Stalling/idling rough/reduced driveability w/ broken ECTS (Coolant Temp Sensor) wire?
05-26-2009 | 08:42 AM
#1
Stalling/idling rough/reduced driveability w/ broken ECTS (Coolant Temp Sensor) wire?
I've been having a very intermittent problem for a couple of weeks now: here is a post I made about the problem like 3 weeks ago:
Then, last tuesday a similar situation occurred. I have NOT CHANGED ANYTHING since 5/8/09 when it first did this - and it drove PERFECTLY FINE from 5/8/09 to 5/19/09, probably 1200-1500 miles. This time I was in a parking lot (large strip mall parking lot) so I was able to stop immediately and checked my fuel pressure, fuel pressure seems perfectly steady even while the car is idling roughly - FP steady at 39psi give or take 1psi. Car finally dies at idle while I'm stopped in the parking lot poking around under the hood. I try to restart and it cranks and cranks and finally restarts, runs a little rough for a minute and then goes back to normal and I drive it from 5/19/09 to today 5/26/09 with no problems. I cleaned my MAF last week, did not see any difference in anything.
I drove the car until until this morning on the way to work when the symptoms started again: bucking (seemed like misfiring under acceleration), rough idle/car wanting to stall when i press the clutch in or take it out of gear - luckily I made it to a side street before it died on me in the middle of morning rush hour traffic, drove around on the sidestreet for a couple minutes and things seemed to clear themselves up without the car ever actually stalling on me, but then out of curiosity I stopped on the side of the road and popped the hood, idle FP was fine, but I noticed my radiator fans were on. I have a digital engine coolant temperature gauge and my coolant temps were NOT up to the temp at which the fans come on. so I look and then notice that one of the two wires to my ECTS (engine coolant temp sensor) is completely broken. so this is why my radiator fans are on. I am able to fiddle with the wire and barely touch it to the remaining strand of wire on the sensor and the radiator fans shut off. the remaining strand of wire is so tiny though that there is no possibility of repairing that wire by splicing or reconnecting it.
At this time though that I'm fiddling with the ECTS wire, the idle *seems* to be OK no matter whether I disconnect the wire or have it connected. Out of curiosity I decide to shut off the car and see if I can restart it. Sure enough, the car will not re-start. It just cranks and cranks and cranks. I try this a few times over then next 20 or 30 minutes and finally get the car to cough back to life and then everything seems fine. Since I was 3 miles from home and 25 miles from work I decide to drive the car back home, car drives back home just fine (no symptoms) and I park it and it idles just fine. I shut the car off and try to restart it immediately, and again, no start. crank crank crank no start. So that brings me to now. I'm inside posting on the .org.
So has anyone ever experienced the ECTS being completely disconnected making the car not want to start OR making the car misfire and idle roughly and basically unable to drive? I'm wondering if this morning on the way to work the wire finally broke all the way and that's why the car is now very difficult to start. After I post this I'm going to go back outside and try to start the car again. Any ideas appreciated.
Driving home from work 5/8/2009 I'm slowing down on the freeway in 5th gear and everything is normal, I was taking a moderate speed exit ramp from one freeway to another. When I get on the gas again to start accelerating to entry speed on the freeway I'm getting on to, the car starts bucking and misfiring... I immediately let off the gas and push the clutch in, engine idles down fine. I let the clutch back out and try again and it's the same thing, car can't accelerate because the thing is bucking and misfiring and ****. I try the same scenario one more time, clutch in, car idles down fine, clutch out, can't accelerate, once the accelerator i depressed car bucks and misfires. I throw the hazards on and pull over. Car seems to be idling OK, but when I press the gas even a slight bit in neutral, car bucks and misfires. Then it finally dies at idle. I didn't notice anything weird going on with the wideband at this time, things seemed normal, slightly right to slightly lean of stoich, nothing to indicate a problem.
