can anyone help with cold start system issues on a 93 lt1 equiped car, trying to help a freind out with his c4

 

Can you give us a few more details? Long cranking times? Won't stay running when cold? Runs rough? Throw us a bone here.

 

I threw out some details last week and got no response so I thought maybe vague was the was to go, anyway extended crank, usually six or so times before it will finally start, may die may not, once the engine is warmed up it will start with no issues for the rest of the day, any info on troubleshooting woudl be appreciated.

 

extended crank can idicate a fuel delivery issue. do a complete fuel pressure check and take out the IAC and clean it. Make sure you are receiving adequate spark.

Come back and let us know what you find.

 

Long cranking times are usually the result of a dead fuel pump relay. GM engineered a "backup plan" to start the car in the event of relay failure.....the oil pressure switch.

If the relay fails, the OP switch will close once approx. 4 psi of oil pressure builds during cranking, thus completing the circuit to the fuel pump and allowing the car to start. NOTE: The OP switch is wired in parallel....not series. It will NOT shut off the fuel pump to prevent engine seizure if oil pressure falls off to zero....so long as the fuel pump relay is operational, the pump will continue to run even if oil pressure falls off completely...it is not a failsafe.

The relay makes sense in your case. When the engine has been run, it will build oil pressure rapidly....when it sits overnight the oil drains back to the pan.

When you turn the key on, do you hear the pump run for the 2 second prime? Better yet, throw a fuel pressure gauge on the schrader valve and turn the key on. Does it build fuel pressure immediately? If not, crank the engine.....is there a few seconds of delay before pressure builds? If so, test the fuel pump relay. I think you're a $10 part away from the cure.

 

You beat me Sarge....I must be getting slow in my old age.

 

You were much more thorough. And I did forget to ask him if the pump was running!

I started to tell him you would give your 3 things it takes to run a car but just in case you were cleaning the doghouse, to get ready for company, I wouldn't commit you.

 

Your new avi...................just saying

 

Funny Kittah....funny. I've been down with the flu for 2 days now....I FEEL like the pic....just without the geriatric smirk.

I need to petition the mods to make my "They need 3 things to run" mantra a sticky. Would save me untold typing.

 

Well "I hope you get to feelin' better soon there hoss" (said in my best Texas accent) I will try to take up the slack while you're on the mend.
Tell the Mrs. to keep the chicken soup a comin"

 

Thanks my fine furry feline friend (this is getting out of hand ) The worst of it was yesterday....I actually came home from work and slept the whole afternoon. But the sympathy points from Ms Friz are a bonus.

It sucks though...I have a ton of stuff I'm just itching to do on Marco and I don't feel like doing anything. So here I am online, troubleshooting all across the fruited plain.

 

good information, this car belongs to a freind so when i get the chance i will get over there and check it out, i appreciate the input. will get back with the results