Help!...back fires and sputters under load...

SO my 88 pile o'crap is now running like shizz... it starts ok...idles ok...but when giving it gas, esp in gear the thing is just sputtering and backfiring...occasionally the motor will die. I haven't a clue what is causing this...it seems like it started once it got up to "opperating" temp-warmed up. any ideas? I was supposed to go wheeling in the morning....:bawl:

chris

its an '88 renix w/aw4

If it drives OK for the first minute or two while it warms up from a cold start, then one of the temperature sensors is going bad. The IAC, Intake manifold Air Temperature sensor and or the Coolant Temperature Sensor. If it is all the time, the I would say the TPS, Throttle Position Sensor is bad. They can all be easily tested with a multimeter, ohms and dc voltage scales. The testing procedures are posted here in this forum's threads already and in the Renix FSM.