97 toyota previa. Sometimes it doesnt like to go up hills. Runs great on the flats. We thought it was an electrical system issue - replaced plugs and wires - no help - replaced the cap and rotor and it ran great for 2 days. Then back to being sluggish going up hills. Checked the coil and it was out of specs so we replaced it - 1st one we bought was also out of specs but they told us to put it in while they ordered another one. It ran great for a day and a half and then sluggish again... put in a Toyota coil that was within specs and it is sluggish. Engine and Transmission are running smoothly... just no power up the hills. I suppose it could be the transmission but I dont know why it would have been good after messing with the power systems... coil wire tests great. Any suggestions are welcome...

SOURCE: low compression in #1and #2 cylinders 1993 eclipse gs 1.8l

burned valve is likely the culprit.... or bad rings.... hook air up to that cyclinder one at a time.... and listen where the air is escaping... be aware that the motor will rotate till the piston is at the bottom of it's rotation. if it's a burned valve you will have to remove the head and replace it but somewhat easier job then replacing the rings. darn almost forgot.... it can also be a blown head gasket.... same procedure but you might need a brush and some soap water to test for an air leak at the side of the head. when you are done spray some wd 40 on it to get the water off so the spark plugs do not arc.


Robert

SOURCE: 95 GMC Jimmy 4.3l W vin rough idle

My problem was solved when I repaired my 4 wd activation dash switch. The switch was contacting on 2WD & 4HI at the same time. The front differential activation is vacuum activated possibly creating a tug of war that didn't actually engage it but drained off vacuum from the engine? A theory at best but stumbbled across it because I knew the switch wasn't working properly I repaired it and low and behold rough idle disappeared and all is good for 3 weeks running.

SOURCE: no fuel no spark 1990 k5 blazer 350

Take off the distributor cap. Check the star wheel that is splined to the distributor shaft that the pick-up coil uses. Make sure this wheel is not loose on the distributor shaft. It is right above the pick-up. If it is loose, replace the distributor. This is a common problem. If it needs one, all the part stores stock the distributor.

SOURCE: 2001 focus. Replaced plugs, wires and coil pack.

Have you replaced the timing belt? if not i would highly recommend doing so. these cars need to have the timing belt replaced before it breaks otherwise it can and will cause major engine damage.

SOURCE: 1998 dodge ram pickup 318 eng.

If the engine seems to run fine over 1450 RPM maybe there is a vacuum hose leaking or EGR valve is slightly stuck open. Any help from the OBD II trouble codes? Or is there simply no MIL and no stored information in the OBD II computer read at the local parts store through the connector by the drivers knee?