Buy a shop manual too…
Hmm… I replaced the TPS and like I thought it doesn’t start. I set it in the position its supposed to be. I bought the crank sensor but it won’t get in until the tenth. Still can’t find what the fuel pressure is supposed to be on this car.
For lack of a better phrase, you computer could have “learned” an F’ed up set of sensor values, so it may be off in both closed loop and in open loop operation. You could try resetting the computer by leaving the battery disconnected over night. When you reapply power to it the next morning, it will be back at the default open loop programming. Check any adjustments you might have done to any of the sensors if possible with the car off BEFORE you restart the car. Once you’ve done all you can to ensure it should be in reasonable tune, go ahead and fire it up, and then make any fine tune adjustments as needed.
I doubt it’s a fuel tank debris problem, because if the in tank filter gets clogged that easily during idle (when the engine needs the minimum flow of fuel), you would have noticed a fuel starvation problem long before with regular driving (when fuel demand can be much higher due to higher loading and higher RPM).
It could also be a fuel pump or pump relay that warms up and fails.
A fuel pressure gauge will tell the story.
Even if you don’t know what the pressure should be you can compare the pressure when it’s running OK to the pressure when it’s failing.
Well all my questions will be answered later today. Its the moment of truth. I’m going to replace the filter, check fuel pressure, which should be 40 psi at idle, and replacing the CAS. Thanks for all of your help guys, I really appreciate it. I’l tell you how it goes. If you don’t hear from me in a while, you know that I failed and drove my car off the IH10 bridge in rush hour traffic. lol.
You mention the car runs fine cold.I would look for a bad temperature sensor or thermostat not operating properly.
Does your check engine light come on when the key is turned to the first position, or has someone plucked the bulb out?
If you have no check engine light on or no codes, look for something that does not have a wire attached to it like the thermostat. Also, the computer will never tell on itself i.e. no check engine light or code.
As you have learned by disconnecting the crank angle sensor-it is apparently working.
Don’t rule out the fuel pump. The injectors have a prolonged duty cycle when cold ,and behave ok in summertime with low fuel pressure.Check fuel pressure at operating temp.
I forgot to ask if you have checked for water in the gas tank.Did you check if the fuel filter is good?
From your description of the trouble I suspect you may have a valve timing problem. I’m not sure if the engine uses timing belts or not.
eeeaooo–DO you think that this could be MY problem too? closed vs. open loop? If so, why wouldn’t VW have caught this?
Well I got the CAS, but of course I ordered the wrong one, I needed to order the CPS (camshaft position sensor), and that one is around 300 dollars, so I won’t have that kind of cash in hand until a few weeks.
The fuel pump gets adequate voltage and the fuel filter is brand new.
I have already tried leaving the battery disconnected, for two whole days at that. So the ECU had to have reset.
I’m going to get the fuel psi checked but the testers are expensive, so I’m going to rent one from Autozone for 150 bucks. Thats just a deposit, though, they give you your money back when you return it to them.
By the way, this car has a timing belt Cougar.
The plugs are all relatively new. and the coils must work properly, because while the car was running, I diconnected each of them one at a time, and immediately noticed a difference in the way the engine was running.
Thanks for all of your help so far guys.