Chevy Impala... Trouble with head gasket.?

Question

I have a 2000 Chevy Impala, 3.4 V6

The car ran great until it overheated and blew a head gasket. Other then leaking water there was nothing wrong with it.

So I took the car apart and replaced the head gaskets and put it back togater.

When I started the car for the first time it started to smoke. The smoke would not go away. The biggest problem is that when you as much of touch the gas pedal or even put on the ac wich revs the car a little, the car starts to back-fire to the point that it just turns off.

Again there was nothing like this before, and this is a least the 10th time I am replacing a head gasket, but I can't imagine what it could be. If you have any thoughts.. please share. Thanks

Answer 1

BACKFIRING>>> this tells me that your spark plug is firing when the exhaust valve is still open a little bit. You say you have done 10 head gasket repairs in your experience, so I'll trust that you placed the new gasket correctly and HAD THE HEADS planed before replacing.
Is the car an overhead camshaft, and some cam/valve adjustment is WAY off? You would also hear a cam ticking noise?? (I'm not familiar with Chevy V6 cams)
But perhaps when the head gasket was bad...one or more valves were very hot due to water loss/cooling problem and they were partially burned. Now it doesn't seat very well in the valve seat.
THAT's my guess. It's hard to outguess Ms. GotSpeed7, with 19 years GM mechanic experience...

ONE HOUR LATER.... just thought of another cause. Electronic fuel injection system is causing it. The car's sensor and firing can only be analyzed by computer at the Chevy dealership. I have this backfiring problem once a month, starting my FI car, reason:the aged BOSCH fuel injection. Two backfires, and then it starts.
WOW!!! and I really like RED'S answer below mine, thumbs up RED.

Answer 2

1.) do a cylinder compression check [all 6 of them]

2.) is the catalytic converter clogged or destroyed from radiator fluid?
a. if the the converter is blocked it will blow backfire through the intake enough to shut it down...

3.) is the timing off or the plug wires crossed?

4.) does the computer need reset?

5.) is the intake manifold cracked?

6.) does the oil still have radiator fluid getting in it?

7.) Does this brainstorming help any?

Answer 3

Ok, first, did you have the heads reworked and surfaced. Are you putting the gaskets on correct...they have TOP printed on them and if not then are you using the correct head gasket set... and if the car is smoking white smoke, then you still have coolant leaking into the cylinders..and also did you change the plugs? .email me back with some answers and I will help you--another thing..is this car FWD

Answer 4

the first aspect your buddy must have finished replaced right into a appropriate diagnosis earlier something. If there replaced into head gasket cloth interior the device an engine flush could were finished. i ought to have suggested replacing the water pump, thermostat and hoses as preventative upkeep. The heads could were despatched out to be pressure examined to make certain they were not warped. that is the right thanks to flow about this. At this factor i ought to flush the cooling device and make confident the device is bled genuine. the three.a million and three.4 are puzzling engines to bleed. there are certain equipment and procedures to do this that you will be able to discover at vehicle Zone (haynes save manuals).there's a bleeder valve on the right of the engine on the fringe of the right radiator hose on the engine facet. the precedence would also be on the temperature sensor that could not turning the followers on at the same time as they are meant to. If the sensor is okay the ECM ought to not be reading the sensor genuine and the ECM ought to wish to get replaced or flashed each now and then.

Answer 5

Timing sounds off, re-install distributor, rotor to #1 when engine is at TDC for #1 cylinder. Verify plug wire routed to correct cylinders and secondary wires are plugged into distributor.

Answer 6

Take the head in and have it checked for cracks or warped.