cecilford

1985 5 speed
This has happened twice. Get in cold car, start it up and drive around for a while. Turn the car off and it will not fire. Cranks over but will not start. Tow the car home and hours later it starts with no problem. I'm sure this would have happened more but it hardly ever gets driven. It should be noted that there was a smell of gas coming from under the car when the tow driver took it off the dolly. Thoughts?

aaddpp

Mongo

Turn the ignition key into the on position but do not start the car. With the hood open can you tell us if you hear clicking? This indicates the injectors are working, which is not a good thing. Clicking injectors without the car running indicates an LH failure.

AO

WWJBS? Relay relay relay...

Most common relay to fail is the fuel pump relay. Jumper the 30 & 87 pins of the socket and you should hear the fuel pump run. If it still will not start, then try plugging your FP relay (which is now out of the socket) into the LH relay, then EZK relay.

aaddpp

Would an LH / EZK problem lead to the fuel smell that seems to be coming from under the car? Not questioning, just asking :-)

Cheers,
Dave

Mongo

If the LH fails and fuel is in the lines, injectors clicking with the ignition on can pump excess gas into the cylinders. When cranked, the gas can go out the exhaust valves into the pipes. You will smell gas in the exhaust if this is the case. Worse case scenario is so much gas is pumped into the cylinders, the engine will hydrolock as it cannot compress large amounts of liquid.

PorKen

Check the vacuum lines at the fuel pressure regulator and dampers for fuel. A leaking damper will make it hard to start.

Check the Temp II/coolant temp sensor on top of the coolant bridge (fuel injector style connector). Measure each terminal to ground, should be >1K ohms cold, a few hundred warm.

Bill51sdr

+ infinity. I'd concentrate on the LH relay as LH failure is extremely rare in S3's. I had a similar situation in an '86 and it was the LH relay.

AO

FUel smell coming from under the car could have many possible sources and is a major concern. Depending on the strength of the fuel smell, all things should be considered including leaky fuel lines. There have been many documented cases of 928's burning up due to old, leaky fuel lines.

But fuel smell could also be due to poor/no combustion allowing fuel vapor to travel down the exhaust pipes.

If you car runs okay, but you smell fuel, I'd get to the bottom of it beofre driving/running the car. I've expereiced a car fire (fuel related) 1st hand. Huffing and puffing to try and blow it out does NOT work.

Hilton

+1

TWJBWS!

jeff spahn

And that's why I have a 2.5# halon extinguisher in the car. Just need to get it plumbed under the hood now.

John Speake

LH ECU in an '85 doesn't fail in the "click click " manner of the S4 and later.

As you have a fuel smell, that indicates EZ-F and LH are in fact working, so I suggest that it is flooding.

That could be due to leaky injectors, or fuel in the vaccum system as suggested, due to aruptured damper diaphram.

Next time, try starting with foot to the floor until it fires. To speed it up you could remove the fuel pump fuse until it does fire, then replace the fuse but still keep your foot to the floor until it runs.

cecilford

The car is running fine right now so I'm guessing the relays are ok. There is the smell of gas so I need to have that looked at asap.

cecilford

Forgot to add that I turned the key and listened for fuel injectors clicking. I heard nothing until the engine is running then you can hear the injectors clicking. It does seem like a flooding problem.

Mongo

You could have a damper that failed dumping fuel into the vacuum lines. That can flood the engine making it hard to start when warm. Ask me how I know...