Here'* the problem:

Sometimes, the Bonnie will not start. The fuel pump will run, it will crank, and there is pressure in the injector rail, but it will not start. This is happening with increasing frequency (the first time was, ironically, the day of the first MN Bonneville Club meet back in April), particularly when: the car was driven a relatively short distance, the car was turned off less than 60 minutes but more than 15 minutes ago, and it'* warm outside. Invariably, if the car is allowed to sit for an hour after the failed start attempt, it will start right up with no problems. It also sometimes spontaneously starts starting again after numerous successive failed attempts, with no apparent ill effects.

I suspect it is somehow fuel related: The last time I encountered the no-start condition, I pulled a spark plug and found it to be dry. However, the fuel appears to get as far as the rails in a state of high pressure. The SES indicator does not turn on.

My best guess is that the camshaft sensor is experiencing a heat-dependent malfunction. That, or vapor-lock.

Any ideas?

Thanks!

Jeff

Can you start the car by opening the throttle about 10%?

Nope, throttle position seems to have no impact.

Any codes. Sounds like a Crankshaft Position Sensor.

What'* your mileage?

My guess is the crank sensor due to deterioration from coolant dripping on it.

I was affraid of that.

Still, if the crank sensor is the problem, I wonder why the no-start condition is heat and time dependent?

Teuobk, I experienced this exact problem about a year ago. I talked to a local pontiac service manager, and he quickly said "most likely its the fuel pressure regulator, we see this often, they begin to leak causing a flooding and a real hard start". I figured I would give it a try. To my delight the part was less than $15 and only took me 10mins to install, its right under the engine cover. I never had the hard starting problem again, I bet your problem is also a faulty fuel pressure regulator.

For the price and ease of installation compared to the crank sensor, you may want to try the fuel pressure regulator first.

BTW, I also had the dreaded crank sensor failure on this car.. but the symtoms were different, the engine just shut down while I was driving (sometimes on the highway!), then start back up in a few minutes, it never caused me any hard starts. Again, the service manager here said, "probably the crank sensor, but we would have to put it on the computer". He was right again..

let us know how you make out... the fuel pressure regulater switch is almost easier than changing the air filter in the bonnie

have a look at the ICM and the coil packs too...

The CPS is a Hall effect transistor. There are 2 scenarios with these:

1) Your symptom of occasional fail to hot restart

2) Dies while driving. May or may not restart.


2) frequently but not always follows 1).


Again, any codes set? Should help to differentiate CPS & fuel pressure reg.