engine running rough

[jsoule]

Hi There i have a 1993 ford explorer XLT and i have been having engine problems and i'm lost. The truck seems to bog out the whole time i drive it and there is some power to the vehicle but not what it should be and when it warms up after a little bit (6min or so) the RPM's start to fluxuate between 1000 rpm's-1500rpm's and i will have next to no power so i have to put it in park and let the rpm's keep fluxuating then the rpm's go to 1200 rpm's and it will start running like i first started it. so i need help bad cuz i barely get 10 mi to the gallon.
Thanks Justin

 

[bigdaawg01]

Couple of suggestions,
first, check the IAC valve on the intake manifold, when electricity is applied it should open and when taken away it should close. If this is dirty with black sludge from the PCV system it will stick open and lets raw air go around the throttle body. That is what makes the system run at a higher RPM on a cold morning. Easy to clean if $40 bucks is an issue, but not 100% guaranteed.

second visually check the O2 sensor for damage or a think black coating of deposits. Something normally is wrong to make this Sensor go bad. Like an emmisions or fuel problem.

Third, check the Coolant temp sensor ($14) for the computer not the one for the guage. This sensor tells the computer what temp the engine is running. if it is telling the comp the engine is cold it will rich the fuel and then you will have bad gas mileeage and loss of power from to much fuel.

Fourth, check the fuel pressure regulator for a vacuum leak. if you hook up a hand vacum pump you can make the fuel system fluctuate on your own. If the diaphram is bad the guage will leak down on its own. Hope this helps..

 

[Louisortiznj]

I had same problems simimlar to yours and I changed the o2 senors 2 top ones and then it kept stalling out . It endend up being a leaking elbow. So I put my ear over the engine and heard like a sucking noise when I put my finger on the hole it started running good. So long story short I cut the elbow off with snips and went to auto zone to try to match it up . i cut it to fit put some clamp now she purrs like a kitten .