From a Hot Hard Start to a Hot No Run

[jeffnhiscars]

I don't drive my cabrio much these days but about a year ago, after visiting friends, it was hesitant to start. Tried a couple of times then it fired and got me home. More recently, running errands short enough to get it hot, same hard start problem although after a try or 2 it would start.

Last time out it actually died on the way home. Sat there for a minute then started it and drove home.

Running diagnostics in the driveway it would cold start fine the. At OT it would die, even at idle. Give it a rest and it starts.

I've installed a new CTS, NGKs and new FPR, injectors are recent refurbs swapped the coil, main relay & ohmed the CPS. AFM is a fresh Bavrest rebuild, cap and rotor are clean.

Bentley calls a hot hard start to be fuel related so I'm down to fuel pumps failing when hot but haven't rigged up my fuel pressure gauge yet. Just thought I'd put this out there since swapping pumps is not my favorite sport.

[jeffnhiscars]

I'm now getting a hard cold start and a 1223 CEL which is a CTS. Since I installed a brand new one it may just be a wire. It's just gets more and more interesting by the day

[ForcedFirebird]

For giggles, ohm your CPS when hot. I have had them go out of range based on temperature.

[jeffnhiscars]

For giggles, ohm your CPS when hot. I have had them go out of range based on temperature.

If I can get it to start again, I'll do that. Otherwise I'll take a run at the fuel pumps, do my over due timing belt, probably just swap the CPS WIIT, then pick up where I left off.

Maybe the belt jumped a tooth and this will all go away :-)

[ForcedFirebird]

Unfortunately timing belts don't typically jump a tooth, they will loose a couple cogs and eat themselves. :(

[jeffnhiscars]

Unfortunately timing belts don't typically jump a tooth, they will loose a couple cogs and eat themselves. :(

I'm not expecting a TB problem...just thinking that a segue to the belt update may uncover something related to the starting challenge.

I still think it's a fuel pump but we'll see.

[RobDog]

Try starting the car with the coolant temp sensor unplugged. If the car starts hold the throttle till the car can idle, than run and plug the CTS in or have a second person that can plug up the sensor for you. If the car starts with the sensor unplugged, than your car is having fuel related issues and probably running too rich.

[jeffnhiscars]

The CEL I was getting was fort the CTS which was new. Turns out I didnt have it pluigged in fully so thats fixed.

Finally got my fuel pressure guage sorted. Cold started fine with pressure about 33-35psi at idle which seemed a bit low given that I have a brand new FPR. With the vacuum hose off it rose to 38.

I just kept watching since the problem was when hot and after about 10 minutes the fuel pressure starting to drop then the engine died....SOOO...we need a new fuel pump :-)

[jeffnhiscars]

Installed a brand new Bosch FP & filter and its still dying from loss of fuel pressure at OT. Since the CTS and FPR are also brand new the only thing left I can think of is the ecu.

Interesting that my fuel pressure gauge still only read mid 30s

[jeffnhiscars]

Its a fine line between total exasperation and the need/desire to dig just a little deeper cause you know your getting closer. Alcohol helps

I decided that the moment it died I would remove the FP relay and jump it. However, having 2 other cars here I just borrowed a relay and popped that in when it died. Started right up, ran for 20 minutes, which it hasnt done in months, then went for a drive.

I do believe my Baby is back....all for a fuel pump relay..I hope :-)