using deductive reasoning.
Let me know if my thinking is flawed.
12-21-2004, 10:31 AM
#62
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Next thought - could this be caused by the MAF being on the charged side?
I want to verify again - has anyone with this setup gotten it working on the charged side? No FPR, No FMU - just EEPROM, MAF, and SC.....
I want to verify again - has anyone with this setup gotten it working on the charged side? No FPR, No FMU - just EEPROM, MAF, and SC.....
12-21-2004, 10:53 AM
#63
Originally Posted by iansw
Next thought - could this be caused by the MAF being on the charged side?
I want to verify again - has anyone with this setup gotten it working on the charged side? No FPR, No FMU - just EEPROM, MAF, and SC.....
I want to verify again - has anyone with this setup gotten it working on the charged side? No FPR, No FMU - just EEPROM, MAF, and SC.....
I have been running the Z32 maf on the charged side for over a year now, with no problems.
I am using an fmu now, but that is because I am boosting beyond what my 370's can provide at oem fuel pressure.
12-21-2004, 09:46 PM
#65
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Tested cold-start with the Z32 MAF and A32 ECU like I said I would tonight in cold start conditions:
It runs like azz - just like with the Z32 Program. After warmup, it levels off and idles fine.
1) Old MAF, old EEPROM - Runs aweosme on cold start.
2) New MAF, new EEPROM - Runs horrible on cold start
3) New EEPROM, old MAF - Runs great on cold start
4) Old EEPROM, new MAF - Runs horrible on cold start
So that tells me it's the MAF.
If it was just the MAF being on the charged side causing it, you'd think it would cause turbulence and run bad all the time, not just when cold.
I was also considering hot air vs cold air, but with the intake on my passenger side far away from the block and the hood open - and it sitll levels off when warmed up - I can't see how that's it. I don't think the SC being warm with oil affects things very much with the hood open and piping in 40 degree air.
So now I'm thinking the MAF has issues - but it's voltage looks correct at all RPM's, even when cold!.
wtf?
It runs like azz - just like with the Z32 Program. After warmup, it levels off and idles fine.
1) Old MAF, old EEPROM - Runs aweosme on cold start.
2) New MAF, new EEPROM - Runs horrible on cold start
3) New EEPROM, old MAF - Runs great on cold start
4) Old EEPROM, new MAF - Runs horrible on cold start
So that tells me it's the MAF.
If it was just the MAF being on the charged side causing it, you'd think it would cause turbulence and run bad all the time, not just when cold.
I was also considering hot air vs cold air, but with the intake on my passenger side far away from the block and the hood open - and it sitll levels off when warmed up - I can't see how that's it. I don't think the SC being warm with oil affects things very much with the hood open and piping in 40 degree air.
So now I'm thinking the MAF has issues - but it's voltage looks correct at all RPM's, even when cold!.
wtf?
12-21-2004, 10:12 PM
#66
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Was just looking at more data.
On cold start, at 850 RPM the Z32 MAF reads 1.5v at idle
idle then drops to 500, but MAF reads 1.55 then.
Then it recovers some and idle goes back to about 750 at 1.35v
Then more of this up/down ensues.
On Cold start, at 850 RPM the A32 MAF reads 1.29v at idle...any variation up or down and it changes linearly from there.
would this cause what I'm seeing? I know it's only .2v, but it seems to maybe indicate my problem.
Maybe the filament in the MAf is having a hard time registering for a few minutes?
I'm just throwing out crap here.....anyone?
On cold start, at 850 RPM the Z32 MAF reads 1.5v at idle
idle then drops to 500, but MAF reads 1.55 then.
Then it recovers some and idle goes back to about 750 at 1.35v
Then more of this up/down ensues.
On Cold start, at 850 RPM the A32 MAF reads 1.29v at idle...any variation up or down and it changes linearly from there.
would this cause what I'm seeing? I know it's only .2v, but it seems to maybe indicate my problem.
Maybe the filament in the MAf is having a hard time registering for a few minutes?
