Big2dabank
Well-Known Member
- Messages
- 1,216
- Location
- Central Florida
Hopefully someone else has experienced this problem. I have a 2005 H2 SUT with 200,000 miles and over the past couple of months, I have noticed that there is slight hesitation on acceleration and the idle is very rough once the engine is hot or has been running for more than 30 mins. It feels almost like a misfire, but the DIC is not showing and codes and had a diagnostic done yesterday and it did not show any codes, and all sensors (i.e., O2, knock, etc.) were showing fine. The technician I spoke with is someone I trust and is a personal friend, he told me that it is most likely the timing chain, which may have stretched slightly and when the engine is cold the chain is tight enough not to notice the problem, but once the chain gets hot, it is possible that even some minor expansion could cause enough slack in the chain to throw of the timing. It seem logical, but I wanted to see if anyone had any other ideas before I go this route. For starters he suggested I put a wrench on the drive fan and try to turn the crank shaft to see if there is any noticeable movement or play when the engine is cold and to try this again when the engine is hot to see if it develops any play in the chain. Any thoughts you guys may have would be appreciated.