Hard Starting and Crankshaft Sensor: A new lesson learned
#82
OK, guys... I think I'm on to something.
I was up in Chicago and paid a visit to our old family mechanic to see what he could come up with about it.
He looked through his database and suggested I check out these two things:
Fuel Pressure Regulator, and the "Start Signal Fuse," which could be loose or corroded causing an intermittent start condition.
But there was one other thing he mentioned, and I'm willing to bet a bit on this one.
The battery.
A few other people have mentioned it, but we always respond that it cranks strongly and feels good. However, the mechanic pulled out his Snap-On tester and ran it through some tests and the batter came up as bad, only holding a 75% charge. It still WORKS fine, but he explained that when you first turn that key on, not only are you turning the starter and firing the plugs, but also powering up the computer and everything attached to it. He then suggested that I get a battery somewhere else because he knew I could install it myself. (I mentioned that to eliminate any doubt that he was just trying to sell me a battery.)
Just as an experiment, I've been doing something differently: making sure the climate control, radio, and automatic lights are all turned OFF when i shut the car down, thus eliminating any additional electrical load while starting. Before starting the car, I turn the key to "run" but wait a few seconds -- giving the ECM time to "power up" and do its thing.
And you know what? It starts PERFECTLY when I do this.
Let's have a few other people try this and see what happens.
I was up in Chicago and paid a visit to our old family mechanic to see what he could come up with about it.
He looked through his database and suggested I check out these two things:
Fuel Pressure Regulator, and the "Start Signal Fuse," which could be loose or corroded causing an intermittent start condition.
But there was one other thing he mentioned, and I'm willing to bet a bit on this one.
The battery.
A few other people have mentioned it, but we always respond that it cranks strongly and feels good. However, the mechanic pulled out his Snap-On tester and ran it through some tests and the batter came up as bad, only holding a 75% charge. It still WORKS fine, but he explained that when you first turn that key on, not only are you turning the starter and firing the plugs, but also powering up the computer and everything attached to it. He then suggested that I get a battery somewhere else because he knew I could install it myself. (I mentioned that to eliminate any doubt that he was just trying to sell me a battery.)
Just as an experiment, I've been doing something differently: making sure the climate control, radio, and automatic lights are all turned OFF when i shut the car down, thus eliminating any additional electrical load while starting. Before starting the car, I turn the key to "run" but wait a few seconds -- giving the ECM time to "power up" and do its thing.
And you know what? It starts PERFECTLY when I do this.
Let's have a few other people try this and see what happens.
#84
Fuel pressure: I used to have an in dash electric FP gauge, even when the car was hard starting I had 51 psi FP.
Battery: I just had to replace my battery last week. Car started like a champ for a while, then went back to it's usual ways.
Turning off accessories: doesn't help in my case.
Letting the ECU "warm up" doesn't help either.
I still haven't straightened out my crank sensor wiring. The donor engine was from a totaled I35 that was smacked hard in the front, and the pass side CV carrier was shattered, which is nearby the crank sensor. Additionally, that oil line from the oil filter by the crank sensor was damaged in the wreck, which may indicate a faulty crank sensor in my case. Too darn lazy to look at it unless it dies completely.
Battery: I just had to replace my battery last week. Car started like a champ for a while, then went back to it's usual ways.
Turning off accessories: doesn't help in my case.
Letting the ECU "warm up" doesn't help either.
I still haven't straightened out my crank sensor wiring. The donor engine was from a totaled I35 that was smacked hard in the front, and the pass side CV carrier was shattered, which is nearby the crank sensor. Additionally, that oil line from the oil filter by the crank sensor was damaged in the wreck, which may indicate a faulty crank sensor in my case. Too darn lazy to look at it unless it dies completely.
#85
More likely it is your fuel pressure regulator which is bleeding off. when you turn on the ignition and wait, it gives fuel pressure time to build. Ask that mechanic to put the fuel pressure gauge on it and see if it is holding pressure when you turn off the car.
#87
Mine is likely Fed since the car was bought in IL, however I never really checked either way.
Now... here's an interesting new dimension which might add some wondering to the fuel system suspicions.
I noticed it was starting to act up again, then suddenly it got better. And then I realized that somewhere in the past few days I filled up my gas tank, it was low enough to set off the "feed me" light.
I think I'm going to go back and explore all the fuel-related suggestions thave have come up. I'm sure I've covered everything electrical.
Now... here's an interesting new dimension which might add some wondering to the fuel system suspicions.
