johnwsc
Dec 26th, 06, 06:37 PM
i have a 1990 305 tpi that takes atleast 10-15 seconds of cranking to start only if the car sits over night.if you have it running it will restart very well.the car only has 25,000 miles so i would expect it to be something minor. any help would be appreciated.
john
Everett#2390
Dec 27th, 06, 07:15 AM
During the first cold start, turn ign key to IGN and listen for the "whirl/buzz" of the fuel pump in the tank. The ECM turns on the fuel pump for 2-3 seconds via the fuel pump relay located by the driver hood hinge.
An alternate path for fuel pump power is through the oil sending unit. Oil pressure is made, switch contacts close, pump pumps. Of course, takes time to build oil pressure with cold oil.
Everett#2390
Dec 27th, 06, 03:12 PM
You're welcome. Let us know what happens either way.
johnwsc
Dec 28th, 06, 07:17 PM
everett,
i checked the fuel pump it comes on for aprox 2-3 seconds until the relay trips it.any other ideas?
thanx,
jw
Everett#2390
Dec 29th, 06, 07:16 AM
Okay, apparently control for the fuel pump relay is good.
Look on the driver side of intake between Cyl's 3 & 5 for a cold start injector. I know 85 TPI has them.
When the engine starts, does it run smoothly from the first ignition or runs alittle ragged?
If you have a fuel pressure gauge to measure the quickness of pressure build-up and amount of pressure, I'd turn the key on & off s few times to allow the pump tobuild pressure and see if cranking time shortens.
Rocvert
Dec 29th, 06, 09:24 AM
I believe the 90 Iroc would NOT have the cold start injector
I think 89-92 camaro's had Speed denisty system vs. MAF
and no cold start injector.
Musclerodz
Dec 30th, 06, 10:58 PM
Check the oil pressure saftey switch. there is one for the guage and a saftey switch to keep from starting the engine dry
Mike