GM Top Engine Cleaner....solve knocking?
05-07-2006, 09:06 PM
#1
GM Top Engine Cleaner....solve knocking? I just changed my plugs at 50,000 miles after hours of labor (I hate you plug 8).
Anyways, I'm trying to just do basic maintainance on the car, and all has gone well so far, but I'm still unable to ditch the knocking I get sometimes.
When I go WOT, I get a rapid clicking noise which I believe to be knocking, around 4,500 to 5,500 rpm range. I run 93 octane gas. When I slowly accelerate, but don't shift and just let the car run up to 5,000 rpm or whatnot, it doesn't knock. It only seems to do this when I floor it.
I've heard of the whole oil getting into the intake and such problem, and heard that it has been known to cause knocking. I need to solve this crap asap and get my engine running nicely again. I bought some liquid "GM Top Engine Cleaner" from the local Chevy dealership. I'm about to run it through, but I've heard that doing this can cause crap to go all over, and will cause me to need to change my spark plugs and oil once more. I'm hesitating, as within the past few weeks both of these have been changed, and I'd be pretty pissed to have to change both the plugs and the oil again in order to eliminate this knocking noise.
Any suggestions on how to troubleshoot this knock, and opinions of the whole Top Engine Cleaner would be appreciated.
Thanks,
Rich
Anyways, I'm trying to just do basic maintainance on the car, and all has gone well so far, but I'm still unable to ditch the knocking I get sometimes.
When I go WOT, I get a rapid clicking noise which I believe to be knocking, around 4,500 to 5,500 rpm range. I run 93 octane gas. When I slowly accelerate, but don't shift and just let the car run up to 5,000 rpm or whatnot, it doesn't knock. It only seems to do this when I floor it.
I've heard of the whole oil getting into the intake and such problem, and heard that it has been known to cause knocking. I need to solve this crap asap and get my engine running nicely again. I bought some liquid "GM Top Engine Cleaner" from the local Chevy dealership. I'm about to run it through, but I've heard that doing this can cause crap to go all over, and will cause me to need to change my spark plugs and oil once more. I'm hesitating, as within the past few weeks both of these have been changed, and I'd be pretty pissed to have to change both the plugs and the oil again in order to eliminate this knocking noise.
Any suggestions on how to troubleshoot this knock, and opinions of the whole Top Engine Cleaner would be appreciated.
Thanks,
Rich
05-07-2006, 10:10 PM
#2
If you have carbon buildup on the heads and intake it will knock. Carbon holds excess heat and actually fires off the mix before the plug can, Top engine cleaner usually takes care of that. What I do (I'm a GM Tech BTW) is pour about 2 cups worth into the intake, crank it over one once or twice, Dont let it start, that gets the cleaner into the cylinders, let it sit for 3-4 minutes, then start the car ( it will probably be a bitch) Go run the crap out of it to clean all that junk out, then come back and do it again until you run out of cleaner. If you do it in steps like this I dont see the need to change oil or plugs. I never have. Also another method, spraying water into the intake, I know your thinking I'm crazy. Get a little spray bottle, put some water in it. Pull off the intake hose at the throttle body ( dont spray through the maf) start the car it may want to stall, but should stay running, crack the throttle to about 2K rpms, hold it there, give it a spray about every 5-6 seconds. This actually steam cleans the internals and gets rid of carbon. Do that for a few minutes then go drive it. It actually works, I was pretty skeptical at first too. Try those 2 things that should decarbon it pretty good if thats where the knock is coming from. If I can help anymore, PM me