I crank it over to see if it will start up again and it cranks and cranks for probably a good 5 seconds (long long time, car usually fires right up) and finally starts up, behavior is as before, idles fine for a few seconds, symptoms return when i press gas, then car finally can't idle and ides. I crank it over again to see if i can get it re started again and this time it won't start, just cranks. I pop the hood and go see if I can see anything under the hood. My thoughts are that either I have a giant vacuum leak like my custom ghetto intake has had a coupler come off after the MAF, or that the fuel pickup on my walbro has fallen off again (I was fairly close to the end of a tank though I could have easily gotten another 40-50 miles).
Nothing seems amiss under the hood, all electrical connectors appear to be in place, fuel pressure is reading right about what it normally does after the car is just shut off (somewhere in the mid 20s). At this point I'm of course pissed because I hate this car now. about 3 minutes elapses probably, I get back in the car and decide to crank it over again. cranks over probably 5 seconds (long long crank again) but fires up, I give it gas and everything seems normal. gas it again and seems normal. I try to drive a little bit on the shoulder (i was coming up on a construction area and only had about 500' of shoulder left before I would be FORCED to get out into rush hour traffic on a major freeway that is already bottlenecked down from 5 lanes to 3 lanes from construction so I was DREADING getting back into a traffic lane and then having it die again). Everything seems OK so I chance it, I'm only .75 miles from my exit and I go for it and hope to god I can make it to my exit without it dying again. I make it to my exit just fine. I drive to the gas station (was going to get gas anyways since I was close to needing it anyways and I'm driving back home to michigan tomorrow for mother's day). I shut it down at the gas station without thinking, but it fires right back up as if nothing ever happened. Get gas and drive it home, car is operating now like there was never a problem at all.
Setup is:
NA VQ35, aeromotive AFPR, greddy emanage/walbro 255 (ghetto I know but I've NEVER had a problem with this installation and it's been in the car for 5 years now, never had to touch it once). I mean there's basically nothing to this thing, and NOTHING has been touched on it in over a year as far as engine management/fuel delivery/spark delivery/anything. Car has been running like a top and then this.
Anyone have any idea? I was REALLY hoping for something like a MAF coupler that fell off or a huge vac line that had come off the intake manifold or something, that's easy, but none of that was the case, and this problem miraculously cleared itself up.
I crank it over to see if it will start up again and it cranks and cranks for probably a good 5 seconds (long long time, car usually fires right up) and finally starts up, behavior is as before, idles fine for a few seconds, symptoms return when i press gas, then car finally can't idle and ides. I crank it over again to see if i can get it re started again and this time it won't start, just cranks. I pop the hood and go see if I can see anything under the hood. My thoughts are that either I have a giant vacuum leak like my custom ghetto intake has had a coupler come off after the MAF, or that the fuel pickup on my walbro has fallen off again (I was fairly close to the end of a tank though I could have easily gotten another 40-50 miles).
Nothing seems amiss under the hood, all electrical connectors appear to be in place, fuel pressure is reading right about what it normally does after the car is just shut off (somewhere in the mid 20s). At this point I'm of course pissed because I hate this car now. about 3 minutes elapses probably, I get back in the car and decide to crank it over again. cranks over probably 5 seconds (long long crank again) but fires up, I give it gas and everything seems normal. gas it again and seems normal. I try to drive a little bit on the shoulder (i was coming up on a construction area and only had about 500' of shoulder left before I would be FORCED to get out into rush hour traffic on a major freeway that is already bottlenecked down from 5 lanes to 3 lanes from construction so I was DREADING getting back into a traffic lane and then having it die again). Everything seems OK so I chance it, I'm only .75 miles from my exit and I go for it and hope to god I can make it to my exit without it dying again. I make it to my exit just fine. I drive to the gas station (was going to get gas anyways since I was close to needing it anyways and I'm driving back home to michigan tomorrow for mother's day). I shut it down at the gas station without thinking, but it fires right back up as if nothing ever happened. Get gas and drive it home, car is operating now like there was never a problem at all.
Setup is:
NA VQ35, aeromotive AFPR, greddy emanage/walbro 255 (ghetto I know but I've NEVER had a problem with this installation and it's been in the car for 5 years now, never had to touch it once). I mean there's basically nothing to this thing, and NOTHING has been touched on it in over a year as far as engine management/fuel delivery/spark delivery/anything. Car has been running like a top and then this.
