Cherokeex2

I have a 97 cherokee 4.0 automatic, seems to have a hicup? it cuts out but if you floor it runs fine anyone ever have this issue, I have seen alot about stalling etc but this doesn't happen it runs great except the hicup, and only does it for a few seconds then floor it and rest of drive is fine. I have replaced plugs wires iac map sensor pick up coil. soon will do tps and coil, a co worker swears its the computer, he has owned 8 cherokees oh and no codes.

5-90

Search for my posts on "function testing" the TPS - you'll need an analogue ohmmeter.

The TPS is a carbon-track potentiometer that functions as a voltage divider against a reference voltage provided by the ECU. Steady-state cruise operation can gradually compress that particular part of the track - first changing its resistance, then causing a "flat spot" in the TPS response curve. This presents as a "hiccup" - or a spot where the engine "cuts out" until you pass that spot.

Solution? Replace TPS. You shouldn't need to replace anything else.

Symptoms? A "flat spot" or "skip" in throttle response.

(A failed/failing ignition coil would present as an inability to operate properly at any high engine speed, as it wouldn't be saturating properly. It will usually idle fine, and probably run fine up through 1200-1500rpm, unless the coil is particularly bad or shorted through.)

Cherokeex2

Upstream 02 sensor