This is my first post here. Thanks for a great board guys.
Recently, my ’95 Tahoe with 67K miles got a SES light that my dealer coded as a malfunctioning EGR valve, so at his suggestion to save me some bucks I cleaned it (soaked it in my gun cleaner Ballistol overnight), and put it back in only to have the SES light come on again 2000 miles later. I think my problem is that I “baby” my engine by keeping revs to a minimum, and with a lot of around town driving in overdrive, I’m assuming I get carbon buildup in the top end of my engine including that pesky EGR valve.
I was going to use a top end cleaning chemical to clean her up, but did a Google search first for ‘Top End Cleaning’ information, and found a Ford truck board where someone suggested running the engine up to at least 4000 RPM for a mile about once a week, and that method will clean the engine free and easy.
So off I went down the interstate REDLINED at 4000 RPM in 2nd gear (about 55 mph) for a mile and got off the next exit to go home. I kept the AC and radio off while redlining so I could listen for things coming apart, but only heard a tight engine and screaming tranny gears. During the redline mile my water temp gauge moved from 180 to 200 degrees.
Well, all I can say is that I don’t remember my 350 TBI running as smooth as it does now [img]images/graemlins/smile.gif[/img] No SES light coming on (at least not yet) and it idles smooth as silk at traffic lights (no more intermittent misfires). The hot gas cleaning method must work because I noticed the inside of my tailpipe is as clean as the outside where it used to have that black carbon coating, so I’m assuming the top end of my motor is just as clean.
Here is the link to the Ford board discussion of top end cleaning FYI.
What I probably should have done first, and will do next is find a Ford Expedition/F-150 to peek into and see if 4000 RPM is redline for that engine. If it isn’t, the next time I do this I’ll probably lower my RPM’s to 80-90% of redline rpm’s, because it seems to have cleaned up so quickly that I probably didn’t have to strain the motor and run the revs up so high.
Anyway, has anyone else here tried this top end cleaning method? I never heard of it before, but it made sense to me, and it appears to have worked great. Again, thanks for all the great info on this board.