I put a new head on my 94 pickup. When the engine accelerates it hesitates a little. When the engine accelerates while the vechicle is on the road the problem becomes more severe. It hesitates bad and backfires. It's not a loud backfire, but you can hear it in the engine. It seems as if it's not getting the right spark or there is fuel problem. The new head is a little more high performance and included a different cam than the stock. I set valves at a different lash as instructed in camshaft installation. I put the new head & timing on because it blew a headgasket. The catalytic converter melted during the blown headgasket fiasco.

im installing an new street rv head w/ a torkr cam on it, and a new timing chain set all from eb right now. i hope that doesnt happen to me. where did you get your head from? did it come preassembled?

I got the head from Sunwest out in the pacific northwest. Everything went pretty smoothe and I am pretty sure it all went back togther right. I am hoping it is something fairly simple.

Bummer guy. Warped head, or bad block decking, or bad headgasket install, or any combo. Do you need to add a little warter/coolant every other day or so? I do, because water is getting into the combustion chamber and burning off. My heater don't blow hot half the time either. That's my sputtering anyways. Good luck.

Hesitation on acceleration and backfiring would indicate a timing problem to me. Did you set the ignition timing properly using a timing light and the paper clip in the diagnostic box? Could be a few things...to hot of a cam profile, binding spring etc.

Any difference in performance from cool to warm engine??

~Darin <img src="/forums/images/graemlins/baby.gif" alt="" />

Just a thought, check the O? sensor. my runner ran all messed up when it went bad. it would run fine then once I gave it gas it woud either go or feel half power, kinda like it was missing.
if the head gasket failed the sensor could have been damaged from the coolant...........Karl

The engine is starting to overheat now. Could this be a problem related to fuel mixture, the catalytic converter, or the O2 senser, or all three combined? I replaced the cat during the head installation b/c it melted. I've been reading where the wrong fuel mixture can create blockage in the cat and cause overheating. I am afraid the headgasket didn't go back on right or there is something wrong with the block. Would that cause overheating? I have replaced the radiator, water pump, thermostat. The engine is running like it got water in the distrubuter. I am not noticeably losing any coolant through the radiator.

it may be a air pocket in the cooling system. make sure it's Burped. and the O? will make it run lean or rich. if you melted the cat check the wires for the O? that they aren't shorting out.............Karl

whats the proper way to "burp" a engine.

when I put my hand down by the tail pipe it gets moist and I've noticed a little water dripping out of the pipe. My buddy said his truck does that also. It smokes a bit out of tail pipe when I first start it up, but it did that even before I blew the headgasket. The smoking stops after it heats up. I've noticed a bit of a knock in the engine at idle speeds. Is this a sign of the timing being off? Where is the mass airflow sensor at?