I'm just throwing out crap here.....anyone?
12-22-2004, 05:08 AM
#68
Is your BOV venting air at idle? If so tighten it down as much as you can so as little air as possible escapes. Even though the BOV is before the MAF the venting can cause issues, especially when their is a rough idle, low vacume pulsing will cause the BOV at idle on a SC car to open and close a bit and exegarate the problem. I had this same experiance developing my larger piping and Pathfinder TB set up on my old set up. Clamping the adjustment bolt on the BOV down allot cured it.
Are your throttle body coolant lines still hooked up?
Perhaps you need to play with the set screw adjustment for how open or closed the TB plate is at rest?
Are your throttle body coolant lines still hooked up?
Perhaps you need to play with the set screw adjustment for how open or closed the TB plate is at rest?
12-22-2004, 05:50 AM
#69
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Mardi -
I have the HKS SSQ BOV - by the way it is designed, it is supposedly impossible for it to vent air under even 1Hg Vacuum. It is also tightened down all the way anyway because I was testing that the other day and found that it didn't help.
Coolant lines are still hooked up, yes....Would that be an issue?
The car works so perfectly with the A32 MAF (idle/MAF voltage is DEAD ON at 650 when warm, and starts pefect at 1500 when cold then drops very linearly until warm) that I don't htink the TB Plate is any kind of issue. How would this affect the car only on warm-up?
I'm going to try rigging the MAF on the non-charged side this weekend and see what I get.
My co-worker with the Z starts his shift today - I'll ask him if I can borrow his MAF - although I have a sneaking suspicion that isn't going to change anything, since i've already tested this MAF on his car and it ran perfectly....
I have the HKS SSQ BOV - by the way it is designed, it is supposedly impossible for it to vent air under even 1Hg Vacuum. It is also tightened down all the way anyway because I was testing that the other day and found that it didn't help.
Coolant lines are still hooked up, yes....Would that be an issue?
The car works so perfectly with the A32 MAF (idle/MAF voltage is DEAD ON at 650 when warm, and starts pefect at 1500 when cold then drops very linearly until warm) that I don't htink the TB Plate is any kind of issue. How would this affect the car only on warm-up?
I'm going to try rigging the MAF on the non-charged side this weekend and see what I get.
My co-worker with the Z starts his shift today - I'll ask him if I can borrow his MAF - although I have a sneaking suspicion that isn't going to change anything, since i've already tested this MAF on his car and it ran perfectly....
12-22-2004, 08:35 AM
#70
I don't think it's the BOV or anything like that, since it runs fine with the other MAF and either chip.
Those voltages for the Z32 MAF don't sound right and I'd think even a 0.2V difference at idle could be significant, but depends on the shape of the MAF voltage curve I'd guess. Bernard can probably elaborate.
Those voltages for the Z32 MAF don't sound right and I'd think even a 0.2V difference at idle could be significant, but depends on the shape of the MAF voltage curve I'd guess. Bernard can probably elaborate.
12-22-2004, 08:38 AM
#71
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Looks like the curve is pretty jagged at idleo n cold start.....
I hope my co-worker (schuss on this board who used to own a 2000 Maxima) loans me the MAF from his Z (he doesn't drive it in the winter anyway) and then I can test further.
I hope my co-worker (schuss on this board who used to own a 2000 Maxima) loans me the MAF from his Z (he doesn't drive it in the winter anyway) and then I can test further.
12-22-2004, 09:05 AM
#72
Yeah, I'm thinking that's it now. The voltage should go up as RPM goes up, not necessarily linear, but definitely not like what you're describing. It should act exactly like the A32 MAF, but slightly lower at same RPM.
12-22-2004, 12:53 PM
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Another interesting note - If you look at the "coldstart" Excel sheetso n my site, you can see the voltage the car reads the MAF at before I start the engine in the first few lines....
The A32 MAF reads .17-.18, and the Z32 reads .42....don't know what this means, but it's interesting.
