no power

[kurp]

Problem vehicle is a 97 explorer 4L OHV 4X4

Sometimes power is normal sometimes not. When it is not, rpm seems "stuck" at about 3000 and will not increase. Idle is a bit rough. Idle is also quite high when started initially but settles down after a few minutes. When throttle is about 1/3 open a hissing noise can be heard from under the hood but only when engine is under load.

I have changed:
fuel filter
air filter
spark plugs
plug wires
had engine scanned for codes - none showed
checked for vacuum leaks - found none. gauge read 20-22 in Hg and steady.

I give up! any suggestions?

 

[Jason_25]

First off, clean your MAF. If that doesn't help, check the fuel pressure. But I'm kind of thinking that if may be your FPR getting stuck.

The hissing sound is your IAC, but that is not causing the problem.

 

[SaleenEXP]

Originally posted by kurp
Problem vehicle is a 97 explorer 4L OHV 4X4

Sometimes power is normal sometimes not. When it is not, rpm seems "stuck" at about 3000 and will not increase. Idle is a bit rough. Idle is also quite high when started initially but settles down after a few minutes. When throttle is about 1/3 open a hissing noise can be heard from under the hood but only when engine is under load.

I have changed:
fuel filter
air filter
spark plugs
plug wires
had engine scanned for codes - none showed
checked for vacuum leaks - found none. gauge read 20-22 in Hg and steady.

I give up! any suggestions?

I was going to say check for a vacum leak if you heard a hissing sound, but if you didn't find one..thats weird, not sure whats wrong.