I noticed it was starting to act up again, then suddenly it got better. And then I realized that somewhere in the past few days I filled up my gas tank, it was low enough to set off the "feed me" light.
I think I'm going to go back and explore all the fuel-related suggestions thave have come up. I'm sure I've covered everything electrical.
#88
i had my maxima for a bout five years and has been a problem since day one. i changed almost every thing
both cranksensor
camshaft sensor
condenser
maf sensor
all coils and put new plug
burned numerous starters out from cranking
have ran 4 guage ground wires to every thing
and still have starting problems
i have recent gotton an engine harness b/c i saw a bullitin that the wire breaks on the right fire wall
if there is sumtin else you think i missed let me know
both cranksensor
camshaft sensor
condenser
maf sensor
all coils and put new plug
burned numerous starters out from cranking
have ran 4 guage ground wires to every thing
and still have starting problems
i have recent gotton an engine harness b/c i saw a bullitin that the wire breaks on the right fire wall
if there is sumtin else you think i missed let me know
#89
I have been having this issue for a few months and have read this thread and MANY others trying to figure out the problem.
Today I went out and tryed to start my 2000 Maxima SE 215k miles, original starter, and it cranked very light but would not start. Got in my truck and left thinking about all the threads I have read, crank, cam & other sensors, ground wire, etc. Got back home and reread some of the the thread I had emailed to myself.
I took out the battery, disconnected the airbox just in case I needed to get to the starter motor. Ran down to Autozone & had the battery tested (only 1 year old bought from them) It tested 12.7, so that was good. I went back home and took out the starter. Great info here if you need to do this. http://www.cardomain.com/ride/207643...-nissan-maxima
I took it down and had it tested. Result = PASS I am now getting anxious, what could it be? Test again = PASS Somehow it just does not sound right. We test it five times and it passes every time, gear coming out but still does not sound strong. Test it a 6th time and FAIL.
He grabs a new starter and hooks it up & starts the test. From the moment it got power you could hear the difference by 100x!
Bought the new one and it cranks over very fast with no problems.
Hope this helps someone, if I have any issues I will check back in and let you all know.
Good luck!
Today I went out and tryed to start my 2000 Maxima SE 215k miles, original starter, and it cranked very light but would not start. Got in my truck and left thinking about all the threads I have read, crank, cam & other sensors, ground wire, etc. Got back home and reread some of the the thread I had emailed to myself.
I took out the battery, disconnected the airbox just in case I needed to get to the starter motor. Ran down to Autozone & had the battery tested (only 1 year old bought from them) It tested 12.7, so that was good. I went back home and took out the starter. Great info here if you need to do this. http://www.cardomain.com/ride/207643...-nissan-maxima
I took it down and had it tested. Result = PASS I am now getting anxious, what could it be? Test again = PASS Somehow it just does not sound right. We test it five times and it passes every time, gear coming out but still does not sound strong. Test it a 6th time and FAIL.
He grabs a new starter and hooks it up & starts the test. From the moment it got power you could hear the difference by 100x!
Bought the new one and it cranks over very fast with no problems.
Hope this helps someone, if I have any issues I will check back in and let you all know.
Good luck!
#91
Looking your help with 2001 20th AE cranks but not start? I've taken out the two crank and the cam sensor cleaned and ohm to specs. Let me give a time line of the past week. State was defective and so I changed it, I also cleaned carbon out of the intake and an oil change. I drove it for a couple days and all seemed ok. I drove to work with no problems and when I was leaving it just cranked with no start. I have no tried to check for codes. I'll try today. It has a full tank of fuel. I did add some fuel system cleaner - Chevron Techron Fuel System Cleaner, 20 oz. it just cranks and cranks... no turn over at all..
#92
@Montego Murph - wondering if you've made any progress with this. I've got very similar starting problems along with a SES. Took it to my mechanic, it's showing P0300, P0140, P0420. Autozone confirms P0300 and P0140. Not sure if they're related to my starting problem though...
#93
Well people, I think I nailed it.
The in-tank fuel filter.
I took the pump assembly apart to attack a different issue and accidentally found out the filter was pretty dirty -- when I tipped it over, muddy gas poured out. I cleaned it as best I could (wasn't able to get a replacement at that hour) and reassembled everything, and it's been 90% flawless. It's gotta be related somehow.
I still want to look into the fuel pressure regulator though for that extra 10%
The in-tank fuel filter.
