88 and 89 951 starting and running problem
12-12-2002, 06:07 PM
#1
Race Car
Thread Starter
88 and 89 951 starting and running problem
I have a 1988 951 my fiance drives and started with the car cutting out at any speed and throttle position intermittently even at idle. It did not happen often in the beginning and it got worse. It eventaully started to stall the car and I had to restart. Now at times it won't even start. It did not seen like a fuel problem because it did not only do that under heavy load. I let the car sit for about a week and changed it out with my 1986 dme and klr and it started even though it ran kinda funny. I thought the computer was bad until I drove the car about 10 miles and it started to cut out again. It is driving me crazy. At the same time, my 89 turbo refused to start. When it does not want to start, it won't start no matter how much the engine cranked. When the car starts, it runs without any problems and it does not cut out or stall. It either starts and runs well or it won't start and run at all. The car has a slow drain and will kill the battery in about 4 days of sitting and has a factory alarm. I am not sure whether the alarm is causing this to happen. Please help and give me some hints as far as what could cause these problems. I have many spare parts I can swap out but never ran into these problems before....Thanks for any advice you guys can give me.
12-12-2002, 09:01 PM
#2
Three Wheelin'
Legoland:
First check the ground straps on top of the bellhousing and rear of engine block.
Next check the connectors for the speed and reference sensors. They get brittle and can become intermittent. Look on the rear of the intake manifold. They are connected in a bracket that bolts to the manifold. Two rectangular and one round. The rectangles are the speed/ref. The round is the O2 sensor.
Next, check the throttle position sensor. This is both a switch and a potentiometer. I can give you some specs and pin locations if you need them.
Next, check the engine temp sensor.
Next...Uh, I forgot the next step in the troubleshooting sequence.
You can check the fuel pressure and delivery, but you need a gauge and metric adapter to connect to the fuel rail.
First check the ground straps on top of the bellhousing and rear of engine block.
Next check the connectors for the speed and reference sensors. They get brittle and can become intermittent. Look on the rear of the intake manifold. They are connected in a bracket that bolts to the manifold. Two rectangular and one round. The rectangles are the speed/ref. The round is the O2 sensor.
Next, check the throttle position sensor. This is both a switch and a potentiometer. I can give you some specs and pin locations if you need them.
Next, check the engine temp sensor.
Next...Uh, I forgot the next step in the troubleshooting sequence.
You can check the fuel pressure and delivery, but you need a gauge and metric adapter to connect to the fuel rail.
