My 1988 8 cyl tpi engine keeps turning over but does not catch and fire up. I am on my second battery.

I have air and spark.

I have fuel pressure to the fuel rails and to the cold start injector but the cold start injector itself does not seem to release much fuel. I pulled it from the intake manifold to see how much fuel it was squirting - not much - maybe a few drops for five seconds of cranking. Could the cold start injector be bad after 120,000 miles?

I have changed cap, rotor, wires, plugs, fuel filter, fuel pump relay.

When i pull the spark plugs they are wet with fuel.

This problem gradually got worse over the last three weeks as the weather got colder or as whatever part is broken got worn.

I used to just look at this car and it would start. I could stand outside the car - turn the key and it would start - not anymore.

The starter is engaging the flywheel as all the pulleys rotate.

It was minus 20 celcius here in toronto this morning. In farenheit that means don't lick anything metal.

Help!

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Oh yes and the car has been getting harder to start even when when its warm. It is not catching right away like it used to.
http://members.home.net/mmaker/welcome.htm

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MMaker,

-20°C... Brrr! (That's -4°F for us Yanks). It's only going to -20°F (-29°C) here tonight, so bring it on down to Wisconsin/Illinois to "warm up" and I'm sure all your cold start problems will disappear.

Seriously, If you plugs are wet with fuel, the lack of fuel probably isn't the big problem. You may have too much fuel or a fuel volatility problem, or the pressure at the rails may be a little low. The Cold Start Valve emits a constant rate of fuel depending on temperature. The maximum cold start pulse is eight seconds. The control is done by the cold start sensor/module at the front coolant crossover of the intake manifold.

You should have seen more than "drops" of fuel from the cold start injector, but the engine needs to be cranking to activate the control. If the fuel was dripping from the injector without cranking, the injector is leaking down. At 120,000 miles, I would suspect a freshly cleaned set of injectors would be beneficial.

This leakage would explain the wet spark plugs and hard starting, since your engine floods every time you shut it off. Since the air temperature isn't high enough to quickly evaporate the excess fuel, it remains in the cylinders. The best way to check for injector leakdown is with a fuel pressure gauge. If the fuel rail pressure drops off within fifteen minutes after shutting off the engine, you have either injectors or a regulator leaking. Given your symptoms, I would suspect the injector(s) are the cause if you find pressure leakdown.

If you determine the injector(s) are leaking, check with Cruzin' Performance. They do excellent work at very reasonable prices.

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Later,
Vader
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"No matter how hard you try you can't stop us now"
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Vader = thanks for your response.

When I did a fuel pressure chaeck about two weeks ago the pressure fell off about 15 seconds after the ignition was turned off.

The injectors have about 35,000 miles on them. They are not OEM.

How would i check for a leaky afpr?

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MM,

The FPR can be tested for leakage by blocking the fuel return line from the regulator to the tank. If pressure still drops with a blocked return line, either the fuel pump checks are leaking (not likely if you are getting adequate fuel pressure) or the injectors are leaking.

If the pressure holds steady with a blocked return line, but drops with an open return line, the regulator is probably leaking through.

Vise-Grip makes a special locking plier with rounded jaws to pinch lines without damage. You could also remove the line and install a fitting to plug the plumbing, but that would probably be more work.

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Later,
Vader
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"No matter how hard you try you can't stop us now"
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Those fuel lines look like steel to me.

I retested the fuel pressure it holds and does not fall off. Maybe i didn't have the fuel guage 100% tight on the schrader valve last time i tested it.

Anyways third day without being able to start it.

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Update - I retested the fuel pressure and it started dropping after 5 minutes and took a few hours to drop to zero - so i am inclined to think the injectors are leaking - when the car sits overnight the cylinders flood with fuel. If the car only sits an hour or so it can still be started relatively easy because it hasn't completely flooded. I have now removed the injectors for flowtesting.

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Last post on this topic - I removed the fuel injectors, took them to a shop for ultra-sonic cleaning and flowtesting and put them back in the car tonight. Car runs like a dragster now - the buttmeter says much better than before.

Plus it started right up.

Thanks Vader for your help - without your input i would probably still be waiting for a diagnosis from GM. Thanks again.

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