91 explorer rough idle

[navajo91]

I have a 91 explorer i have replaced coil,plugs wires,iac,tps,maf,o2,fuel filter and a few other small things and nothing has changed.it still continues to have rough idle i am about to lose my mind. can anyone help..... thanks

[shorod]

Welcome to the forum!

Have you inspected all vacuum lines for cracks and splits? Have you checked the intake manifold for leaks? Have you verified that the air intake hoses are properly installed and not leaking? Have you checked the fuel pressure? Have you checked the EGR system for correct operation? Have you checked compression on all 6 cylinders? How about checking the operation of the camshaft and crankshaft position sensors, do you have access to an oscilloscope to check these?

-Rod

[navajo91]

Originally Posted by shorod

Welcome to the forum!

Have you inspected all vacuum lines for cracks and splits? Have you checked the intake manifold for leaks? Have you verified that the air intake hoses are properly installed and not leaking? Have you checked the fuel pressure? Have you checked the EGR system for correct operation? Have you checked compression on all 6 cylinders? How about checking the operation of the camshaft and crankshaft position sensors, do you have access to an oscilloscope to check these?

-Rod

it does not seem to have a leak at the intake , compresion is good , I know very little about the camshaft and crankshaft posision sensors could they cause that? It seems to run real good at highway speed. This year does not have egr. i need to check fuel presure yet.i think that might be the main prob it has been doin this since i got it about 2 years ago will a weak fuel pump go that long without goin out? thanks