Head Gasket change on 3.4 - car runs rough after? [Archive] - GrandAmGT.com Forum

PDA

View Full Version : Head Gasket change on 3.4 - car runs rough after?


BTarb24
03-25-2006, 03:29 AM
i just finished changing my head gasket on 3.4. The car fired right up but the engine vibrates fairly roughly, the exhaust has a fast, repetitive, clacking/backfire-like sound. the sound comes from the tail end of the muffler. occasionaly.. once every 10-30 seconds there is a clack sound in the engine. all the rockers are torqued to spec and like i said, its intermittent, not repetitive so i doubt it's a rocker. I used a torque wrench on heads, rockers, LIM and UIM. the valves & springs were left in the heads.

I only let it run for about 1 minute then shut it off and ran it for another minute a little later on. it has coolant and oil. i saw no odd coloring in the front valve cover or dipstick. when you change headgaskets does it take a few minutes for the engine to simmer down? i've never done it before and am a bit timid to let it run without seeking advice. .. no codes are being thrown. anyone have any insight?

lone_wolf025
03-25-2006, 09:47 AM
I assume you had to disconnect the battery to do the work. If so this may be just the computer relearning the engine. I'd say let it run for a little bit and watch your fluid levels closely. If the thing doesn't get worse drive it gently for a little and see if it goes away. That's all I can think of.

BTarb24
03-25-2006, 04:12 PM
I let it sit last night. When i woke up and fired the car up it backfired about 4 times and then quit. i think a valve was stuck open due to low amounts of oil on the rockers after the repair (forgot to lube them up before the valve covers went on.

The engine smokes a bit due to fluids having gotten onto the exhaust mainifolds/heat shields. Does anyone know how long(on average) it takes for oily fluids to burn off a manifold?

BTarb24
03-25-2006, 04:25 PM
There is a repetitive tick coming from cyl 6 tho. What are some of the possible causes of a repetitive tick in the engine? all the rockers were torqued down with a torque wrench and then i attempted to wiggle each rod to make sure it didn't move or have any play.

Do you think i should buy another rocker and try replacing just that?

Do i have to pull the head to replace a valve spring?

digitalballz
03-25-2006, 05:53 PM
It can take a while maybe half hour for all the crap to burn off/out of the exhaust and everything else. Shouldnt really have to lube anything before putting it back together. I havent on any of the head gaskets i've done. As for the tick all the 3.4's have it. Just make sure you change the oil before you start it.

BTarb24
03-25-2006, 06:30 PM
i was talking to a friend and he had the same rough start problem happen to his sti the other day when he put in new injectors. He said it lasted for about 1 minute and then smoothed out. he attributed it to air in the fuel lines. I had a lot of fuel drain out when i depressurized and then even more when i popped the injectors off the rail. i guess logically speaking the system will pressureize when u turn the ignition on, but it will still be containing all the air from when the fuel drained out.

I didn't know about the tick. thanks.