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SDSU Alumnus
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Good job taking the time to snap all of those parameters. With Barometer essential "dead" you will want to at least test the MAFS connector. I would want to verify the +5v on pin #1; ground will be black on pin #5. Procedure to test MAF w/ Multimeter???/// and diagram

Even with the car warming up (cold temp reading), it is curious to see the narrowband o2 reading at 0.02v. Does this value cycle or oscillate? Does the car run any better while cold (open-loop) until warm (closed-loop)?
 

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Discussion Starter #22
Yeah I pulled the tape back on those wires and changed the plug just in case.
 

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How EXACTLY did you change the plug?

The connector on the MAS/MAF, from what I recall, does not readily allow wire removal and replace.
Is it possible that one or more wires are not all the way seated?
Possible that you swapped positions with 2 or more wires?

Did you check for +5 and ground on the pins mentioned above?

Bob.
 

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Discussion Starter #24
I changed the whole plug and wires together with another wiring harness I had that i just pulled out of another 3k and i know that one was good which is why i used it. The 02 is kind of hard to explain idk much about what it's supposed to show but last night it was going from .02 to .04 the other day I saw it at .08.

Now i just changed the injectors with the two from my other tt that i know are good and it's doing something odd.. I can pull the two injector plugs from 5 and 3 and literally still no change but its idling awfully high. Around 3k rpms. I unplugged the iac and plugged it back in and absolutely no change what so ever so I'm in the middle of swapping that out right now. The idle screw on the TB is down as far as itll go and idk what else controls idle.
 

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i would suggest checking for continuity from maf plug to ecu plugs and also check for cross feeding the ecu is either not receiving a signal or it is not processing it
 

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Discussion Starter #26
Changed the iac and idle is now fluctuating between 1800 and 2000 I'm testing the plug connector now
 

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Discussion Starter #27
These are the results of the maf plug readings. I first tested pin 5 which is ground if I'm not mistaken and as you can see it has 5 volts which I'm pretty sure it shouldnt because it's a ground lol I also tested it in ohms and it shows a 1 idk what that means at all
 

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Discussion Starter #28
I also just checked the ohms on the ground wire for the maf inside the car in the floor board with he metal plate that covers the harness. I pull the wire out of there and tested the ohms and it still shows 1 but its doesn't show the 5v when I put it on volts to see what it would do.
 

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In order to check voltage (or ground), you need to have:

A) If yu are checking for voltage, the meter set for Volts DC. Then the positive lead on the test wire and the negative (black lead) on a good body ground.
B) If you are checking for a good ground (continuity) you need to have one lead on the test wire, and the other on a good body ground, and the meter set for Ohms or Continuity.

Just trying to help.

Bob.
 

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Normally YES, unless you have a bad battery connection (to the battery or to chassis ground).
This does NOT sound like your issue, just putting this out to others reading this..
If you're unsure, pick an unpainted bolt or nut on the FRAME.
In the engine compartment, the strut bolts work for me...

Bob.
 

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Discussion Starter #32
So as I mentioned I was getting the "1" on the multimeter when testing the ground for continuity and from my online search that ment that the resistance was too high so I tried it on other settings and it was all just giving me the "1" so I cut the ground wire in half on the maf plug and tested it and on the 200 setting on ohms it gave me a solid 25.0 ohms so I attached a wire to each cut wire for the maf and ran it to the ground on the battery still didn't help my issue but i was just seeing if it would work but what was really interesting to me was I took the ground cable off of the battery and when I touched the ground wire from the maf to the negative post I got full power to the car not sure if that's normal or not but worth a note
 

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I changed the whole plug and wires together with another wiring harness I had that i just pulled out of another 3k and i know that one was good which is why i used it. The 02 is kind of hard to explain idk much about what it's supposed to show but last night it was going from .02 to .04 the other day I saw it at .08.

Now i just changed the injectors with the two from my other tt that i know are good and it's doing something odd.. I can pull the two injector plugs from 5 and 3 and literally still no change but its idling awfully high. Around 3k rpms. I unplugged the iac and plugged it back in and absolutely no change what so ever so I'm in the middle of swapping that out right now. The idle screw on the TB is down as far as itll go and idk what else controls idle.
NBO2 voltage should be cycling from 0 to 1 V when the car is warmed up, indicated closed loop fueling. If your O2 voltage is "stuck" near 0 even after the car is warmed up, is can be a failing/bad O2. Same thing happened on my rear O2 and it would prevent closed loop fueling.

