so i thought.... the problem is back

I think its time to upgrade to a c5 or a c6. I cant keep up with it, time to sell I think!

 

My engine is acting much the same as your engine. Reading this forum has led me to believe it is either a leaking injector or a bad fuel sending unit (includes the pump, fuel lines, fuel level float, and a few other parts) So i put a fuel pressure gauge on it before i started to buy parts. I would encourage you to do this if you have not already. As soon as you turn the ignition on you will either notice the gauge move or not. For me, i saw the gauge go to about 30 pounds which is 10 below where it should be. I then got the car to start and it coughed and sputtered and started hard, but once going runs well. The pressure stabilized at 40 pounds. Shutting the car off i watched the gauge drop to 30 pounds in one minute, 20 pounds in 3 minutes, and then to 10 pounds in 10 minutes. This is way too fast for pressure to go down. I ohmed the injectors and they all check OK. I have ordered a new fuel sending unit and will install this weekend and see if that cures the hard cold starting issue.

My theory is that with a tank that is down to the last quarter tank, a bad fuel pump check valve allows the pressure to drain back to zero, and may even allow air to back feed to the injector rails. When the pump comes on first thing in the morning, it not only needs to pressurize the rails, but it needs to expel air too. Others may know this much better than i do, but that is what i think may be happening to my car. I will try to remember to report back after the install.

steve

 

Get it pumped up then clamp off the rubber hose from the tank if it holds it is you check valve in your pump or a bad hose or tube in your tank

 

Well, after letting her sit a while and doing some other things, I am back on this again.

Drove her to work today. Nice hard start like before (injector replacement did nothing).

Things I am noticing:

*I can smell gas in the car faintly.
*Not getting good mileage
*Sputtering a little (It wasnt before till the timing got adjusted, going to get that adjusted again to normal)

What else can this be? Pressure regulator? It ran perfect before the first hard start.... The injectors werent the cause (even tho shop said they were....)

Any ideas guys?

 

Pull the vacumme line off the fpr and smell for gas. Did you ever pump it up and clamp the fuel line off?