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I managed to get the AC fan rewired up (safely) and it also spins with the cooling fan when I first turn key so that's a plus (I think).
Sort of, but no fan should run by just turning key on. There’s still something wrong with that setup, might keep engine cool but it will make getting heat in cold months a lot harder.

and checking the injectors resistance with my multimeter but can't seem to a how to to check resistance of those on here
You can check front injectors by just unplugging them and reading between two pins of each injector. To read back injectors without pulling plenum follow this post from Steve ’93ES.

 

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LOL! I was just going to look that post up!
Seems like it was only yesterday we were breaking in the new guy......;)

FWIW I would check the ISC FIRST. (Idle Speed Controller, sometimes called the IAC Idle Air Controller)
A failed ISC can damage the ECU so testing that and at least unplugging it if it's bad, would be my priority.
Besides, it's pretty easy to do. Just unplug it and ohm out the pins.
 

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Discussion Starter #143
LOL! I was just going to look that post up!
Seems like it was only yesterday we were breaking in the new guy......;)

FWIW I would check the ISC FIRST. (Idle Speed Controller, sometimes called the IAC Idle Air Controller)
A failed ISC can damage the ECU so testing that and at least unplugging it if it's bad, would be my priority.
Besides, it's pretty easy to do. Just unplug it and ohm out the pins.
Thanks I'll do that first! Where exactly can I find the ISC, also where the hell is the ECU?
 

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Discussion Starter #145

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Hey Steve (and Don), I think he just called us OLD....

Smart kid ;)

Bob.
 

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292922
 

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Yeah, OLD friends....lol.

Bob. ;)
 

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93 NA ATX 3000gt DOHC
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Seems like it was only yesterday we were breaking in the new guy......;)
And you still are! .... Never quit learning even at my age.:sneaky:

Thanks I'll do that first! Where exactly can I find the ISC,
If you’re careful with meter probes, you can check the ISC/IAC pins without removing it. Just unplug the connector to get to the pins, should be plenty of room with you battery removed.

Hey Steve (and Don), I think he just called us OLD....
I think he meant the Stealth 316 and this site. But in either case he is CORRECT, just that you and Steve have been here longer than me …… Oh ….. wait does that mean you both are older than me :unsure:. :)
 

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Discussion Starter #152
Im baffled to say the least with the amount of knowledge shared within the community. For an awesome car nonetheless.

I tested the ISC pins exactly as shown and the resistance was 37.5-38.1 I unplugged the connecter and it seemed to idle better, or at least i think it did. I did not let it idle long enough for the CEL to pop back up as i didnt want to damage anything.

I have a guy near me selling a 93 3000gt non running but cranking, i may ask to rob a few of his parts as he is selling the whole thing for 700 but i simply have no room for another car!
 

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I tested the ISC pins exactly as shown and the resistance was 37.5-38.1 I unplugged the connecter and it seemed to idle better, or at least i think it did.
If that was the black bodied unit, that is probably within acceptable range since it would be a newer unit than the old tan top unit. If it was the tan top unit with max ohms of 33 that might be little high and out of range. Also assuming that all four readings was in that range, with none near a zero reading.

The IAC can’t smooth out a rough idle caused by something else, its main function is to keep idle speed between 600-800 RPM’s under different idle load conditions.
 

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Discussion Starter #154
If that was the black bodied unit, that is probably within acceptable range since it would be a newer unit than the old tan top unit. If it was the tan top unit with max ohms of 33 that might be little high and out of range. Also assuming that all four readings was in that range, with none near a zero reading.

The IAC can’t smooth out a rough idle caused by something else, its main function is to keep idle speed between 600-800 RPM’s under different idle load conditions.
It is the tan one. And it did raise the idle a bit but it was less choppy and less like in and out. It seemed like the miss was less prominent but it could just have been the higher idle making it seem less prominent. I read somegwre that you can clean it or something, do you think that's worth a try?
 

