The new "ben's ecu mod"

[mzmtg]

Gosh the things I do for you people. Ok, in no way do I condone breaking any laws. I figured out how to get rid of the speed limiter on the 4th gen. Cheston & Nick, would you mind putting this in your how-to sections??

Now for the write up:

________________________________

4th Gen Maxima Speed Limiter Removal

The ECU monitors the transmission mounted speed sensor to determine vehicle speed. When the vehicle speed limit is reached, the ECU cuts the fuel flow to the engine to slow the car.

The signal path for the vehicle speed sensor is as follows:

Sensor to Speedometer
Speedometer to ECU & Cruise Control

If the signal is interupted at the actual connection to the ECU, speedometer, odometer and cruise control functions are preserved. The ECU does not recieve a vehicle speed signal, therefore it will not limit the vehicle speed.

This modification is easy. But beware, it does include mutilation of the factory ECU wiring harness...not for the sqeamish.

1.Disconnect negative battery terminal.
2.remove ECU cover from passenger side footwell.
3.Loosen bolt in center of main ECU connector.
4.Unplug main ECU connector.
5.Remove snap-on plastic cover from ECU connector.
6.Locate PINK wire with BLUE stripe. (this wire is located on the right half of the connector when plugged in)
7.Cut PINK/BLUE wire.
8.Reassemble ECU connection.
9.Reconnect negative battery terminal.
10.Drive 140mph.

This modification will cause the "check engine" light to illuminate. If you check the codes, you will get 0104 (Vehicle speed sensor fault) and 0504 (A/T conrtrol unit fault). So far there have been no drivability problems
associated with this mod.

Enjoy.


::stands up to accept accolades from max drivers around the world::

[Sprint™]

I actually did that with a switch.. but i was being selfish .. Haynes Manual Chapter 12

[mzmtg]

Originally posted by SprintMax
I actually did that with a switch.. but i was being selfish .. Haynes Manual Chapter 12

Well damn.

[Sprint™]

well i wasn't being selfish to a sense..

i thought everyone was going to be happy with this http://www.performanceix.com/how-to/...ma_limiter.asp

but still.. nice work Ben...

Originally posted by mzmtg


Well damn.

[Whitemax]

Well, I say, GOOD JOB!!!! Sounds good, plus the speedo will still work. did the check engine light go away?

[mzmtg]

Originally posted by SprintMax
well i wasn't being selfish to a sense..

i thought everyone was going to be happy with this http://www.performanceix.com/how-to/...ma_limiter.asp

but still.. nice work Ben...

Well, that was my point. Using this new method, the speedo still works. This is more of a permanent thing. Well, it's permanent for those of us who drive around with the check engine light on all the time anyway.

I reset the light and drove around some more and it hasnt come on again. It might, it might not.

[Ryan93SE]

hope this one doesnt catch fire......just kidding Ben
good job...i wish i could think of these things

[Sprint™]

the reason i used the switch on the ECU is that i can trip it for a couple secs.. but not long enough to trip the CE Light

Originally posted by mzmtg


Well, that was my point. Using this new method, the speedo still works. This is more of a permanent thing. Well, it's permanent for those of us who drive around with the check engine light on all the time anyway.

I reset the light and drove around some more and it hasnt come on again. It might, it might not.

[mzmtg]

Originally posted by SprintMax
the reason i used the switch on the ECU is that i can trip it for a couple secs.. but not long enough to trip the CE Light

So your is on the ECU or the tranny? I was thinking of doing exactly that, putting a switch in at the ECU end of the thing.

[Sprint™]

ECU

Originally posted by mzmtg


So your is on the ECU or the tranny? I was thinking of doing exactly that, putting a switch in at the ECU end of the thing.

[mtrai760]

Hmmm.... a free go faster mod... Thanks!...

Now the Mustangs won't pass me after I hit my limiter

[mzmtg]

After a little more study of wiring diagrams...

I think this will disable the cruise control on 97-99 models. This has to do with the way they integrated the circuitry for the instrument cluster in those years.

[Sprint™]

more reason to put a switch on that baby and use it at will... another note Ben... i know you did specify that the right hand side is where the blue wire is.. but on the left hand side is also a blue/pink wire.. make sure you get the idiots to know .. by telling them its near the two white wires and the black wire...

Originally posted by mzmtg
After a little more study of wiring diagrams...

I think this will disable the cruise control on 97-99 models. This has to do with the way they integrated the circuitry for the instrument cluster in those years.

