So I got this hesitation from idle to about 3000 rpms. After 3k it was fine. I wasn't really that concerned with it, but I changed the plugs and it went away for a day. The next day it came back and progressively got worse. There was hesitation through out the RPM band and a loss of power all the way to redline.

Today I checked the plugs and they are all firing, I changed the fuel filter and nothing. I changed my air filter (it was nasty..) and reset my ECU(unplugged the battery for 10 min) and it fixed it..for about 10 minutes of driving then it came back again... but not as bad as before, just bad hesitation until 3k then just the slightest hesitation from 3k to redline.

I figure it’s either my wires(next to buy tomorrow) or my coil pack. But why would the car run right after the plugs and air filter? I've got a trip planned for next Fri and I don't want to go if my car is still not acting right(9 hour drive one way).

Any other ideas? I'm running out of time and money.

Thanks,
--Tim

I had this problem on a winter beater I drove a while ago. It was the fuel filter getting clogged constantly. I changed it, and it went away for an hour. Then another one, and the same thing for an hour.

Ended up being crap in the gastank. Pop your back seat out, and the fuel pump and take a look in there. If there's junk either in the tank, or on the fuel filter sock, there's your problem.

If all looks good up there, the problem is most likely spark related (plugs, wires...etc)

Brian

Red 97 Eclipse GS (420a) MTX
Custom Garrett T3 Turbo system
Megasquirt w/52 lb/hr injectors & a Walbro 255
Kicker/Alpine Audio (3 amps, 2 subs)
90 Cav 2.2 TBI auto (winter) <- yeah, it's fast

Wires. Then check the tank. And do yourself a favor and get the $40 Bosch wires from Autozone. Lifetime warranty. I've replaced three sets for free just because it's that easy when trouble shooting.

try the ect sensor. It's a possibility. should be about 45 from autozone.

its 85% likely to be your spark plug wires. I go through the same exact thing about once every 9 months.

I thought low rpm hesitation was a fuel issue.
IMO check the fuel pressure at idle.
maybe clogged fuel filter/bad pressure regulator.

1998 dodge avenger 4 cyl AT
Mods are:
Not enough