I have on my hands a very confusing problem that i am now getting back around to playing with... (I turned into a complete traitor and bought an 08 dodge 3500 6spd manual w/ exhaust brake that just really turns my crank )

Anyways, last year i 3.4 swapped my 94 extracab with a motor from a 2001 tundra. Both trucks manual trans, running 2001 Tundra M/T ECM (hard to find!) and was all linked together with ORS wiring harness. In addition, has 2nd gen TRD Supercharger, URD's 6 injector kit with Supra 7mge injectors (318ccc i think), I put the Wahlbro 255 pump in the tank, full custom headers with 1 1/2" primaries with a 3-2-1 combination before the crossover, and a 2-1 dump to run out to muffler.

I have the stock A/f sensor, the stock o2 sensor, as well as a 3rd (A/F) sensor that is tied to the AFR gauge on the pillar inside cab. also have a boost gauge hooked up to monitor as well.

The truck is lifted 4" suspension, 3" body, 35x12.5x15 bighorn maxxis tires, detroit locker in the rear and truck has been re-geared to 4.88s, and is 5spd.

Now that you know what i'm working with, here is my problem: The truck makes excellent power, in my opinion, accelerates smoothly all the way thru the power band with no hint of dead spots as some of the other guys have mention with being S/C'd. Where i have trouble is maintaining a constant speed, ie driving through town, or on the highway. Any gear, any speed, no matter what, if i am trying to maintain, as in just hold a steady speed, the ECM starts searching high and low (or rich and lean if you will) for the proper AFR. I watch it on the AFR gauge, it runs too rich for a couple seconds then it will lean way out, then run too rich again, then lean way out. When it does this the whole truck shudders and bucks like a friggin bull at the rodeo, and you can only solve it by mashing the pedal to the floor.

Ive replace the TPS twice, first one failed, threw a code, second one was defective out of the box. just my luck! The only two codes i have through all of this are for the evap system because i never plumbed in the 3.4 evap canister and all that crap. I have the 3.0 canister in place still.

I've tried to change the tuning following Gadget's u-tune, spent hours tuning to no avail. Fuel trims stay within spec, nothing seems to ever make any sense. No mechanic in town will touch it. TRD's rep at a toyota dealer in the big city said I should have gone with URD's 7th injector instead of the 6 to begin with.

I'm looking for help, thoughts, ideas, questions, ANYTHING at this point is a plus! I threw $15k at this truck last year, and now it sits idle and hasnt been driven for 4 months or so, I hate to see it rust away out here on the Oregon Coast.

 

What pulley, how much boost? You really ought to cross post this in the 95.5-04 section too.

 

stock supercharger pulley, and forgive me for saying something stupid but I haven't adjusted or changed the boost at all. I have a boost gauge hooked up, and it makes anywhere from 0-8 lbs when i'm driving, dependent on how heavy the ole right foot is.

As far as cross posting, that's outside my technical ability

 

Right on, I'm just saying you might should start a new thread over in that section. You might receive more help and more quickly.