Gm Engine Clean

[theintimidator3]

OK so in one of my posts I was asking about my truck pinging.
Some people have sugested using a cleaning agent for the engine. If someone really knows the use and what it actually cleans let me know. When I bought my truck last year, the first thing I did was go out and bought GM ENGINE CLEAN. Now I thought it was supposed to clean the entire engine out????? Am I wrong??? According to one of the posts, it doesn't clean the upper chamber. This stuff I bought was put into the crankcase for 10 minutes then the oil was changed. It looked like pink diesel fuel.

Joe
1986 GMC C1500 Stepside
305 4BBL
Still stock for now

[KShortell]

What you wanted was GM's Top End Cleaner. This is run down the intake. You do need to disconnect the AIR (Air Injection Reaction) solenoid on the system if you have AIR. It's also adviseable to change your motor oil afterward.

I used a can of it from my local GM dealer a couple of years ago. I can't say that it was a night and day difference, but it helped a wee bit.

If it's any consolation, my truck's 350 has liked 89 octane ever since I bought it. It'll run OK on 87 and is rated for 87, but it's always had a slight spark knock at part throttle on the Interstate at speed. 89 helps.

Good luck!