1998 Trans Am cutting out - Can't figure it out
12-15-2012, 05:15 PM
#1
1998 Trans Am cutting out - Can't figure it out This is the first time in a very long time that I've been stumped on an issue, but I can't figure this one out. The car is a bone stock 1998 Trans Am A4. Usually when idling, it idles smooth then the engine will just cut out like you shut the key off. It is the engine only though, no lights, power accessories, etc cut out. Sometime it will completely die and other times it will catch itself and come back. It will also do it going down the road at steady speed randomly, but never completely dies at steady speed. This has been going on for two days.
Today, there was 3 times that it would not start. Holding the pedal to the floor (putting the PCM in flood mode) would get it to start, but not every time. Regardless, it does not seem like it would have started without doing this.
The car has newer plugs and wires, everything is in good mechanical order. I verified fuel pressure and there is no question that it is not a fuel pump issue. There is also no check engine light and no stored codes.
Like I said, the issue is isolated to the engine cutting out. It is definitely not a main power/ground issue. When it does it, there isn't really any sputtering. It's more like an on/off type of cutting out.
I don't have a Tech 2 and I don't know where to go from here. Anyone got any ideas?
Today, there was 3 times that it would not start. Holding the pedal to the floor (putting the PCM in flood mode) would get it to start, but not every time. Regardless, it does not seem like it would have started without doing this.
The car has newer plugs and wires, everything is in good mechanical order. I verified fuel pressure and there is no question that it is not a fuel pump issue. There is also no check engine light and no stored codes.
Like I said, the issue is isolated to the engine cutting out. It is definitely not a main power/ground issue. When it does it, there isn't really any sputtering. It's more like an on/off type of cutting out.
I don't have a Tech 2 and I don't know where to go from here. Anyone got any ideas?
12-15-2012, 05:23 PM
#2
The crank sensor sometimes does that.
If the crank sensor stops sending signal the engine dies and won't start. The issue will come and go and will be worse with time
I can't be sure this is your problem but a sensor is cheap and easy to change, maybe it's worth a try
Aren't you getting any DTC's?
If the crank sensor stops sending signal the engine dies and won't start. The issue will come and go and will be worse with time
I can't be sure this is your problem but a sensor is cheap and easy to change, maybe it's worth a try
Aren't you getting any DTC's?
12-15-2012, 05:30 PM
#3
I am getting a P0118 and the temp gauge hasn't been working. I didn't mention it in my first post because I figured it was unrelated, but now I am doing some research and seeing that it could be related. I have a spare of about every sensor there is. I am going to look more into the P0118
12-15-2012, 07:02 PM
#4
Well I got it fixed. Turned out to be the pins in the coolant temp sensor pigtail. They were just loose and making intermittent contact with the pins in the sensor. Fixed and pins and problem solved.
Unplugged it with the car running to verify, and it does in fact cut out and not start well, etc without the coolant temp sensor.
Went on a 20 mile drive and not a hickup or SES light.
Unplugged it with the car running to verify, and it does in fact cut out and not start well, etc without the coolant temp sensor.
Went on a 20 mile drive and not a hickup or SES light.
12-16-2012, 12:32 PM
#5
yes I have seen that. with ect sensor unplugged the pcm reads -38 degrees and it causes a super rich condition, engine barely starts and runs roughthats why checking for dtcs is a must
