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197 Views 1 Reply 2 Participants Last post by  davester
I just got my truck back yesterday, rebuilt LH-6 5.3 liter. No going over 3000 rpm for the first 500 miles, typical...First drive I noticed a surge when on cruise, especially when going up a slight hill. I figured it was a lean condition, based on a google search. Called my mechanic and he said if there wasn't a code that popped up there wasn't anything to diagnose. It is very evident that there is a problem, what are your thoughts? It will be going back on Monday...just thought I'd check with everyone on here first...Thanks, JD
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743 Posts
could be a minor intake or exhaust leak, or a fuel pressure problem. You can diagnose stuff without codes, it's just less straightforwrd. The engine can be running like crap and still not throw a code, depending on what the problem is.
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