Intermitant Check Engine Light

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Dec 11, 2000 | 02:52 PM

jimshad

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Intermitant Check Engine Light

My "Check Engine" Light on my 1992 XLT comes on intermitantly. Some times it comes on & off on it's own & then it also comes on & doesn't go off till I restart. Sometimes at idle hot and or cold it will "Lope". I have replaced the o2 sensor after I had the shop determine the code indicating it was faulty.(That was last month, but I drive alot & have gone past their warranty mileage for the scan.) New Fuel & air filters, plenty of oil, New 195 degree thermostat-using 93 octane & now "Outlaw" fuel injector cleaner in the gas tank. I just dread taking it to the shop again if its something that I have overlooked. Any one have any ideas??

Dec 11, 2000 | 10:07 PM

rowiebowie

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Intermitant Check Engine Light

I have the same problem on my '95. Seems to run fine, but pesky light comes and goes (mostly goes) regularly. I tried 93 Octane fuel and no luck. I've got new plugs, PCV, air filter and fuel filter. Hope someone has a solution.

Dec 11, 2000 | 10:54 PM

PAUL_2

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Intermitant Check Engine Light

Check the fuel pressure to begin with & make there are no intake leaks or any unmetered air entering the engine . How often are you using the Outlaw stuff ? Over use of any fuel treatment can lead to more problems than it solves .

Dec 12, 2000 | 10:18 AM

jimshad

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Intermitant Check Engine Light

Fuel pressure as in a faulty fuel pressure regulator?? I have never used this Outlaw fuel Injector cleaner before. I am guessing I may have picked up some bad gas or have some water in it. Maybe the EGR valve is sticking, but where is it located on a 4.0L?

Dec 12, 2000 | 10:54 AM

PAUL_2

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Intermitant Check Engine Light

Fuel pressure problems can range from the pump to the filter to the pressure regulator . Check one system at a time otherwise things become confusing . Why do you suspect the egr is the problem ?

Dec 12, 2000 | 04:35 PM

jimshad

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Intermitant Check Engine Light

I feel it is the EGR because my fuel consumption has gone from 14-15 around town now to 10-12. (I keep it well maintained & would like to figure this out without having to leave it at a shop for a week). I am not using any water meaning I don't suspect a blown head gasket, but I am seeing a lot of water dripping from the exhaust. My guess is this: I have a tank full of bad fuel laced with WATER & the water is causing the fuel system components to malfunction. The water is evaporating which answers my excessive fuel consumption question. Sound about right?

Dec 12, 2000 | 11:52 PM

PAUL_2

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Intermitant Check Engine Light

Water vapor is a by product of combustion . During this time of year it doesnt evaporate as easily as it does in warmer temps thus you see more of it exiting the exhaust system . With all due respect , youre theory is inacurate ...Heres why , If you have enough water in your fuel to cause problems then its likely the problems will be more severe , such as no starts , hard starts or general driveability problems . In short , the engine would perform far worse . A malfunctioning egr valve presents more problems than lowered gas mileage . As I said before , diagnose one system at a time before you suspect another otherwise all you do is throw parts & wasted time at the problem .