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Discussion Starter · #1 ·
Help!

I have a 91 Suburban that I am having some troubles with. If you can bear with me through the story here hopefully someone can give me some insight!

The car sat for about 2 years without moving before I wanted to take it offroading. I threw 5 gallons of fresh gas in the thing and presto, it started the first time without any trouble and I took it for 400mi of offroading. Once again it went in to the backyard and sat. Another year passed and I went to start it and it wouldn't start. I ended up droping the tank and finding the little rubber hose that connects the fuel pump to the metal pipe split. I replaced the hose and again took the car out for another 750mi without any troubles at all. Again, it went to the backyard. Here it is about a year since then and I went to start the car.

The car cranked over and presto, started like it always does - idling perfectly. I got out of the car and started to windex the windows and clean some of the mess up when after running for 5-10 minutes it just stopped. I went an cranked it back over, and again it started - ran for 20 seconds or so and again stopped. Now whenever I crank it over it cranks for about 5-6 seconds, then starts, runs for 1-2 seconds stable and then all of a sudden stops.

I took the air filter off and I can see the fuel injectors dumping lots of fuel, I almost want to say too much fuel? After cranking the car a bunch of times the entire car wreaks of gas... One thing I notice now is if you hold the gas pedal down after cranking it for a while you can see smoke in the chamber below the butterfly valve. Not sure whats causing this?

Car had about 1/4 a tank of gas, so I threw another 5 gallons of fresh fuel in it to see if that was the problem. Same thing happens. I'm up for any suggestions, I have no idea where to start.

Thanks guys,

Jason
 

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Are you using any fuel stabilizer in the car?? First thing I would do is a new fuel filter. Then remember, TBI system is sensitive to fuel pressure changes! The bad gas might have clogged your pressure regulator, and that's why it might dumping fuel!! Check the fuel pressure and take it from there!!
Hope this helps!
 

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Discussion Starter · #3 ·
I tested the coolant temperature sensor, and it tested good. Replaced it anyway and it did not help, same problem. The fuel injectors are definitely pouring too much fuel in the engine. What other components would cause this?

Is there a procedure to test the fuel pressure regulator?
 

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MAP sensor. If the sensor is screwy it will tell the truck to dump more fuel in than it needs. You can back probe it to make sure.
 

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i still go with bad gas........dump the tank into a lawn mower and use fresh and a new filter and SeaFoam the tank and intake system. then see how she does......mike
 
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