Need help with CEL and PCM issues 98 GT 91,000 miles on the odometer. These are basically notes to myself: Would like your comments/suggestions. Check engine light comes on after 20 minutes of driving after reconnecting battery. Rough running at Idle and at cruise speeds (closed loop) Codes: P0172 Bank 1 Rich - Passenger (Right) P0174 Bank 2 Lean - Drivers Side (left) The main thing IÃ¢â‚¬â„¢m going to do right now is to drive it carefully for a few more complete cycles in hopes that the PCM will adapt to the new air flow. Will NOT be disconnecting battery to reset computer. What IÃ¢â‚¬â„¢ve done so far or intend to do: Listen carefully for detonation. Result: NO DETONATION DISCERNABLE. Determine if it runs OK in open loop Idles OK ?? throttle response ok ?? result: SEEMS TO RUN OK IN OPEN LOOP 2 Possible vacuum air leak left side causing computer to throw left bank lean code and enrich mixture thereby making right bank throw rich code,. Check for vacuum leaks especially around left side of intake manifold, injectors. - doubtful because IÃ¢â‚¬â„¢m pretty sure it was installed correctly. Spray some carb cleaner around potential vacuum leak areas. Result: NO DISCERNABLE LEAKS 3 Clean the MAF with contact cleaner. Possible but unlikely. DO THIS SOON 4 Check temp sensor, the one that sends data to the pcm Ã¢â‚¬â€œ probe voltage Remove the Teflon thread wrap from sensor threads. 5 Check air temp sensor in the CAI Ã¢â‚¬â€œ disconnect it Ã¢â‚¬â€œ probe voltage - doubtful 6 Take out the 180 degree thermostat and replace with stock one. Doubtful. 7 Remove the IAC restrictor. Doubtful since it runs rough under power. Result: NO EFFECT OTHER THAN GETTING THE RPM HANG BACK. 8 Swap the right and left O2 sensors. See if lean/rich codes switch from left to right. DO THIS AFTER I DRIVE IT FOR A FEW MORE COMPLETE CYCLES 9 Replace both 02 sensors ? Doubtful, to much of a coincidence for one to go bad just now. No code indicating bad o2. they seem to be working. 10 Drive it easy for a few more complete cycles. See if the PCM adapts. 11 Intake manifold installed wrong ? I donÃ¢â‚¬â„¢t think so. Pull it off and install it again ? LAST RESORT 12 One or both of the cams installed out of time ? DonÃ¢â‚¬â„¢t think so. Very doubtful. How would that throw rich/lean codes anyway ? Pull cover and chains, check cam timing. VERY LAST RESORT I know I'm probably making a big deal out of nothing, but i didn't expect the CEL or crappy running after the intake/cam swap. Any thoughts or suggestions would be great. I know there is a lot of knowledge on this subject out there. Thanks guys.