I have a few ??? about the resister thing.... What happens if run with out it? is it needed? how much gain in power and milleage is seen... Im driving a 94 4x4 crew cab with the five speed.

OBD I, I think faults at 1st fire with it missing and sets a code, OBD-II faults at TDC offset you can run for a while with it out, but may quit at any time PCM thinks it need to self teach then is just cranks and engine won't start.

so is there a way to know what i have with out pulling the pmd?

i have been told that if it is not there it defaults to as if it had a #1 resistor in it

I am going to order a pmd cooler and want to know if I need to order the resitor or if i all ready have a #9 .... did they come stock or was # 5 the biggest stock?

i replaced my 5 with a 9 and didnt really notice any differnce in power or mileage, i think theres also a 13 out there somewhere

A #5 is middle of the road for 0 mm3/stroke as you increase to a #6=+1 mm3/stroke more, as numbers go up or-1mm3 going down.

Going up in #, 5 to 9 theoretically gains 4mm, I have heard but don't know for sure above #9 causes problems and sets code, 13 is biggest cal resistor. This is a calibration resistor, for matching IP to FSD/PMD really supposed to be flow matched at time IP is set up. I think this relationship is described in TDG IP how it works in FAQ section, guess I need to reread what is in there myself.

Same for me 5 to 9 no real seat of pant difference maybe on a dyno I'd see number change worth noting

In addition to replacing the resistor, you have to tell the PCM to relearn the new resistor value. 96+ Do this on their own, 94/95 I think will relearn with the same procedure as TDC Offset relearn...not 100% on that.
A Tech II will display resistor value on any 6.5, and IIRC it does have a command to relearn it.
Going from a 5 to a 9 is an appreciable difference, 4~5mm(3). Don't waste your money on the 13, they don't work, just set a code.

i never did any relearn procedure, will it learn it after a few start stop cycles?

In addition to replacing the resistor, you have to tell the PCM to relearn the new resistor value. 96+ Do this on their own, .
This one I'm still "wrasslin" with why, I know of 4 PCM swap where self learn did not happen of either resistor or TDC offset, I'd be willing to bet MDT will agree after wasting money on steak sauces "variable fuel controller" self learn resistor value doesn't happen always.

i never did any relearn procedure, will it learn it after a few start stop cycles?
According to my 98 GM manual and TDG once ECT gets to 170*F self learn is supposed to happn, never has on my truck, still stuggling on the why, OBD-I may werk differnt:(

acording to a paper thati got from stanadyne with a #9 resistor it can take up to 50 key starts to re learn the new resistor value and from a #6to #9 is supost to be a 6% increase in fuel delivery

so woudl you say that it is worth the money to order a #9??? Did any of your trucks come stock with a 9

Its a cheap easy mod, and does offer noticeable gains. If you do purchase one, I reccomend visiting a dealership and having them relearn the resistor value with a Tech II, or if you can find another shop with a Tech II they might be cheaper, Snap-On and similair scanner won't do it.

i do not have one in my trucks i don't own a vehicle that even has a computer in it i did one for a friend apr 1 05 and he has not noticed any diffrence but it has only been 1 day mabey started 5 times