Ice, when you say "I htink that's it" what do you mean exactly? I guess I'm just not following you.
The A32 MAF reads .17-.18, and the Z32 reads .42....don't know what this means, but it's interesting.
Ice, when you say "I htink that's it" what do you mean exactly? I guess I'm just not following you.
12-22-2004, 01:21 PM
#74
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Uhhhhhhhh.
I was just re-reading my notes.
I forgot my earlier post where I said the Stock 97 MT ECU worked fine with the Z32 MAF. I also remember it working well in Sept. when I used that setup to pass emmissions.
Can't be the MAF.
I was just re-reading my notes.
I forgot my earlier post where I said the Stock 97 MT ECU worked fine with the Z32 MAF. I also remember it working well in Sept. when I used that setup to pass emmissions.
Can't be the MAF.
12-22-2004, 01:52 PM
#75
ie...just brainstorming. I was pretty sure it was the wiring, but you say you've done it properly. Next guess, since you've been through two chips is the Z32 MAF unless JWTs program is indeed corrupt or wrong for your particular ECU.
Do you know anybody else locally with a JWT ECU?
Do you know anybody else locally with a JWT ECU?
12-22-2004, 02:05 PM
#76
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Well, since the A32 EEPROM AND Z32 EEPROM both don't work with the Z32 MAF, I was sure it was the MAF. How could BOTH ECU's be misprogrammed? Also - the Z32 MAF + Z32 EEPROM works very well once the car is fully warmed up - it's allowing far more fuel in up high. The Z32 MAF + A32 EEPROM also works fine when warmed up - but I can tell it's running lean, so I didn't boost. So how can it be the chip if the chip works so well when warm?
But since it works with the 97 stock MT ECU, then it can't be the MAF - or the wiring.
SO I'm at a loss here - I can't figure out what it oculd be.
It looks like it's not the MAF
It looks like it's not the EEPROM
UNLESS the ECU has a totally different program for cold start - which means they put the A32 Cold-Start program on the Z32 Chip?
But since it works with the 97 stock MT ECU, then it can't be the MAF - or the wiring.
SO I'm at a loss here - I can't figure out what it oculd be.
It looks like it's not the MAF
It looks like it's not the EEPROM
UNLESS the ECU has a totally different program for cold start - which means they put the A32 Cold-Start program on the Z32 Chip?
12-22-2004, 02:54 PM
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Sorry man - just frustrated and JWT isn't being very helpful - they just insist it's my car and not their program. They tell me there's NO WAY the A32 MAF would work with the Z32 Chip and get angry at me when I try to tell them it does.
FP is 43 at idle when warming up - then drops to 40 when warmed up - same with the A32 MAF and A32 Chip....The A32 MAF also works with the Z32 Chip, so I had assumed that rules out FP as a problem, as it's the same with the A32 MAF on the 2 chips (idles great)
IanS
FP is 43 at idle when warming up - then drops to 40 when warmed up - same with the A32 MAF and A32 Chip....The A32 MAF also works with the Z32 Chip, so I had assumed that rules out FP as a problem, as it's the same with the A32 MAF on the 2 chips (idles great)
IanS
12-22-2004, 03:42 PM
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I spoke with Ben at JWT - he's going to pass the data on to the engineers and try to see what he can do.
Looks like they're listening now. I hsould be getting a call back tomorrow - then they're closed for a week.
Looks like they're listening now. I hsould be getting a call back tomorrow - then they're closed for a week.
12-22-2004, 03:46 PM
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Tlaked to Ben at JWT again.
He seems pretty convinced that the Z32 MAF being on the charged side would cause this....
Is it possible those that have gotten the MAFs working on the charged side had a newer less sensitive version of the Z32 MAF? (Mine I believe is from a 91 300zx)
He seems pretty convinced that the Z32 MAF being on the charged side would cause this....
Is it possible those that have gotten the MAFs working on the charged side had a newer less sensitive version of the Z32 MAF? (Mine I believe is from a 91 300zx)