My 98 w/ 147k, the 3.5L, auto and 4wd runs smooth, gets 18 - 24 mpg, shows no CEL but is gutless in 3rd and 4th gear between 2000 and 3000rpm. The plugs and wires are new, the air filter is new, the tires are the right size, no oiluseage or blue smoke, but she has no cahones. My next guess is to clean the injectors. Any other ideas? Could it be catalytic converter or o2 sensor and still not throw a CEL? Some quirk about living at 7000 ft above sea level?

 

Did this suddenly happen or has it been slowly getting worse?

I'm sure you would have noticed it but just in case, if it suddenly started, are you sure you don't have the transmission "Hold" switch turned on? The symptoms are similar.

Ron

 

Thanks, Ron...interesting suggestion. This car has been gutless since I bought it with 134k 18 months ago. The hold switch itself is not actuated. I suppose it's possible that the switch is shorted to "hold", and I could circuit test it. I thought hold simply negated 1st gear. What more do you know about "hold"?

 

I don't know that much about it. I agree that the supposed purpose is to negate 1st gear but I have had it happen twice that I suddenly found the truck to have no power or acceleration in any gear - it felt like it would not kick down to a lower gear at any speed. Then I noticed that the hold switch was on because I had set something on the console. Turning it off was like a day and night change.

If the switch is on there should be a warning lamp on the dash - but those can burn out. You might want to take the dash module out and confirm that the "Hold" lamp is working. If you and your mechanics can't find any fault with the engine it may be worth having the transmission checked for error codes.

Ron

 

you need minor overhaul and major tune up

 

Check your MAF sensor. If the barometric pressure sensor (built into the MAF) is faulty, you may experience problems such as the ones you describe. I would also get the TPS checked with an ohmmeter.

 

skiddy, good advice on MAF and TPS. Will do.

 

after a year of sleuthing, I waved the white flag and let a seasoned veteran at automasters in cortez CO try the diagnosis. He discovered the crankshaft pulley bolt for the timing belt was loose. I took it apart and discovered JB Weld and damaged threads inside the crank, and the key on the pulley was nearly gone. The gear / pulley was wallowing and dynamically retarding the timing. Mitsi had issued a TSB on the defective bolt design. Feels like a new car now.