dazed and confused

[mjatondo]

about a moth ago my 1993 ford explorer xlt .4.0 6 cyl suv started making a a popping sound under the hood .like a muffled backfire.i put in a bottle of lucas problem was gone .a week later same thing again with idle low.so i changed spark plugs and fuel filter .problem stopped .for a few days.began to get progressively worse .no check engine light .began fuel odor and very bad gas mileage .i replaced the iac valve (new) started running perfect for about 10 minutes.all in all ive tested maf sensor ,tps, and looked for leaks.i haven't ran it on the computer tester because no check engine light.one thing i can add my temp on dash doesn't seem to be working right never goes above the first line .also my heater barely gives off heat.at present the car stars but wont run unless i pres down on the gas.and stalls most of the time i let it off ...someone help please

 

[ppbskis]

Your symptoms are quite similar to mine. My 92,auto, 120,000miles had check engine light come on while highway driving. Took to shop code for 02 sensor was indicated along with several other unknown codes. When I started it cold it would pop and gurgle and almost stall until warmed up. Gas mileage went from 20 mpg plus to 10 or less. If I went to a drive thru window it would almost stall out and at times would, but at speed it was not noticeably different. I wish I could tell you what was done to fix it other than the mechanic who went through all the typical troublsehooting, afm, tps, etc. told me that he sent it to a specialist who reprogrammed the ecu. Hope this helps.

 

[1Byounkin]

Check the fuel pressure regulator (FPR). Pull the vacuum line and see if there is gas in it. If there is you need to replace it. Maybe, raw gas is being sucked into the intake.

I'm not sure about your heating problem, but could be bad sensor and/or blockage in the coolant system, causing it to run rich. Acting like a choke, by telling the engine to dump more gas into it. It might think the engine is cold. Their are two temperature sensors, one for the gauge and another for the computer. But since you don't have heat, check coolant system. Might be blocked heater core, if your not feeling heat in the truck.

 

[mjatondo]

im gonna try the check for leaks trick .

i

 

[mjatondo]

update... update....

ok i replaced the iac valve yesterday and it was shutting off... last night i disconnected ground from battery since i read about computer having to reset.
i did the carb cleaner around intake thing no leaks.computer was reset.was running with idle super low at first but not turning off.took it on a five mile drive no problems and not turning off..there is a big hole inh the air filter box .do i need to replace ?

 

[1Byounkin]

If the hole is above the filter, than yes. If not than no.

Did you figure out the heating problem?

 

[mjatondo]

it is above the filter

when i move it around it makes a putting sound ....???

 

[mjatondo]

Second update

Purring like a kitten ... No black smoke ...so sputter... No stall..


For now .




Test drove it around town let it idle etc.rpm stable ..


So looks like for me ...

Replaced fuel filter

spark plugs

added lucas fuel injector cleaner

cleaned mass air flow sensor with (maf)approved cleaner

cleaned idle air control - replaced (didn't work)

bought a voltmeter tested all sensors ohms and voltage.

Purchased (iac) new ...two year warranty ... At auto zone 65.00

reset computer and bingo problem fixed