Major maf, mass problems

[kchaazz]

So, i put a new engine in the car, removed cruise, air conditioning, power steering, and relocated bat to trunk. Get car running, but it doesnt idle for crap. Logger says its the mass and ive got a cel, but the thing is, when i hit the throttle the cel goes off. During the time the cel is on, logger says im reading 0.00 hz from the mass but when i hit the throttle, itll read air until it settles to idle again. car is running like crud too, barely wanting to idle at all and i havent tried to drive it yet. what is wrong? please help me im at a loss here.

 

[sergiosdsm]

try swapping a mas from someone elses car and see what happens

 

[FORMONTOYA]

The idling situation sounds like when I once forgot to hook up the MAS. I agree, find a buddy with one to swap if you can.

 

[kchaazz]

Yeah, sorry i was in a hurry when i first posted. Actually, i already tried 3 known good mass units, and also another known good ecu as well. Also, i have the ac removed along with the related hoses and power steering removed and cruise removed as well. Is having those 3 things unplugged somehow screwing with my electrical system? Ive tried even taking the safc 2 out of the equation and it didnt help. This is really driving me nuts, the car actually idles better with no mass plugged in!! Like i said, the cel goes off as soon as i touch the throttle and the mass also reads air but its like as soon as the throttle slaps shut and the rpms go down to 800 or so, the mass just shuts off and reads 0 air and the cel pops right back on. Im at a complete loss as its not my mass and not the computer either. Also, a vaccuum leak is unlikely as im pulling 22 inches at idle, and a leak in the intercooler and piping is ruled out as i hooked the intake pipe with mass directly to my throttle body elbow with the same results! Also, fuel pressure is set perfectly and timing at 5 deg with the ecu grounded and new 6es plugs and wires, new fuel filter, all installed with my new motor and everything is plugged in as well. I also swapped throttle bodies so its not likely to be my tps, isc, or that "throttle closed" switch

 

[steve]

Time to sit down with the multimeter and make sure that the harness wiring is correct and working. It sounds almost like you have the IPS switch connected to the MAF reset.

Steve

 

[kchaazz]

Thanks a lot for the help!! So, where is the maf reset? Unfortunately, the electrical part of my dsm is something im not too terribly familiar with

 

[steve]

MAF reset is a wire from the ECU to the MAF pin 1.

You'll need the wiring diagrams (and for a '90 those will be fun to come by) and you'll have to trace out the various harness to make sure nothing is crushed, crossed or shorted.
http://www.ecanfix.com/~mdhamilton/1990schematics.html

Another potential issue could be a mismatch between the car and ECU since two pins on the harness switched between 90 and the later years. What ECU are you using?
The pins that are swapped between the two are MAF reset and IPS.

Steve

 

[kchaazz]

The ecu is actually the one that came with my car and ive had the caps replaced a while ago and visually, the ecu board is in exeptional condition in comparison to others ive seen. Also, the ecu i tried was from my friends 90 and it was remanufactured and in good shape as well. I just dont get it.

 

[kchaazz]

Ok, update, apparently the auto parts store gave me the wrong throttle body to intake manifold gasket, and it caused a massive vacuum leak. i made my own gasket, installed it, problem solved!! I just cant believe it caused so much trouble. Thanks for all the help, guys.