[mzmtg]

Originally posted by SprintMax
more reason to put a switch on that baby and use it at will... another note Ben... i know you did specify that the right hand side is where the blue wire is.. but on the left hand side is also a blue/pink wire.. make sure you get the idiots to know .. by telling them its near the two white wires and the black wire...

I wasnt paying that close attention. There is only one PINK wire with a BLUE stripe on there. I went in a wrote it up a while after I did it. I'll look at it later, unless someone else wants to go make sure I got the side right...

[Sprint™]

no you are right.. its on the right side... i figure this out because when i read my manual and it said pink and blue wire.. my cousin was under the panel with the soildering iron and i said cut the pink/blue wire.. and he said which pink/blue wire.. and i said.. their is only one damn wire so cut it and stop arguing.. and he said.. no two.. and looked and yup.. one on the left and one on the right.. but you are accurate with the right side.. just that these guys might get over anxious see the left side and cut it.. and i forgot what that one does.. but cutting random wires on the ECU can't be all that good

Originally posted by mzmtg


I wasnt paying that close attention. There is only one PINK wire with a BLUE stripe on there. I went in a wrote it up a while after I did it. I'll look at it later, unless someone else wants to go make sure I got the side right...

[ejj]

Originally posted by SprintMax
no you are right.. its on the right side... i figure this out because when i read my manual and it said pink and blue wire.. my cousin was under the panel with the soildering iron and i said cut the pink/blue wire.. and he said which pink/blue wire.. and i said.. their is only one damn wire so cut it and stop arguing.. and he said.. no two.. and looked and yup.. one on the left and one on the right.. but you are accurate with the right side.. just that these guys might get over anxious see the left side and cut it.. and i forgot what that one does.. but cutting random wires on the ECU can't be all that good

Is one pink with a blue stripe and the other blue with a pink stripe I assume?

[Sonic]

Good job, dude.

[mzmtg]

Originally posted by ejj5875


Is one pink with a blue stripe and the other blue with a pink stripe I assume?

Honestly, I dont know. I just went right for the PINK with BLUE stripe.

Also, the cruise control still works on my car, I used it on the way to work this morning.

Another point, in the manual, and according to Mr. Martin, the ECU uses the speed signal for other purposes be sides cruise and speed limiting. I was just wondering if anyone knows exactly why the ECU needs to know the vehicle speed for air/fuel or load calculations?

[Sprint™]

usually the engine would need to know the RPM or the Speed to determine how much AIR and FUEL to mix.. but the ECU is getting signals from the 2 front O2 Sensors, the RPM signal and the Throttle Position Sensor.. so i don't see why the ECU would need the Speed sensor to mix air and fuel with all the info its already getting

Originally posted by mzmtg


Honestly, I dont know. I just went right for the PINK with BLUE stripe.

Also, the cruise control still works on my car, I used it on the way to work this morning.

Another point, in the manual, and according to Mr. Martin, the ECU uses the speed signal for other purposes be sides cruise and speed limiting. I was just wondering if anyone knows exactly why the ECU needs to know the vehicle speed for air/fuel or load calculations?

[Sprint™]

i don't know.. but one is on the left hand side of the screw and the other is on the right hand side of the screw..

you want the one onthe right hand side of the screw.. it should be near two white wires and a big black wire

Originally posted by ejj5875


Is one pink with a blue stripe and the other blue with a pink stripe I assume?

[ejj]

Originally posted by SprintMax
i don't know.. but one is on the left hand side of the screw and the other is on the right hand side of the screw..

you want the one onthe right hand side of the screw.. it should be near two white wires and a big black wire

Good enough. Thanks.

[mzmtg]

Originally posted by SprintMax
usually the engine would need to know the RPM or the Speed to determine how much AIR and FUEL to mix.. but the ECU is getting signals from the 2 front O2 Sensors, the RPM signal and the Throttle Position Sensor.. so i don't see why the ECU would need the Speed sensor to mix air and fuel with all the info its already getting

Dont forget the MAF and the IAT. I dont think vehicle speed would have anything to do with engine management. Surely for the tranny, though.

[Sprint™]

IAT? is that an Auto tranny thing? i don't have one of those

Originally posted by mzmtg


Dont forget the MAF and the IAT. I dont think vehicle speed would have anything to do with engine management. Surely for the tranny, though.

[CharlieT]

Gotta say great job well done
Luckily I got no speed limiter but I will try this on my friend MAx.
PS: I have passed 130 on my max already...Yeee Ha!!!

[mzmtg]

Originally posted by SprintMax
IAT? is that an Auto tranny thing? i don't have one of those

IAT = Intake Air Temp....you should have one

[Sprint™]

Originally posted by mzmtg


IAT = Intake Air Temp....you should have one