Where can a get a direct source for an RPM signal?

[Suprapowaz!(2)]

Are all 89+ turbo models ECU pinout diagrams created equal? I have a 1991 Supra turbo.

I have this MAP ECU that is not getting an RPM signal. Until it does it will not tell the stock ECU what to do with the injectors. So my car ran as if it didn't have the AFM plugged in. I had to reinstall my AFM to get my car to run right. I have no CEL codes.

Where can I directly tap into to get an RPM signal? Does it come off the ignitor? I have my MAP ECU tapped into the IGT pin on the harness and it's not picking up the signal. I was going to try IGF, but that's just the return signal from what I understand. Is there another source?

BTW, all piggybacks need an RPM signal. This isn't a MAP ECU specific question. So if you have some other kind of piggyback please chime in where you found an RPM signal.

 

[bioskyline]

IGT should be correct, try the igt terminal in the check connector under to hood. myy vpc is ran to that wire for tach signal

 

[Suprapowaz!(2)]

I'll do that. Thanks.

 

[jetjock]

A minor correction: IGt is not rpm and doesn't exist in the diag block. IG does however and is what you need.

 

[Suprapowaz!(2)]

IGT does exist. I don't see an IG. Where is it?
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=D&P=33

Ok, ok. I see IG coming off the ignitor. One is going to the tachometer, the other to the check connector. I'll find it and tap into it. Thanks guys.

 

[87ttsupra]

Hope yours works I tryed the one for the diagnostic box and still no signal I tryed one wire off the coil and still nothin I think my map ecu was screwd..

If you get yours to work let me know what wire you hooked it to

 

[jetjock]

...IGT does exist...

Read much?

 

[SupraSean]

Ok, I have to thread jack for just a second, im trying to figure out which wires to hook up for the timing control on mapecu2. as far as i can tell IGda goes for cyl 1 and 6. IGdb goes for cyl 3 and 4. But it almost looks like IGT is for cyl 2 and 5? but im not positive. ive looked at a bunch of wiring diags and just cant get a definitive answer.. Anyone have any input?

 

[jetjock]

IGt is timing control. IGdA and IGdB control cylinder selection. If you think about it you'll see there's sufficient logic states between A and B to handle three sets of two cylinders each.

 

[Suprapowaz!(2)]

Read much?

:icon_redf

87ttsupra, I'll let you know what I come up with.

 

[Suprapowaz!(2)]

I connected it to IG off of the ignitor and got a signal. If you're looking at the ignitor side of the harness plug then it's the solid yellow wire. If you're looking at the main harness side of the plug then it's the solid black wire. Hope that helps you.

 

[RiyadYar]

which wire can i tap into close to the ecu . i dont see ig, only igt and igf

 

[Nick M]

which wire can i tap into close to the ecu . i dont see ig, only igt and igf

There is always Ne.

 

[RiyadYar]

There is always Ne.

Is Ne a square trigger wave? ...this is the type of signal required by my aem failsafe

 

[3p141592654]

NE is very sensitive. Don't touch it. You can find the tach signal on pin 4 of connector M1 near the ECU.

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=136

 

[Nick M]

Is Ne a square trigger wave? ...this is the type of signal required by my aem failsafe

http://www.autoshop101.com/forms/h24.pdf

 

[RiyadYar]

http://www.autoshop101.com/forms/h24.pdf

thanks ill give that a read and try to figure it out ..after a quick skim it only talks about square wave signal coming off of afm

 

[jetjock]

......

[video=youtube;KCfYWELLwZY]http://www.youtube.com/watch?v=KCfYWELLwZY[/video]

 

[Nick M]

What did you learn?

 

[Nick M]

..after a quick skim it only talks about square wave signal coming off of afm

The point of the link was for you to use critical thinking skills.