I took the pump assembly apart to attack a different issue and accidentally found out the filter was pretty dirty -- when I tipped it over, muddy gas poured out. I cleaned it as best I could (wasn't able to get a replacement at that hour) and reassembled everything, and it's been 90% flawless. It's gotta be related somehow.
I still want to look into the fuel pressure regulator though for that extra 10%
Last edited by Montego Murph; 12-27-2011 at 05:07 AM.
#95
@Montego Murph - wondering if you've made any progress with this. I've got very similar starting problems along with a SES. Took it to my mechanic, it's showing P0300, P0140, P0420. Autozone confirms P0300 and P0140. Not sure if they're related to my starting problem though...
After getting the above codes pulled, i just didn't want to spend so much time determining exactly what it was, so I ended up taking it to the dealer. They confirmed many of the same codes already found but also specifically said they found a bad injector. All together, they wanted $1800 to fix the injector, 2 os sensors, and all the coils. I wasn't about to do it all, as I figured some were related to the root issue. So I asked what the minimum/first thing we could do would be and they suggested the injector. They replaced that, along with the plug, reset the codes, and it has been starting and running perfectly since.
So in my case, a bad injector was the root cause of hesitant start + rough idle, resulting in the codes P0300, P0140, and P0420. Maybe that'll help somebody!
#96
Wow I just read three pages of threads and for my 01 Maxima that has a hard time starting after it warms up. No one has a clue on what to do. I changed both crank sensors, maybe I try the cam sensor next. I'm lost don't no what to do.
#97
I changed one crankshaft sensor (near oil filter) and camshaft sensor. No change in my inconsistent hard starting.
Last weekend I changed out the other crankshaft sensor behind the tranny and my fuel strainer. I had a hard start the morning after, but not too bad. It has started up fine since.
If it starts hard again I'm going to change out the ignition switch and relay. If that doesn't work I'll pull the starter and have it tested and replaced if needed.
Mine doesn't seem like a fuel delivery problem because it runs perfectly fine after I get it started...no hesitation, no stalling.
Last weekend I changed out the other crankshaft sensor behind the tranny and my fuel strainer. I had a hard start the morning after, but not too bad. It has started up fine since.
If it starts hard again I'm going to change out the ignition switch and relay. If that doesn't work I'll pull the starter and have it tested and replaced if needed.
Mine doesn't seem like a fuel delivery problem because it runs perfectly fine after I get it started...no hesitation, no stalling.
#98
Keep me posted on what happens over the next week or two. I noticed that after I messed with the crank/cam sensors it would start fine for a few days and then go back to its old self.
#99
Yeah...I will. I fear mine will do the same. I do have a bit of an oil leak which leaves some residue on the crank sensors which may be a factor. If I find it hard starting I'll check there first and clean them to see if there is a difference.
#100
try this fellas, I had somewhat of the same issue, mine was a little different but this made a huge world of difference, so it would be worth a shot before any more money is thrown at it.
Hard Starting Issue
Hard Starting Issue
#102
I had this issue, did all above, turns out, Bad ground, ran 2 gauge from a nice CLEAN bolt on the transmission to the Negative on the battery, Been almost 2 years, fires off instantly every time. i have a thread around, check it out, has vids also.
#103
Still have the problem after changing both crank sensors, camshaft sensor, and fuel strainer. I'll try the 2 gauge wire for the ground and see how that goes.
I'm still going to order the ignition switch and change it out anyhow.
If the ground and the ignition switch don't fix it, all that is left is the starter...
I'm still going to order the ignition switch and change it out anyhow.
If the ground and the ignition switch don't fix it, all that is left is the starter...
#104
It looks like the ground wire worked for me. I can't say for the long-term as I only started it 5 times with the ground wire installed.
I can say I did notice a difference right off the bat with an immediate start last night. The dash lights look a little brighter too, but it may just be a placebo affect.
The best indicator was this morning when the Max usually struggles to start. This time it started up as normal, almost as if new.
Since I ordered the ignition switch I'll change it anyhow. Looks like I should get another 100,000 miles out of this Max, no problem!
Thanks Prof! Wish I saw your thread sooner.
I can say I did notice a difference right off the bat with an immediate start last night. The dash lights look a little brighter too, but it may just be a placebo affect.
The best indicator was this morning when the Max usually struggles to start. This time it started up as normal, almost as if new.
Since I ordered the ignition switch I'll change it anyhow. Looks like I should get another 100,000 miles out of this Max, no problem!
Thanks Prof! Wish I saw your thread sooner.