Also, high idle might suggest a vacuum leak, not sure if you checked that yet.
 

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NBO2 voltage should be cycling from 0 to 1 V when the car is warmed up, indicated closed loop fueling. If your O2 voltage is "stuck" near 0 even after the car is warmed up, is can be a failing/bad O2. Same thing happened on my rear O2 and it would prevent closed loop fueling.

Note that 3 and 5 are fired by the same coil i believe. No change when pulling either of those injectors could also point to coil/PTU issue. Just a thought.

Also, high idle might suggest a vacuum leak, not sure if you checked that yet.
Paired coils are 1-4, 2-5, 3-6
 

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Discussion Starter #36
We finally figured out what was the problem (note we bought this car the way it is) after figuring out which wire was for the barometric pressure sensor (orange on the maf plug) I traced it down to the ecu and found that there was a quick connect clip on the wire and it there was no bare wire to make contact. Needless to say I fixed that issue, but now I have a way bigger issue. The idle has come down back to 800ish. It doesn't sputter like it did, but now its cutting out itll idle fine for about a minute then out of no way it starts cutting out and acting like it wants to turn off and of course I have no check engine light to tell me what the problem is so now I dont even know where to start. If yall would like for me to start a new thread that's fine I'd like to continue it so yall know what has been going on though.
 

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Well, now that you know the previous owner had "something" tied into the ECU wiring, have you started checking ALL the wires at least at the ECU end to make sure there aren't any other "half assed" removal of splices?

I've only run stock ECU's (no add ons), so maybe someone can give you a clue what add on may have been tied into the Baro signal. Maybe that will give you more info about what other wires may have been spliced (compromised).

Sounds like a mess. Sorry.

Bob.
 

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We finally figured out what was the problem (note we bought this car the way it is) after figuring out which wire was for the barometric pressure sensor (orange on the maf plug) I traced it down to the ecu and found that there was a quick connect clip on the wire and it there was no bare wire to make contact. Needless to say I fixed that issue, but now I have a way bigger issue. The idle has come down back to 800ish. It doesn't sputter like it did, but now its cutting out itll idle fine for about a minute then out of no way it starts cutting out and acting like it wants to turn off and of course I have no check engine light to tell me what the problem is so now I dont even know where to start. If yall would like for me to start a new thread that's fine I'd like to continue it so yall know what has been going on though.
Is this temperature dependent at all or does it just randomly happen whether the car is warmed up or cold?
 

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Discussion Starter #40
The plug looked worse than it actually was. That was the only plug that had another tampered with on the ecu itself. We found another hack job at the dimmer switch it looked like 2 other wires soldered onto one of the wire but they were both cut off. I cut all of that out and replaced it with a switch harness from a parts car and now I have dash lights. ( didn't have them before figured it was the switch itself turned out to be wiring) also my headlights dont work but that's a whole different mystery. As for the idling being temperature dependent it is not. Once I start it itll run really good for about 5 seconds and then start to cut out. I was watching the rpms on the scanmaster because it's either to pin point the number of rpms. When it does it, itll drop down to almost 500 rpms then jump up to around 1700 then back down to 800 then it just repeats after about a second, and just repeats. I held the throttle down to 1800 rpms and she purs. No cut outs no sputtering, it runs perfectly fine. I haven't driven it down the road yet because it has no brake rotors so idk how it acts why driving it.

Early I pulled the intake, valve covers and injectors out. I swapped the rear injectors with the front because I know the front three are good, so I'm going to test the replaced fronts tomorrow. All the valve springs and rocker arms seem to be in solid condition. The oil smells really strong with a gas smell. Burning my eyes strong. It's still burning really rich.

I posted my scanmaster data in an earlier comment and all the readings are still the same with the except of being 2 or 3 numbers off on 1 or 2 different readings, except the bar that is now reading at 97 which I imagine is good lol.
 
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