Knocking issues 91 5.2
tubadave
08-19-2007, 04:48 PM
This all started with my upper radiator hose bursting on me - had to drive about 1/2 mile after to a auto place to find hose. I replaced the hose and stat contunied driving and engine started overheating again.
Yadda yadda
When starting, engine would begin knocking horribly after about 3-4 min and mucho white smoke would come from exhaust (burning antifreeze) Noticed water/antifreeze was mixing with oil on oil change (looked like melted chocolate icecream - very bad). Tore engine down to heads and noticed a compromise in the head gasket. Got heads rebuilt and replaced gaskets.
Now on engine start:
1. Engine idle wanky for about 2-3 sec (no check engine light).
2. Idle smooths out and check engine light immediatly comes on.
3. I am noticing the knocking reoccuring but not near as strong as prior to teardown. Knocking sounds like it is coming from the rocker arms but I suppose could as easily be coming from cylinders
4. No smoke from exhaust.
5. I took an oil sample and oil is a bit cloudy but could that be from mixing with what was leftover in engine before teardown - IF there was still a fluid compromise I would figure it to be more substantial considering how much I have run engine after rebuild
What next - help please
Thanks
David
Yadda yadda
When starting, engine would begin knocking horribly after about 3-4 min and mucho white smoke would come from exhaust (burning antifreeze) Noticed water/antifreeze was mixing with oil on oil change (looked like melted chocolate icecream - very bad). Tore engine down to heads and noticed a compromise in the head gasket. Got heads rebuilt and replaced gaskets.
Now on engine start:
1. Engine idle wanky for about 2-3 sec (no check engine light).
2. Idle smooths out and check engine light immediatly comes on.
3. I am noticing the knocking reoccuring but not near as strong as prior to teardown. Knocking sounds like it is coming from the rocker arms but I suppose could as easily be coming from cylinders
4. No smoke from exhaust.
5. I took an oil sample and oil is a bit cloudy but could that be from mixing with what was leftover in engine before teardown - IF there was still a fluid compromise I would figure it to be more substantial considering how much I have run engine after rebuild
What next - help please
Thanks
David
taillight
08-20-2007, 08:41 AM
Pull the trouble codes and find out what the computer does not like.
tubadave
08-23-2007, 06:22 AM
I recieved a trouble code 13:
No change in MAP From start to run
No difference recognized between the engine MAP reading and the barometric (atmospheric) pressure reading at start-up (Chilton)
Aside from the check engine light coming on, would that have remotely anything to do with the knocking issues I am hearing?
Thanks,
David
No change in MAP From start to run
No difference recognized between the engine MAP reading and the barometric (atmospheric) pressure reading at start-up (Chilton)
Aside from the check engine light coming on, would that have remotely anything to do with the knocking issues I am hearing?
Thanks,
David
rhandwor
08-23-2007, 06:32 PM
All the anti freeze in the oil probably damaged a cam shaft bearing. You probably need to pull the short block and rebuild or buy an exchange unit.
Check compression in all cylinders as you should have bad compression if a cam bearing or rod bearing is bad. Use a gage and check oil pressure as a bad bearing will cause you to loose oil pressure.
Check compression in all cylinders as you should have bad compression if a cam bearing or rod bearing is bad. Use a gage and check oil pressure as a bad bearing will cause you to loose oil pressure.
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