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OK so I've spent some decent time so far and can't figure it out. I put a new CME 4.7 stroker in my truck in September. After break in it ran great and so I went on a long planned road trip while towing a small travel trailer. Things went great after a few hiccups (hose from TB to map sensor popped out, harmonic balancer that I stupidly didn't replace when doing the motor seperated, clutch master failed) but after 3000 or 4000 miles I started to notice a pinging. I have an REM and saw my knock going up. Checked the sensor and the terminal was cracked so I replaced that (torqued properly and everything) but no change. It steadily got worse. I noticed my LTFT and STFT were both high. My LTFT is what I assume is the max of 166 because it's stuck there and STFT is between 100-170 driving and as high as 220 at idle. Most of the time so I'm very lean, causing the ping. My idle is also high most of the time, but not always suspiciously. Now here's where I thought I had it. Checked my manifold bolts and found one loose on the under side. Tightened it but no change. Just finished spraying all areas it could leak with TB cleaner to see the change in idle and I get nothing. Will try it again later with water as I know this will cause more of a noticeable stumble than TB cleaner. While doing the spray test I pulled off every vacuum hose and plugged the port with my finger to see if the idle dropped to normal indicating the problem was on that circuit but no luck. Also watched the REM at this time to see if the STFT took a dive. No luck on all counts. So it seems very likely that this is an installation error problem since I just had the motor out but keep in mind it wasn't immediate. I have larger injectors (forget which ones but I can look it up if important) but the problem wasn't here initially and grew worse over time so unlikely that's the issue. My o2 readings still switch but hang on the lean side more as you would expect. Everything else seems good and much is new with the engine swap. My last thought it that the bolt that loosened up allowed the gasket to blow out under if after hundreds of miles of not being torqued but as it's only vacuum I find that unlikely. It's also really hard to get in some of the spots where the manifold meets the block with a spray bottle. So that's where I am. I know how bad pinging and running lean is for a motor so I'm babying it and trying to get this solved ASAP. I have many (not all) of cruisers tips done if that makes a difference. Any constructive input is appreciated. Also, I'm on the road a bit so apologies in advance for possible sporadic responses.