Quote:
Originally Posted by Tonypepatone
Could this actually be there source of my problem?
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Oil on the spark plug threads? No, that isn't a big concern. If you see carbon tracking on the plug ceramic or frank oil on the coils, I'd start to worry. Regardless, I wouldn't necessarily suspect a lean condition from that.
High trims on low throttle while moving (semi-engine braking) is indicative of a vacuum leak, particularly if the trims are closer to normal on throttle. Have you checked the PCV and EGR systems? Using your OFT, I would check the "Boost" value at idle and I would check the MAF voltage on and off throttle. If those seem out, it might help point you in the right direction. Worst case scenario, I'd do the following:
1) Pull the MAF and clean it with an isopropyl alcohol-based cleaner, let dry completely
2) Pull the PCV valve and clean/replace it (they're stupid cheap and kind of a pain to clean). Check the hose from the PCV valve assembly to the intake manifold for damage.
3) Check the EGR return tube into the intake for damage. Trace it back to the engine and determine if it's loose (it's hard to see without pulling the manifold).
If nothing changes with all of that, find a friend with a smoke machine and go to town. Personally, I have found that the exhaust manifold gaskets are susceptible to serious corrosion in the cold north where I live. I just finished tracing my own issues with high trims and it led me to completely corroded manifold gaskets which didn't even sound like they were leaking. Replaced those and my trims improved by >10%.
Edit: After reading the past posts more carefully, I see you said there was oil on the outside of the electrical connectors to the coil packs? That sounds like you have an oil leak, possibly coming off of the timing cover at the head or one of the camshaft sensor plates. There is a TSB for this. I have this same issue - my oil leak is not terrible and I think it's coming from the timing cover (instead of just the cam cover bolt/s), making this job an enormous pain. I'm waiting until I see oil on the ground to mess with it.