#105
unplug crank sensor car starts
Starts with crank sensor unplugged after cycleing 5-6 time and not turning key to OFF position
02 Maxima, auction car, determined engine was swapped verified by Nissan. dealer said they could not tell, that was BS Nissan said. Nissan could tell me the serial number for original engine but could not cross the donor engine number to tell me what year , generation etc, must be quite limited database.
org egn # vq35 246440, donor vq35 22148A if that means anything to anybody
New crank sensor installed for an "02" (who knows what year)question are there two connectors set up for crank sensor by radiator or they splice in a different one to try, heat seal tape on it
Went to dealer to re flash ECM and key reprogrammed, head mechanic said no it would start if key wasn't already programmed to EMC (I have to believe that was swapped too, just laying on the hump behind console)
CEL on, had NATS Codes, crank and cam sensor code, p0725 speed sensor, so agree to let him put on the machine.
Guess what, could not clear NATS code w/o reprogramming key, then cleared. Still had Crank CAM, Engine speed sensor code, did some continuity tests and gave up, said used parts, wire splices, different engine and ECM.
Only charge me $50 bucks.
I would replace cam sensors but afraid of not being a 5th gen engine.
any ideas?
02 Maxima, auction car, determined engine was swapped verified by Nissan. dealer said they could not tell, that was BS Nissan said. Nissan could tell me the serial number for original engine but could not cross the donor engine number to tell me what year , generation etc, must be quite limited database.
org egn # vq35 246440, donor vq35 22148A if that means anything to anybody
New crank sensor installed for an "02" (who knows what year)question are there two connectors set up for crank sensor by radiator or they splice in a different one to try, heat seal tape on it
Went to dealer to re flash ECM and key reprogrammed, head mechanic said no it would start if key wasn't already programmed to EMC (I have to believe that was swapped too, just laying on the hump behind console)
CEL on, had NATS Codes, crank and cam sensor code, p0725 speed sensor, so agree to let him put on the machine.
Guess what, could not clear NATS code w/o reprogramming key, then cleared. Still had Crank CAM, Engine speed sensor code, did some continuity tests and gave up, said used parts, wire splices, different engine and ECM.
Only charge me $50 bucks.
I would replace cam sensors but afraid of not being a 5th gen engine.
any ideas?
Last edited by spete239; 03-27-2012 at 01:56 PM.
#106
Starts with crank sensor unplugged after cycleing 5-6 time and not turning key to OFF position
02 Maxima, auction car, determined engine was swapped verified by Nissan. dealer said they could not tell, that was BS Nissan said. Nissan could tell me the serial number for original engine but could not cross the donor engine number to tell me what year , generation etc, must be quite limited database.
org egn # vq35 246440, donor vq35 22148A if that means anything to anybody
New crank sensor installed for an "02" (who knows what year)question are there two connectors set up for crank sensor by radiator or they splice in a different one to try, heat seal tape on it
Went to dealer to re flash ECM and key reprogrammed, head mechanic said no it would start if key wasn't already programmed to EMC (I have to believe that was swapped too, just laying on the hump behind console)
CEL on, had NATS Codes, crank and cam sensor code, p0725 speed sensor, so agree to let him put on the machine.
Guess what, could not clear NATS code w/o reprogramming key, then cleared. Still had Crank CAM, Engine speed sensor code, did some continuity tests and gave up, said used parts, wire splices, different engine and ECM.
Only charge me $50 bucks.
I would replace crank sensors but afraid of not being a 5th gen engine.
any ideas?
02 Maxima, auction car, determined engine was swapped verified by Nissan. dealer said they could not tell, that was BS Nissan said. Nissan could tell me the serial number for original engine but could not cross the donor engine number to tell me what year , generation etc, must be quite limited database.
org egn # vq35 246440, donor vq35 22148A if that means anything to anybody
New crank sensor installed for an "02" (who knows what year)question are there two connectors set up for crank sensor by radiator or they splice in a different one to try, heat seal tape on it
Went to dealer to re flash ECM and key reprogrammed, head mechanic said no it would start if key wasn't already programmed to EMC (I have to believe that was swapped too, just laying on the hump behind console)
CEL on, had NATS Codes, crank and cam sensor code, p0725 speed sensor, so agree to let him put on the machine.
Guess what, could not clear NATS code w/o reprogramming key, then cleared. Still had Crank CAM, Engine speed sensor code, did some continuity tests and gave up, said used parts, wire splices, different engine and ECM.
