Engine starts surging when warm

[Ex3Cutioner8]

hi. i have a 1995 sho mtx. it has new crank sensor cam sensor timing belt and i replaced the DIS Cleaned the Mass air sensor. the problem is when it is cold it runs really good, but when it gets warm i mean as soon as it gets warm, i will put in in 4th gear at 2k rpm and step on it, and it will surge or kind of buck like a bad crank sensor, the problem starts to go away at 3k rpms, the cel is not coming on, i have checked for vac leaks found one but it did not fix the problem ,and also it has a real rough idle for the past 4 months, the problems don't seem to overlap time wise but you never know, the bucking is new, i'm kind of lost on this one, any help would be great. Eli

 

[nik97]

Try a known good MAF sensor. Cleaning a MAF can help if it is dirty but it wont help a bad MAF. I've recently seen a MAF swap fix this exact concern.

 

[SASHO91]

I'd look towards the ignition system.

 

[Ex3Cutioner8]

alright i will start with the MAF sensor, i have a 3.2 MAF sensor will that work?

 

[Tecchie]

Actually...............

:woohoo: I would take the Air Idle Bypass Valve (the thing on top of the intake that has a 2-wire harness connecting to it and has only two hex/allen wrench bolts in it) off and clean it, but test it first, has to read on your multimeter between 7 & like 12 Ohms... Mine was at nine, but dirty as all ****, so I sprayed some carb cleaner in it until I can see it was swimming in it, and that cleared alot of gunk out of it.....

I had the same problem but usually at idle, it would rev between 1k and 500k and sometimes low enough to make the oil pressure light flicker a bit...

Also, I get the same thing when it's hot and I press on the gas even at highway speeds and it acts like there is no power until I push the throttle to the floor a bit more and then it just lunges...



Hope that helped..