: Long cranking, poor start



Wilk
03-11-04, 03:20 PM
I have a '99 seville which requires long crank times to start. I replaced the fuel pressure regulater which made it slightly better. When I took the regulator off there was actually air pressure in the fuel line, so I looked and it appears that air is actually bleeding into the lines from injectors. Is it possible that the injectors could be allowing air into the fuel line from the cylinders under compression?

I have both CPS's on my bench ready to go in, even though I understand they are not as problematic as the 2000 and up models.

Wilk
03-11-04, 03:27 PM
By the way, this 99 seville has 100,000 miles on it.

formulacarracerjim
03-13-04, 09:06 PM
Whats the fuel psi on key up and then during crank? Also bring up RPM on IPC during lOOOONG crank and see if you are reading RPM. Altho a scan tool or spark checker would be better for ign testing.
Ther is NEVER a more pressure at the lower tip of the injecter than in the fuel rail. Air can"t go back up inside thru tip. Jim

Wilk
03-15-04, 04:08 PM
I will give those a try. I dont have a fuel pressure guage, I will need to get one, but that makes sense.

BeelzeBob
03-17-04, 05:44 PM
I will give those a try. I dont have a fuel pressure guage, I will need to get one, but that makes sense.

Fuel pressure gauges are easy and cheap to fab up. Find an old AC charging kit for R12 systems...the schraeder valve fitting on the end of the hose fits the shraeder valve fitting on the fuel line....find a scrap gauge of 60 to 100 PSI and you are in business.


I would definitely look at the fuel pressure when cranking. It should jump instantly to full pressure when you hit the key. If it comes up slowly then something else is suspect.... like the fuel pump, the pickup sock, fuel filter, etc...

BeelzeBob
03-17-04, 05:49 PM
I have a '99 seville which requires long crank times to start. I replaced the fuel pressure regulater which made it slightly better. When I took the regulator off there was actually air pressure in the fuel line, so I looked and it appears that air is actually bleeding into the lines from injectors. Is it possible that the injectors could be allowing air into the fuel line from the cylinders under compression?

I have both CPS's on my bench ready to go in, even though I understand they are not as problematic as the 2000 and up models.


Did you also loosen the fuel rail and lift up the rail so that the injectors clear the sockets to watch for a dripping injector?? If an injector drips during shutdown it can have the same effect of causing a rich mixture at crank as a leaking fuel pressure regulator.

One clue here is does the long crank take place all the time or just hot restarts or just cold starts....??? If it only takes place on hot starts, next time try holding the throttle wide open before you crank. Put the accelerator to the floor, hold it, then crank . Obviously release it when the engine starts.... By holding the throttle wide open during cranking the PCM will go into "clear flood" mode and shut off the injectors momentarily. If the engine starts fine this way it is a sign that you are probably dealing with a rich mixture due to a leaking injector or FPR. I know you replaced it...but....try pulling the vaccum line off the FPR while the engine is idling and watch the vacuum nipple on the FPR for several minutes while the engine is idling to see if any fuel leaks out.