Need help diagnosing CEL code #12 ----1 MIN VIDEO inside

[jwahl425]

I just installed a 91 turbo engine/tranny in my 93 laser 2.0 N/T I swapped the computers and ran 3 wires, one for the knock sensor from pin #9, one for the 7th maf wire from pin #3, and one for the FPR solenoid from pin #57, the CEL code says its the MAF sensor, what could be the problem? here's a link to a VIDEO I took of the problem, the CEL is intermittent:

http://media.putfile.com/Engine-diagnostic

 

[jwahl425]

does anyone have any idea?

 

[DanThMan1983]

Too bad ya dont have a logger to see what the MAF is seeing. Try rechecking your wiring.

 

[Auto RS T]

A logger would truly help you. It took me a long time to realize this.

I would also double check the connections, did you use solder and heat shrink?

Do you have another turbo mas to swap out?

I am curious to know why you had to run the FP solenoid wire?

 

[jwahl425]

A logger would truly help you. It took me a long time to realize this.

I would also double check the connections, did you use solder and heat shrink?

Do you have another turbo mas to swap out?

I am curious to know why you had to run the FP solenoid wire?

I swapped out everything, MAS, ECU Tranny, Engine and I like quicker startups so i wired in the FPR solenoid, Yeah, I used solder and heat shrink, a loger is my next thing after a Fuel Pump

 

[Auto RS T]

Check the mas sensor wires in the stock harness, you could have cut/broke or grounded one out in the install of the motor and transmission.

 

[jwahl425]

well, I spent 7 and a half hours re-soldering ALL of my connection from the ECU to the MAF plug, and the other wires I added in for the conversion, then I just cut off the plug and Soldered on another one I had, that didn't work. Is there any way that because my vacuum routing is off this could cause this code? I ordered a datalogger but it won't get here till next week the only other thing that could be wrong is that the MAF IS BAD, but I checked the resistance according to the Manual and everything checked out ok, does ANYONE have the wiring diagram for the MAF sensor? the car runs REALLY rich at idle, I don't have the downpipe hooked up so the gas fumes burn my eyes, maybe there is something else in the MAF circuit that is throwing the code. Oh, and the car will run normal, say I have 20% throttle then I floor it the car stutters for about 1 - 2 sec and then boost's normally. It's kinda wierd because it runs kinda crappy when the CEL is on but when it's off it runs FULL CRAPPY WTF it's only off for about 1 min then it comes back on.

just thought of this, I did accidentaly hook the Green/Orange wire to the green Yellow wire, could this of messes something up in the MAF?

the intake manifold has a LOUD whooshin sound coming from it, I checked all the hoses and everything seems ok, I listened close and it sound louder then I remember it normally being.

things I've tried:
searched for god knows how long
Resoldered ALL the connections that I made
Soldered on a new MAF plug
replaced ISC motor
Replaced sensor in front of the BISS screw
reset the ECU about 20 times
found/fixed 2 vacum leaks but they didn't do anything

 

[jwahl425]

Well I found the Wring Diagram located here:
http://www.dsmtuners.com/forums/showthread.php?t=48231
down the page a little

the wires run through the MPI control unit, where is this locate, I have my parts car right next to mine so I can just swap it and see if it works.

 

[Auto RS T]

Doesn't the 7th wire go to pin #6 on the ecu and not pin #3? According to my diagram pin #3 is for the turbo gauge and #6 is for the maf.

Double check this, also it looks like there is a wire that goes through the tps also from the maf. Check my first suggestion.

The MPI control unit is the ecu.

 

[jwahl425]

yeah, I already put it in pin 6 where it's supposed to be, that didn't do hardly anything. just after I posted I went out and changed the TPS sensor didn't do a thing, kinda funny we both thought of that, I pulled it off the engine I had before so I know it works.

 

[mavisky]

The extra maf wire runs to pin #6 on a 1991 and later car.

Turbo

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NT

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Sounds like something might be wrong with the maf itself, try to find someone else's you can borrow.

 

[jwahl425]

sounds like a good idea, I might try that, I had someone with better eyes then me look at the wires, I had the Green orange and Green Yellow wires crossed, but now half the time anything below 80% throttle the cars stutters, code still says MAF-Sensor, what could be wrong with it that it can't recognize normal throttle?

 

[jwahl425]

I can't find one and autozone wants 240 plus a core charge of 45, I am also throwing codes.

