Here is the long and short of it. After getting a job in Alaska I had to travel cross country from San Antonio, TX. I took my 95 3.0L Montero in for a "tune-up" and I think it got tuned down insted. They replaced all belts, hosses, fulids, flushed trans. changed timing belt, plugs, wires, fuel filter, cleaned injectors. Anyway, when I pick up the car they inform me that its seams to run on only four cilinders untill the car warms up and then its fine. It ran great when I took it in! They say maybe a coil pack is going out. We take the car to the dealer they computer it and say that its some sensor that I end up relplacing for some ungodly ammount of money of course. CAR RAN JUST AS CRAPPY! Now I had to go to alaska so I limp up to alaska and now were to date. The car also while idling tends to drop in rpm and then jumps back up again. What the hell!! This week I replaced a coil pack, one of three, found out which one by taking off the wires while car was running and replaced the non-firing one. Helped a bit. Car still has no power, hard to start untill I hold the rpms at 3000 for a few minutes. Then while going down the road when it shifts down the car seams like its not getting enough gas and stutters. Replacing the oil and fuel filter again on friday. Any guesses out there. Or a lot of guesses, hell make up something if it sounds good.

 

Intake manifold (plenum) leak?
Improper installation of the spark plug wires?
Loose electrical connection on the injectors?
Check for computer codes.


That truck does not have OBD II, so there are not as many codes stored by the computer. However, since the problem happened imediately after servicing, I would think it would relate to an error during installation.

 

Well I checked the wires fairly well when I put on the coil pack, checking the electrical connection on the injectors I can do but I have no idea where to start on a intake manifold leak is it something a simi mech. inclined guy(me) could do or would it take some time and knowledge of the professional type. On the install mess up I really beleive they might have done something yet I took it back and they couldent figure it out. The place that I had it done at is fairly dependable.

 

I had this same problem on my 97 montero, It turned out to be the the indicator on the Timing belt i think it was on the camshaft possibly. I had all the same symptoms and that was the problem hope this helps! It ended up costing me $798 Though not cheap!

 

did a tune up on my 97 montero sport, myself, ran like crap at idle. took me a while to figure out but i reversed to vaccume hoses when i put it back together, one was theEGR valvewhich isn't supposed to get vaccume at idle, threw everything off but only at idle. switched it back and fixed the problem.thought i'ld throw that out there. hope it helps

 

[align=left]Had a similar problem with Montero Sport. I always look at vacuum hose's when idle problems, and power drops come up. ( no matter the make) It was the cruse control hose. With automatics, if it won’t shift its usually vac. Hose. Find out what the Vacuum should be on your Montero find a vacuum gage. If it’s low on Vac. Check ALL the hose. If still low it sounds like intake leak (as another guy mentioned). A old trick to find the leak is to spray starter fluid around the seal.Just a little at a time. If the idle go’s up that’s where the leak is. Hope that helps good luck.[8D][/align]

 

Sounds like an airleak post-MAF.

 

the dealership just wants your money....

 

i made that mistake reversing the egr hose. took me a couple of hours to figure that one out. assuming its not a vacuum leak or faulty brand new hardware. my guess would either be they screwed up the firing order. not to difficult to fix since its stamped on the intake penum lined up with each plug wire or the mechanic made a rookie mistake when installing the timing belt and lined up the the marks before tensioning the belt and once the belt was tensioned didn't notice the marks were a couple of notches off which if one cam weren't lined up right would explain why half your engine doesn't seem to work right