I'm getting a CEL and trouble code P1102 (MAF sensor in range but lower than expected) and I can't seem to track down the problem. I changed my oil cooler and when I was done I started getting P1102. I also got this code briefly when I first bought the truck about four months ago, I cleared it, and it never reappeared until after the oil cooler. Now it wont go away. I'll give the history of the work I did after describing what I have done to try to diagnose the code. First I cleaned the sensor with electrical contact cleaner, no change. Next I tested the harness for voltage. I didn't know what I was looking for, but found between .4 and 13.2 volts accross the 6 leads to the sensor at idle. I probably should have checked resistance or continuity for the sensor itself, but that's all over my head. I did check the six leads from the sensor for voltage while at idle and found Zero. I have a Dashboss monitoring system and it has two MAF related PIDs, one for voltage and one for flow in either grams per second or pounds per minuite. Both PIDs are reading zero under power at all speeds. I replaced the MAF sensor with one from a salvage yard (after cleaning it with electrical contact cleaner) and no change.
I'm having no driveability issues, except for sputtering for a few seconds when the car if first started. (I did a FICM rebuild a few months ago and my voltage is in range).
What do I do next??
The history I promised mostly in order of occurrence:
The truck has no CAT
I did the zoodad mod to open up airflow prior to the air filter when I first got the truck, no problem for a few thousand miles until I changed the oil cooler
CCV reroute to route crank case gases to a canister and then back to intake
FICM rebuild solved driveablility problem
High ECT vs. EOT led to a coolant flush. Did reverse flush, restore, then restore plus and filled with Zerex ELC CAT1
Still high deltas so new oil cooler and bulletproof egr cooler (I have smog in California) My temperature deltas are much improved, but still a disappointing 10 degrees.
Terrible drivability after oil cooler change until I purged air by driving WOT on freeway for a few minutes
Cleaned EGR valve manually (rags and q-tips) but did not use any solvent
Cleaned intake with a pressure washer
Added fuel pressure gauge
Put BB behind fuel spring to increase pressure (similar to blue spring mod). Fuel pressure climbed to 67 at freeway speeds
Wasted IPR during oil cooler change and had to replace
Cleaned & serviced Turbo while out
Had Turbo in and out 3 times (oil cooler, fouled up connection at EGR to exhaust, then for IPR) got pretty good at it
Tuned with SCT tuner that has canned tunes. Using canned tune Performance mode with high idle, and EGR off. Don't think I had an MPG gain, but throttle response, lag, and shifting are all significantly improved. Had trouble code before and after I started using tuner.
I think that's everything. Hopefully someone can help me out.