12 Volume air flow sensor
13 Intake air temperature sensor
14 Throttle position sensor
25 Barometric pressure sensor

the wierd thing is is that the CEL is intermittent is there an easier way to test the air flow sensor??

 

[mavisky]

That most definitely sounds like a bad maf as 12, 13, and 25 are all housed in the mas. The other is probably a mis-aligned or bad tps sensor.

Does anyone around you have a 1g maf you could try out? I'd send you mine to try, but I sold it last year after upgrading to the maft.

 

[sheldon]

You could just upgrade to a 2g maf for maybe 50.00 from the junk yard if you cant find a 1g maf...Thats what i payed for the maf and harness plug...then spend maybe 30 minutes soldering the new wires which are on vfaq

 

[jwahl425]

that sounds good I think I might get a 2g maf or GM w/translator but today I found out that my coolant temperature wires were bare and rubbing, The GREEN/BLUE and GREEN/RED wires run from the Mass air flow sensor to the TPS and Engine Coolant Temperature sensor

here's a pic:

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[jwahl425]

after I fixed the coolant temp wires the code went down to just the TPS and MAF sensor, the MAF sensor's signal voltage is right and so is the battery voltage, so why replace or try to change the MAF? I want to figure out the problem, if I borrow someone else's MAF-S and there is a short then I could mess their's up too, the TPS and MAF are connected by the green/blue and green/red wires, the green/blue also goes to the Coolant temp sensor, so what is the best way to test continuity for those two wires? also I have 3 TPS's and all three were rated at 4.1-4.4 closed and <.5 when fully open when it's supposed to be 5 cl and .9 open, all three can't be bad so maybe the throttle body? but I already cleaned that out, the harness for the TPS looks good too, If I get my datalogger I should just do a run and post up the results and you guys can tell me what's wrong? the payment for the datalogger should clear monday and I should get it <2 days after that so hopefully I can get it fixed soon.

 

[jwahl425]

You could just upgrade to a 2g maf for maybe 50.00 from the junk yard if you cant find a 1g maf...Thats what i payed for the maf and harness plug...then spend maybe 30 minutes soldering the new wires which are on vfaq

yeah but if I dd that I would lean out more then my N/T fuel pump can handle, my next step is a 190LPH pump, I'm not looking for more then 330HP, the 190 and small 16gw/FMIC will do that

I finally got sick of testing every wire in the d*** harness and since I can't find anyone with a sensor I started the car, now with the CEL on it stutters at 4k when floored, I pulled the #6 pin of the ECU and floored it, it did the same d*** thing as when it was plugged in, looks like I'll have to get the sensor I was looking at on ebay, does anyon know what the #7 maf harness even control? I see in the diagram above that it's some kind of resistor?

 

[tom04841]

Just a thought, but are you POSITIVE it isn't a 90 ecu? If it is, you mat need to swap pins 6 and 14.

 

[jwahl425]

how do I found out? it came out of a 91 with no check engine light so I don't think so, I switched the #6 and #14 and it idled fine but when you lightly or floor the throttle it feels like air goes in but no fuel, then after 2-3 sec of that it revs up to 7k w.no stutters like before at 4k. then while driving it feels like the MAF-S can't see 0 to 30% throttle, then afterthat it's fine though besides random stuttering.

this is pin #6:
Air flow sensor active filter reset (idle switch)
(switch with 6 if using a 91-94 ECU in a 90 or vvs)
Stock wire color - Green

pin #14:
Idle position switch
(switch with 14 if using a 91-94 ECU in a 90 or vvs)
Stock wire color - Green/White
7th wire from MAF-S during conversion

 

[jwahl425]

so I drove 2 1/2 hours to Norwalk Ohio today to borrow "Auto RS T"s Mass Air Flow Sensor, bolted it up, put it in, looked at the HZ on my friends DRBII and it still said 0HZ!!!!!!!!!!!!!! so we got to thinking it might be the ECU, I borrowed his E-PROM ECU started it up and checked the Readings, we have HZ!!!!, also, the bad ECU was causing the random misfire in some of the injectors, the TPS still needs adjusted but that's the only CEL I'm getting!! you guys should check out AUTO RS T's ride, it looks stock on the outside w/smic but he's runnin 750s! he's also puttin in a Supra Sidemount later on, it's going to be one sick sleeper!