timing chain tensoner came appart going down the road and bent all of the exhaust valves. we replaced everything and wouldn't start. we were told to put coil packs on it and we did. thought that it was 180 out on the timing changed it and it still does the same thing. fires once and a while and when it does it blows the intake right off the valve cover.
Cannot get cavalier to start after installing new timing chain, exhaust valves, and coil packs?
is your timing right? i think its called a timing gun, or ray gun, something like that, it can help you get the timing right on the car. I'm not a good mechanic but thats what it sounds like to me.
Cannot get cavalier to start after installing new timing chain, exhaust valves, and coil packs?
You need to start over at the begining. Validate the timing mark on the flywheel that equates to the timing mark on the camshaft. Make sure they are correct. Then start down the row, you only have four, have the plugs out and make sure you're getting spark into each cylinder. make sure you have compression in each cylinder. Do your basics all over until you see what you've missed. You have missed something.
i don't have much experiance with cavaliers, but it sure sounds like its not timed right. try moving the chain/belt a tooth in either direction on the drive gear (i think, which ever one is larger).
another less likely possibility is that maybe the rocker arms have bent, because obviosly the intake valve isn't closing all the way when it fires.
Back to basics. 1) Removed the valve cover.
2)Disconnect negative battrey cable (to avoid accidental engine crank)
3) Locate # 1 piston (Front of the engine, closest to the radiator)
4) Removed timing chain.
5)Turn engine by hand (at the engine crank wheel pulley, serpentine belt) While turning, observe the valves. Intake valve open then closed. continue cranking the engine until the valve is even with the exhaust. Note: DON'T OPEN THE EXHAUST VALVE. That would be exhaust stroke.
6) removed # 1 spark plug and verify the position of #1 piston. If both intake and exhaust valve are fully closed. # 1 piston should be at 90 degrees, compression stroke.
7) check you timing mark in refference to the timing chain. The timing mark of the crankshaft and the timing mark of the camshaft should be aligned with each other. Crank it if it needs be until both timing mark are aligned horizontally, then install the timing chain.
8)install #1 spark plug and wire. Verify firing order and install negative battery cable. Try to start car at this point. It should run. If not something is wrong . NOTE: MAYBE THAT THE TIMING CHAIN WAS INSTALLED WHILE ENGINE WAS @ EXHAUST STROKE?
ENGINE OPERATION:
*Intake stroke= intake valves opens and allow air and fuel into the cylinder.
*Compression stroke=Both intake and exhaust valves are fully closed, piston @90 degrees compression,
* Power stroke= Sparks plug ignites air and fuel, forcing the piston downward which is the next stroke
* Exhaust stroke= exhaust valve opens releasing the burnt fuel.
Well I hope this helps, good luck...
