The car has 120,000+ miles on it, but the engine was recently swapped for a low mileage engine (roughly 30,000 mi). The engine was NOT a crate engine, definitely a junkyard engine that had sat for a long time. AC and ps issues have cropped up due to dried up seals, indicating that the engine sat dry for a long time. That is probably a factor here
Here's what we have done, in order (I think):
- listened for any vac leaks, there is no obvious hissing. we haven't done a smoke test or anything yet, so that may be in order
- cleared mixture self-learn value (disconnected B1 MAF, started and ran for ~5s, stop, reconnect). when we did this, the O2S data went back to normal and learned back down to a lean condition
- swapped the O2 sensors across the banks. values were the same
- swapped MAFs across the banks. same values
- swapped injectors across the banks. same values
- briefly checked for exhaust leak. no obvious leak, but I definitely need to check more thoroughly
Here is what I've got for data:
This is a freeze frame, but the lambda values, fuel trims, and O2s data are all effectively the same from idle to medium load. If any other data will be helpful, I can upload it.
The engine shakes noticeably at idle sometimes, but multiple times a drive at stoplights and such. It misses badly enough that you can hear that its missing when standing outside the car. The issue has been consistently worsening over the past 2 or so months. When the code first cropped up, there was no missing and no shaking was happening at idle.
Additionally, there is a weird rattling sound, that we believe is unrelated. It sounds like either cat material rattling around or a belt drive pulley with a shot bearing. It isn't a consistent rattle and has worsened as well. Here's an audio recording of it:
https://limewire.com/d/UvpiE#Kb0JfdDcia
Also, the voltage gauge jumps around considerably, which it did not do before. It jumps around by about 0.1 V. The needle never sits still. Important to note here that we had to put in an Autozone remanned alternator in after the power steering fluid leaking from the pump housing due to a dried up gasket fried the one that was on it when we got the car back after the swap.
I plan on taking a good look at any potential exhaust leaks later this week (and will also do vacuum leak detection afterwards), but if the answer is obvious or if there's anything else I need to be trying that help would be greatly appreciated.
