My truck was running one day and won't start the next.

IMAKEORPHANS

MEMBER
1992 GMC TYPHOON
83,000 MILES

My truck has a fresh tune up, good spark, proper timing, fuel pressure at 36psi, with the vacuum hose applied, and ran good yesterday. The only thing I changed in these two days was the gas. The truck was in storage with gas stabilizer for two years. I emptied the tank and added new gas.

The engine is being flooded with gas at start up. The spark plugs are a wet black color and the exhaust is black. I noticed the throttle position sensor was disconnected and reconnected it. Afterwards, I cleared the ECM of codes by removing the fuses and tried to start it. I can't get it running long enough to check for more codes. Please give me some ideas of what to look for. I don't know how to disengage electronic choke if exists.

3 Replies

JACOBANDNICKOLAS

MECHANIC
108,164 POSTS

Pull the fuel pump fuse and see if it will start. You may have sticking injectors.

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Thursday, October 13th, 2011 AT 10:51 PM

IMAKEORPHANS

MEMBER
24 POSTS

Wow, I disconnected the fuel pump and the engine ran longer than it has all day. What next?

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Thursday, October 13th, 2011 AT 11:45 PM

KASEKENNY

MECHANIC
18,907 POSTS

More than likely you have a leaking injector or another reason the engine is flooding. However, we need to start with trying to start the engine in what is called a clear flood start.

I am attaching the info below but by holding the throttle to the floor when starting the engine, it will cut the pulse to the injectors and so that it leans out the mixture. If you have a flooded engine, it should start after it cranks for about 5-10 seconds.

https://www.2carpros.com/articles/car-cranks-but-wont-start

Also, we are going to have to pull the spark plugs and take a look at them. If there are injectors leaking, then I suspect the plugs are fouled at this point and will require replacement.

If you don't replace the plugs, then you may fix the issue, but the fouled plugs will still not start the engine.

Please see the info below and let us know what questions you have. Thanks

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