suburban stalling out.. help please..

so since I bought my “new” truck, I need to dump an older one.. I have a 94 that suddenly, is stalling out.. for the past 5 years, it has worked flawlessly engine wise.. and one morning, its floods.. I have taken it to two different mechanics, neither or whom, know the problem. one said it was bad gas.. put sea foam in it.. it will idle just great. but you step on the gas, and it chugs, and may or may not quit.. but when it runs, it runs like a swing machine.. TOP NOTCH.. and the main reason I am dumping this one, is that who ever ‘reinstalled” the running board on the passager side, is missing a brace, and my wife can’t use it to step on to get in.. other wise, its TOP NOTCH.. and about 30 or 40 thousand miles less then my other suburban.. tows the boat with a ton of power.. or did all last year.. so guys, please help, other wise a good truck, 4 wd is going to get crushed..

This is just a guess but I’d start by checking the fuel pump.

X2 on the fuel pump.It could be going.

Another thing to check is a collasped fuel line. It happens once in a while.

Sounds like the fuel injection module. My truck acted the same way – ran great most of the time, but off and on the engine would start choking out. It usually happened when starting it, and it would clear eventually if I revved it a while. Not that expensive to fix as I recall.

Good luck.

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X2 on the fuel pump.It could be going.

Another thing to check is a collasped fuel line. It happens once in a while.

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I agree that is sounds like it’s an issue getting fuel.. It’s worth a try to replace the fuel filter and hope that is was causing restricted fuel flow

Yes check all the cheap stuff first.

im a mechanic and if its NOT the fuel pump i would be shocked!!

Had the same problem with my Yukon a couples years ago. Thought for sure it was the fuel pump.

Cleaning off the Mass Air Flow sensor fixed it…

can I ask if its the fuel pump,how can it flood? the truck is flooding out too much fuel or so it seems. when it stalls out you need to floor the gas peddle to get it too start .and then its a ton of black smoke

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im a mechanic and if its NOT the fuel pump i would be shocked!!

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Agree, those model years are notorious for having fuel pumps go out. I know 4 people that have owned that vintage and all have replaced fuel pumps at least once.

Not sure if that is throttle body fuel injection in that era, but I have had several vehicles in the past where the fuel regulator goes bad. Typically when this occurs the car either runs out of gas after driving alittle or does not start. Typically a vacuum hose switch, if you pull the hose off and gas runs out replace it.

Like I said not sure on that year of vehicle, just mentioning past experience.

X 2 on the fuel press reg.

One other thing to check is the coolant sensor in the intake. Unplug the sensor and look for corrosion… greenish or just rusted bad. If this is the case replace both the connector and coolant sensor. This will tell the powertrain control module its -39 or 40 degrees and will dump as much fuel as it can. This coolant sensor is not the same one for the temp. gauge… that one is in the drivers side head.

Good Luck