Only charge me $50 bucks.
I would replace crank sensors but afraid of not being a 5th gen engine.
any ideas?
#109
If it runs then I can guarantee you that you have a 5.5 gen engine (2002/2003). They are exactly the same. You should be able to use a crank sensor as a direct replacement and be sure it is the right part.
I'd start with replacing the crank sensor. Make sure you go OEM as aftermarket replacement sensors are sketchy.
I'd start with replacing the crank sensor. Make sure you go OEM as aftermarket replacement sensors are sketchy.
#111
BTW I took out crank sensor to bring with me, this is a new one the guy tried. but gave info for an 2002 # A29662-L33, looking at Nissan parts site looks like they go to 02, then 03 to present so 5.5 generation would probably be 03.
#112
5.5 gen applies to both 2k2 and 2k3. For that part, there is a split by the VIN which may present a sticky situation for you. It is good you brought the part with you so they could match it up exactly...hopefully. Was the parts guy able to find an exact match based on the part you brought in?
#113
2nd Dealer not much help, said number on crank sensor are manufacturer number, suggested nissan motorsport site might be able to get engine vin # info.
being a newbe( Dealer never heard of generation terms). If the donor engine was from a M/T and they changed flywheel is there a shim needed or are there 2 type of A/T trannys that need to shimmed? I dont have car home, my concern is the alignment of signal plate, should be perfectly aligned in center of CKP hole and/or could it be installed 180 degrees off? . but it does run and pretty good.
being a newbe( Dealer never heard of generation terms). If the donor engine was from a M/T and they changed flywheel is there a shim needed or are there 2 type of A/T trannys that need to shimmed? I dont have car home, my concern is the alignment of signal plate, should be perfectly aligned in center of CKP hole and/or could it be installed 180 degrees off? . but it does run and pretty good.
#114
2nd Dealer not much help, said number on crank sensor are manufacturer number, suggested nissan motorsport site might be able to get engine vin # info.
being a newbe( Dealer never heard of generation terms). If the donor engine was from a M/T and they changed flywheel is there a shim needed or are there 2 type of A/T trannys that need to shimmed? I dont have car home, my concern is the alignment of signal plate, should be perfectly aligned in center of CKP hole and/or could it be installed 180 degrees off? . but it does run and pretty good.
being a newbe( Dealer never heard of generation terms). If the donor engine was from a M/T and they changed flywheel is there a shim needed or are there 2 type of A/T trannys that need to shimmed? I dont have car home, my concern is the alignment of signal plate, should be perfectly aligned in center of CKP hole and/or could it be installed 180 degrees off? . but it does run and pretty good.
I know it sucks, but you may have to buy both CPK sensors and see which one works.
#115
#116
Signal plate look dead center of sensor opening and when cranking over runs true, what I notice is where the Bell housing and engine meet to create the sensor opening they are not flush, engine is 1/4 in higher so thats as far as the sensor will go. Using a caliber I determined from the sensor to the high spot of the signal plate is 1/4 inch, is that to much clearance for the sensor to pick up?
#117
Sorry I don't have pics to post. I have a 2k auto tranny and there is an open thread on the top of the tranny almost directly under the ABS actuator. If I recall it is a size 10M x 1.25 threading. It is relatively shallow, around a 1/2 inch or less in depth. The other connection point in the negative battery terminal. Total length of cable was 2.5 feet.
#118
Signal plate look dead center of sensor opening and when cranking over runs true, what I notice is where the Bell housing and engine meet to create the sensor opening they are not flush, engine is 1/4 in higher so thats as far as the sensor will go. Using a caliber I determined from the sensor to the high spot of the signal plate is 1/4 inch, is that to much clearance for the sensor to pick up?
#119
To test ck crank sensor u need a scope, no ohms or test with a screw driver sensor hooked up and pass a screwdriver pass it and get voltage reading, I will do that I think it either 5 or 12 v. I should also see how close the signal ring clearance is. 1/4 in might be enough or need longer sensor, or start grinding
#120
To test ck crank sensor u need a scope, no ohms or test with a screw driver sensor hooked up and pass a screwdriver pass it and get voltage reading, I will do that I think it either 5 or 12 v. I should also see how close the signal ring clearance is. 1/4 in might be enough or need longer sensor, or start grinding
http://boredmder.com/FSMs/Nissan/Maxima/2002/
It is under the "EC" or Engine Control. Download it and do a search on "crankshaft" and you will see the specific testing procedures, how the sensors should be installed, etc.