IACV Oversensitive or Underlying Design Fault
On 1/09/2012 daughter breaks down in Maxima and I go to fetch her and "it" hopefully. Cold starts fine and idles at 7-750 and I am thinking a bad batch of fuel. Until "it" warms up and the throttle commences to surge on warmup while running up the Stevenson at 12am and it doesn't like 2000rpm at all. Drives better over 2k than under 2k and at idle "it" is high at 1500rpm. These symptoms remain...Cold start and idle are in spec ...until "it" warms up...Surging (2-3K) at idle and running and when not surging a high idle of 1500. There are 2 codes for the dreaded P0505 and thi8s cannot be...
1. This is a 2001 A/T GLE and "it" eats IACV! In Fall of last year "it" ate another IACV and an ECM and I documented the repair under the thread ECU Fried In Seconds post and finalized with a Coolant Bypass of the IACV. It cannot be the IACV at fault it is now bullet proof...with the repairs I made.
2. I run through the litany of EC faults in my head and decide to do an Idle Relearn. I do it several times NG.
3. Break out TunerMax's checklist and start going through it and I am testing the IACV and each of the 6 pins are between 21-24ohms. Note I did not check CONTINUITY!
4. Decide to retune the TSP by using the .05 & .15mm gap at cable and multimeter at lower set of pins. Finally get it done. TSP relearn done. Same symptoms remain and I pull the IACV out again and check the pins which all test within spec. But this time I check CONTINUITY AND PIN NUMBER 4 MAKES A SLIGHTLY DIFFERENT SOUND! Note the ohms are all in spec at 21-24ohms.
5. Return it to AZone check the new one in the store for resistance and continuity and reinstall it with TSP retune and it purrs very nicely. Maybe 6 hours of actual frustration to correct it back to normal. What is there in this design that has such little tolerance for error? Sorry just a little rant!