intermitant nonstart

[christer130]

I have a 1986 corvette that has some starting problems. After two or three starts in a row the engine will crank and will not fire. It seems that I am not getting fuel and this will not happen every start, I could go for a few days without trouble, and is only when starting. Hoping you corvette experts could help out a new owner.

 

[jenavet]

hey
i wouldnt think it would be a fuel problem...either a fuel pump works or it dosent,usually not an intermitent problem...i had the same thing happen on one of my early vets and it turned out to be a bad ignition module....but it could be something different......when the problem is occuring someone is going to have to check for both spark and fuel...i had a real ghetto vet back in the day and i learned alot about them and how to fix them ,along the side of the road!!!

 

[JonM]

Check the wires on the starter...they are right next to the exaust and get brittle and corroded with time.

 

[Edmond]

Do what Jon said! If the wires look fine; pop the starter off, it's only 2 bolts, and bring it to a local auto store to get tested.

I was in the same situation last year; the car occassionally wouldn't start but would start fine other times. It was the starter. But check the wires and connections first because that's the first step.

 

[taegdh]

He said it would crank but not fire, my guess is that the fuel system is loosing pressure at the rails, due to a couple of things.

1. Dirty Injectors allowing fuel to leak down and into the head on top of the valve, where it eventually evaporates.

2. Bad fuel pressure regulator. Leakdown! via evaporative cannister.

3. Bad fuel filter. not enough volume in the fuel rail when it is shut down and the pressure then "equalizes", with the atmosphere.

4. Bad fuel pump. Believe it or not, they have been known to show signs that were described at the end of their normal lifetime expectancy.

Any or all these things may be working together on a 20 year old fuel system!

 

[jenavet]

He said it would crank but not fire, my guess is that the fuel system is loosing pressure at the rails, due to a couple of things.

1. Dirty Injectors allowing fuel to leak down and into the head on top of the valve, where it eventually evaporates.

2. Bad fuel pressure regulator. Leakdown! via evaporative cannister.

3. Bad fuel filter. not enough volume in the fuel rail when it is shut down and the pressure then "equalizes", with the atmosphere.

4. Bad fuel pump. Believe it or not, they have been known to show signs that were described at the end of their normal lifetime expectancy.

Any or all these things may be working together on a 20 year old fuel system!

if the starter or starter wire was bad,the car would not crank at all.....and from my experience with a fuel problem,the car would run improperly and would also trigger an engine light...because the system will sense a lean mixture/lean condition...i still say its a bad ignition module...but i am no mechanic...just goin off what happened to me in the past...exact same problem..........and the only way you are gonna fix it is check spark/fuel when the problem is occuring

 

[christer130]

Thanks for all the info guys. I think that it must be an ingnition problem because there is no check engine codes. This wouldn't be something to do with the dreaded VATS I keep reading about. Would the engine turn with the VATS in security mode? I guess I got some more checking to do.

 

[WhalePirot]

Welcome, new owner!

Rising fuel pressure can be checked at key turn-on. If the pressure does not rise, as it should with the 5 second 'bump' at each start, either the pump or the relay might be failing. Once the engine has oil pressure, it will allow the pump to run via a slightly different circuit. (Actually, I am having a problem like this, right now.)

Alternatively, check for spark at non-start, the same old way you always did: Ask a 'friend', wearing wet shoes, to hold a plug wire while you crank the engine over.

Check the simple things first, before getting into the VATS.

I recommend getting a Helm, Inc. manual for your car, a fuel pressure gauge plus a digital VOM, in addition to any 'normal' car-guy tools. Even if you do little work, understanding your car in greater detail can save you some repair rip-offs.
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