Pauls 98 SE

At idle the engine is smooth at about 800 rpm, with or without AC. When give it gas to pull away from stop, engine bogs down and hesitates till about 1200 rpm then surges to about 1800 – 2000 rpm. Acceleration is not smooth and surges as long as accelerating. Also acceleration is slower than normal all the way through 60 -70 mph (probably higher but have not tried). This is being easy on gas pedal. I can hold a steady speed on flat road with no surging. Slightest push on pedal and engine bogs, then transmission kicks out of OD and I must push harder and eventually cause a downshift to get any acceleration or to maintain speed on incline. If pushing hard on pedal, the surging is much more noticeable.

Problem started a couple of days ago and is continually getting worse until today the CEL came on while accelerating. Flashes while accelerating and solid when holding speed and goes off when at idle. Checked ECU for codes a couple of times now and LED is flashing 55.

Recent repairs: new fuel pump, new O2 sensor, new MAF sensor

As always, thanks for the input and advice.
Paul

max723

iTrader: (7)

im not 100% sure but check to make sure you dont have any air leaks/loose hoses in the engine such as vacuum hoses

MAXI

i want to say, O2 sensor. if you're interested in checking this......disconnect the O2, start and drive the car, see if the bogging disappears.

Greeny

iTrader: (43)

Check ALL vacuum hoses under hood for leaks. windex is good to squirt on them to check for leaks And look for disconnected electrical connections..

Cliff Clavin

iTrader: (11)

This is kind of a strange one.

Without any codes, it's kind of tricky. Mine acted similar when my coolant temp sensor went out, but it displayed a code for it. My idle also surged at the same time, but my IACV was full of crap.

I suppose you could check the coil packs. They seem to be a common problem in the areas of bogging down and stalling.

Pauls 98 SE

I have been checking electrical connections and vacuum lines, all seem to be good.

Car has started to die if I sit idle too long, like at a long stop light. The sluggishness and surging has become BAD....

Is this the behavior of a failed IACV? The FSM mentions this alot as I read through the problem diagnosis section.

Thanks -- I am in desperate need of advice.

Greeny

iTrader: (43)

If your problem is only at idle then I would suspect the iacv being the problem. I have a good used for sale if you find it to be your problem...