Vehicle : 04 Monterey, 180,000 miles


Problem : Vehicle stumbles and eventually stalls out once vehicle gets to operating temp. Typically, it will run fine, then the fan will kick on, idle raises a bit as normal, fan then cuts off, and immediately after fan cuts off, vehicle begins to stall.


Diagnosis so far : Checked fuel filter, air filter, cleaned maf, checked ecu for moisture, checked and cleaned tps, reset ecu, changed out b2s2 o2 sensor.


Noticed this issue about 2 weeks after o2 sensor went out. Replaced 02 sensor about 3-4 weeks after CEL popped on. So basically 4 weeks (400 miles) on a bad o2 sensor.


The car runs perfectly fine when applying throttle and driving, except for a "dead spot" at 1800-2000 RPM under light load (had this for over a year). The idling issue does not happen every time, but it is starting to get worse.


Ideas?

 

I would check the proper operation of the IAC or replace it. At 180K miles I would imagine that the shaft has some wear that may be affecting it operation. I just replaced mine at about 153K miles for stalling issues. Your 1800-2000 RPM dead spot may be your TPS.