Please bear in mind that its very hard to diagnose an issue with out being right there in front of the vehicle, but given the history and symptoms of the vehicle I would say yes, the vacuum leaks @ the intake will cause the IAC to act erratically as the PCM is trying to compensate for the additional "air" coming in (simplified) Second, the p0170's codes point me in that direction too as it indicates both banks are lean.
Having said that, there are also issues w/ the MAF causing p0170's codes and even if the MAF specs out ok. Additionally, there are also IAC issues too but they usually pop a code and its pretty obvious.
You need special equip to nail the diagnosis though, be able to graph the O2 on a scanner or labscope and some carb cleaner sprayed on the intake mating surfaces is my favorite quicky test for an intake seal test. Do it when its cold and spray the carb clean and "watch" the O2 go fixed rich and your pretty much done
I would have to recommend taking the vehicle to a trusted shop and get it diagnosed properly.
Anyone else out there got any good quicky tests? Hope this helps!
Wednesday, December 6th, 2006 AT 6:31 AM