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It is the tan one. And it did raise the idle a bit but it was less choppy and less like in and out. It seemed like the miss was less prominent but it could just have been the higher idle making it seem less prominent. I read somegwre that you can clean it or something, do you think that's worth a try?
The cleaning process is covered in the link Bob (OhioSpyderman) supplied, but I personally don’t think cleaning it will help with a miss, more than likely just help if the idle speed couldn’t be controlled within the idle range by a good working IAC unit and no other existing problems.

If you have a miss when idling, pull one wire at a time from coil pack, if you find one that doesn’t make the idle worse, that will narrow down what cylinder is causing it. If no cylinder shows to be consistent with the miss, then it would be time to look for other causes which could be many possibilities.

That was one reason I questioned all four readings with none being near ZERO, which could be a sign of damaged ECU. I also fairly sure that’s why Steve ‘93ES mentioned doing IAC check first. A shorted IAC can cause damage as seen in picture below, that can cause missing and lots of other problems by the ECU.
ECU damage from IAC.jpg click on image to enlarge
 

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Discussion Starter #156
The cleaning process is covered in the link Bob (OhioSpyderman) supplied, but I personally don’t think cleaning it will help with a miss, more than likely just help if the idle speed couldn’t be controlled within the idle range by a good working IAC unit and no other existing problems.

If you have a miss when idling, pull one wire at a time from coil pack, if you find one that doesn’t make the idle worse, that will narrow down what cylinder is causing it. If no cylinder shows to be consistent with the miss, then it would be time to look for other causes which could be many possibilities.

That was one reason I questioned all four readings with none being near ZERO, which could be a sign of damaged ECU. I also fairly sure that’s why Steve ‘93ES mentioned doing IAC check first. A shorted IAC can cause damage as seen in picture below, that can cause missing and lots of other problems by the ECU.
View attachment 292932 click on image to enlarge
Okay, good info here. And I think I am mistaken and I have the BLACK one

So if IAC is good, I need to check ECU and injector resistance? Or is it injector voltage? I can't look it up right now but I do plan on going out to mess with the car after work and putting some time in cuz it's nice out today
 

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So if IAC is good, I need to check ECU and injector resistance? Or is it injector voltage?
Injector resistance is what you’d be checking which should be 13 - 16 ohms @68 degrees range, probably on low side if you don’t get injectors warmed close to that 68 degrees. I kind of assumed you 37-38 ohms on IAC were little low for black unit, because I figured you being in Illinois that is wasn’t 68 degrees when you took those readings.;)
I need to check ECU
It would be good if you could post few clear pictures of ECU board/components, we might pickup on something you might overlook.
 

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Discussion Starter #158
Cool cool, thanks. Is it a bad idea to leave the IAC unplugged?

I will take pics to have you look over

EDIT, forgot to mention, the AC motor assembly or whatever that hooks inline with the belt is literally completely unattached and is hanging on by the actual AC lines themselves!!! The belts on the engine pulleys are tensioned and tight, so it must have an AC delete belt or something haha. I dont see a way to even get that AC part out! Its too large
 

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Cool cool, thanks. Is it a bad idea to leave the IAC unplugged?

I will take pics to have you look over

EDIT, forgot to mention, the AC motor assembly or whatever that hooks inline with the belt is literally completely unattached and is hanging on by the actual AC lines themselves!!! The belts on the engine pulleys are tensioned and tight, so it must have an AC delete belt or something haha. I dont see a way to even get that AC part out! Its too large
No problem leaving IAC unplugged, as long as engine will idle steady at reasonable RPM’s.

Sounds like you have ½ of an A/C delete :p, which lacked removal of A/C compressor, lines, drier and condenser coil. Normally the compressor and alternator are driven by the same belt, so sounds like someone must have installed a shorter belt or maybe added another idler pulley just to turn alternator itself. Haven’t tried to remove the A/C compressor, but I seem to remember you have to remove the alternator and condenser fan assembly (one you rewired) to get enough room to pull compressor out after hoses and wires disconnected.
 

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Discussion Starter #160
the injector clips are very fragile. is there a trick to get them off?
 
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