renix sputters while driving

[alleydog]

I hope it's ok to ask for cherokee help here, as I also have a comanche too. I have an 89 xj with 4.0 renix. It starts up fine and runs good under hard accel, but if I just cruise along with light throttle, it pops and bangs out the exhaust. It seems as if I have to be moving in drive for it to act up. It won't do it while power braking setting still. I have a new fuel filter and plugs and wires on it already, nothing changed. My 89 comanche runs great, I'm thinking about changing a bunch of parts between the 2,at least I won't be buying a lot of stuff I don't need. Thanks,Mark

[big66440]

Try cleaning/testing your egr system sounds like thats the problem to me.

[JeffN]

put a fuel gauge on it, see how fast it comes up when you turn the key on, and how fast it drops off when you turn the key off.

I had the same problem and it turned out to be the hose from the fuel pump to the sending unit letting fuel blow by it.

[alleydog]

Ok, I'll check into both of those tomorrow. It's a sneaky problem, kinda comes and goes. I'll let you know how it's coming along.

[Eagle]

Oxygen sensor.

[carnuck]

Loose intake manifold bolts or a cracked spark plug or cap (even new they can get screwed up)

[alleydog]

I never thought about the intake bolts, This morning I caught it in the act, it was missing under a power brake load,sure seams like an ignition miss. I think I'll put the cap and wires from my Comanche on and if that isnt enough, I'll keep on going!

[immortal]

I had the same sort of symptoms on my '97 XJ... TPS (throttle position sensor) was the culprit. $40 and 6 minutes later... alllll good.

[alleydog]

Well, I think its fixxed. I had an extra throttle body in my collection, so rather than switching the tps, I just put the whole thing on. Runs like a charm. Thanks for the help guys!