Anyone have any idea? I was REALLY hoping for something like a MAF coupler that fell off or a huge vac line that had come off the intake manifold or something, that's easy, but none of that was the case, and this problem miraculously cleared itself up.
I drove the car until until this morning on the way to work when the symptoms started again: bucking (seemed like misfiring under acceleration), rough idle/car wanting to stall when i press the clutch in or take it out of gear - luckily I made it to a side street before it died on me in the middle of morning rush hour traffic, drove around on the sidestreet for a couple minutes and things seemed to clear themselves up without the car ever actually stalling on me, but then out of curiosity I stopped on the side of the road and popped the hood, idle FP was fine, but I noticed my radiator fans were on. I have a digital engine coolant temperature gauge and my coolant temps were NOT up to the temp at which the fans come on. so I look and then notice that one of the two wires to my ECTS (engine coolant temp sensor) is completely broken. so this is why my radiator fans are on. I am able to fiddle with the wire and barely touch it to the remaining strand of wire on the sensor and the radiator fans shut off. the remaining strand of wire is so tiny though that there is no possibility of repairing that wire by splicing or reconnecting it.
At this time though that I'm fiddling with the ECTS wire, the idle *seems* to be OK no matter whether I disconnect the wire or have it connected. Out of curiosity I decide to shut off the car and see if I can restart it. Sure enough, the car will not re-start. It just cranks and cranks and cranks. I try this a few times over then next 20 or 30 minutes and finally get the car to cough back to life and then everything seems fine. Since I was 3 miles from home and 25 miles from work I decide to drive the car back home, car drives back home just fine (no symptoms) and I park it and it idles just fine. I shut the car off and try to restart it immediately, and again, no start. crank crank crank no start. So that brings me to now. I'm inside posting on the .org.
So has anyone ever experienced the ECTS being completely disconnected making the car not want to start OR making the car misfire and idle roughly and basically unable to drive? I'm wondering if this morning on the way to work the wire finally broke all the way and that's why the car is now very difficult to start. After I post this I'm going to go back outside and try to start the car again. Any ideas appreciated.
05-26-2009 | 09:07 AM
#3
Replace the ECTS, its cheap and fix whatever wire your saying is broken. When mine was going bad it was very intermittent too. Sometimes I had to crank it so long I didnt think it was going to start at all. Other times it started fine. When the motor was cold it would be very hard to start and I would have to rev it up to keep it from dieing again, it would be very choppy and mis-firey like you described. Once warmed up the car ran normal/idled normal everything.
here's a video of when my car had an ECTS problem.
http://smg.photobucket.com/albums/v4...t=8de3f4bd.flv
here's a video of when my car had an ECTS problem.
http://smg.photobucket.com/albums/v4...t=8de3f4bd.flv
05-26-2009 | 09:24 AM
#4
Indeed, the first thing I would do is replace that pigtail for the ECTS. I've got a hacked up wiring harness here, PM me your name/addy and I can throw one in the mail for you (if I can find it).
For now I'd just bridge the gap with some wire. Odd that it wasn't showing to be very rich on the wideband.
If that doesn't fix the problem (which I imagine it would) next thing I would personally be looking at for long/hard starts are the CKPS'/CPS, if they've got any sort of debris on them they could easily cause some starting issues.
Any (relevant) codes?
For now I'd just bridge the gap with some wire. Odd that it wasn't showing to be very rich on the wideband.
If that doesn't fix the problem (which I imagine it would) next thing I would personally be looking at for long/hard starts are the CKPS'/CPS, if they've got any sort of debris on them they could easily cause some starting issues.
Any (relevant) codes?
05-26-2009 | 03:55 PM
#5
Right after I made this post I went outside and was able to rig something to bridge the gap in the pigtail harness, problems seems to be cured. I tried it like 10 times... when the coolant is hot (over about 175 degrees F) then the car won't start without the ECTS plugged in. Bridge the gap and it fires up right away, it was 10 for 10 on those attempts so I'd say that was the problem. Thanks for the help guys. pmorh I'll pm you about that harness.
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