Ideas for 4 cylinder MPFI = Toyota 22RE with GM ECM?

[EagleMark]

try this for shits and giggles cut and paste from our aussie delco master vl400 reguarding sensor polarity :D maybe you need to reverse the crank sensor wires

Well Son of a Bitch!

I'd have never thought of that and was not even going to try, but I'm glad I did. Soooooo much better. Maybe it's tunable now? I've got to solder and shrink wrap the two crank sensor wires and try again. I had them twisted and taped and if I pinched them it changed something...

It actually idled... almost. I've had the external IAC pinched off because the Jeep IAC is backwards? IAC counts of 0 = full air! Tried to put a GM IAC in the Jeep IAC housing, although they look identical a closer look showed enough difference that it won't slide into housing. Wonder if swapping 2 blue or 2 green wires would make it work right?

[JeepsAndGuns]

On the jeep 4.0 IAC, the pins are marked ABCD

So try this:

A - Blue with black stripe
B - Blue with white stripe
C - Green with white stripe
D - Green with black stripe

I came up with this with my test bench. I used the IAC from my 93 wrangler and used a 7727 ecm, the harness is a stock GM harness I have hacked and added ecm connectors from a 7727, 7730, and 7427. I would power on the ecm, the power it back off to do the IAC reset. I unhooked the battery each time so I could make it do the reset each time. I just kep swapping wires till it worked....lol. I did this to figure out the wiring for the IAC for when I eventually swap out the stock untuneable jeep ecm for a tuneable GM ecm (7727)

Hope this helps.

[delcowizzid]

you will probably find that the sync pulse cam signal you were messing with will work now too.and you may need to change the air gap again.glad i could help many brains many ideas you did say you thought it was a hardware issue and it was LOL

[delcowizzid]

post a new log so we can see the difference in rpm spikes

[EagleMark]

Tried the IAC wire change but it still did the exact wrong thing. Swapped 2 and still? So I need to work on IAC issue.

But I can get it to idle, I think this mask has issues with IAC counts and idle. Revs up and pulls good. Here's a log to look at. I'm whooped and need to hang out with my chair for alittle while. Feelings now are it's in the tune along with IAC issue.

[delcowizzid]

oh my what a beautiful rpm trace now LOL pretty damn smooth

[JeepsAndGuns]

Tried the IAC wire change but it still did the exact wrong thing. Swapped 2 and still? So I need to work on IAC issue.

Humm. What year did the iac come from? I know this worked with the factory iac from my 93. I remember when trying to find the right combo of wires, having the same issue, it worked but was opposiate, I swapped two more wires and then it worked like a charm, thats the above combo I wrote down for future reference.
I just pulled up the wiring diagram for my 93 and it shows pins A & B as one coil, with pins C & D as the other coil.

[EagleMark]

Well I got the Jeep IAC worked out today and the Toyots runs great from cold start idle to warm start and driving!

Well OK still needs a final tune but we are in ballpark!

Since the Toyota does not have a IAC that would work I used the trick from 1projest2many and got a Jeep 2.5L or 4.0L IAC and housing. A GM IAC looks identical, but is not and won't fit.


Use the Jeep IAC housing and make a plate for back with hoses and POOF! And external IAC for conversions.


and


But the Jeep IAC does not have the coils set up same as GM!

GM A-B and C-D
Jeep A-D and B-C

Also direction comes up backwards if you just swap over. So you'll notice the power wire = White stripe are swapped as well!

Final wiring from GM to Jeep IAC in tested working condition on the vehicle is.

A = Blue/White
B = Blue/Black
C = Green/White
D = Green/Black