My 98 Bonne runs super great and shifts good when cold. Once warm it still has good power but at certain speeds 30 to 50 when you step on it there is an intermittent bog. Sometimes you have to virtually stand on it to get go and a 3 to 5 second delay. NO codes either while parked or driving. I did check coil packs, plugs and plug wires. The only thing that bothers me is that the plug wires from Car Quest shows over 50k resistance. It does not miss not even once. Do you think once it gets warm the wires are letting it produce a very small weak spark thus killing driveability?
Hey Dan your tech posts have been excellent in trouble shooting. Ideas guys?

JP

Drive it hard at night. Then look underneath and see if the catalytic is glowing.

First thought to me is plugged cat. But we need to test that puppy and not shotgun one in there.

I did run it in drive instead of OD for 25 miles very hard and went to dark parking lot and it was not red hot, but after starting it back up and driving off it was doggy again. Maybe the converter is just starting to shows early signs of getting plugged?

The sluggish when hot could be a bad ICM, electronics don't like heat. But first I would unplug the MAF and drive around a bit. It will stumble at first and you will get a SES light. No getting on it with the MAF unplugged. See if that improves anything. I'm thinking a sensor problem right now, like a dirty MAF

Hi Dan,
The TPS & MAF are brand new and I rechecked the plugs wires. OOPs had it on the wrong scale and the plug wires are well within range. This has done this since I bought it 2 years and 20k miles ago. So far nothing done has changed it. I was also thinking electronics. Maybe fuel regulator?
Thoughts?
JP

The FPR is vacuum controlled. I'm leaning towards a electrical problem. A fuel problem the car would kind of sputter and then die. A fast shut down tends to be more a electrical problem. Such as a short, or loose wire. Things like a loose wire on the battery cables can shut a car down in a instant, and then start right back up.

One thing I did notice that after disconnecting the battery when changing out MAF it ran great for 2 weeks and then back to the intermittent boggy-doggy when warm. It never dies or anything like that just like it takes to long time to downshift and even when it does still low on power then good once your moving. Very weird. Computer issue???

Hmm, that'* odd. I would then say have the fuel pressure tested, see if it drops off when the engine acts up.

This also did this before replacing fuel pump which had fuel line leaking on top of tank. Fuel filter replaced already too. Seems like when I disco battery to reset computer it runs great for about 2 weeks. Once this one has fixed I will make all know of symtoms and the fix!
JP

A good scan might be in order here. I had a car here last year that would loose power when turning from a start. Turned out he was getting over 20* of knock retard and loosing all his timing. He never came back so I don't even know what the cause was.