Drivetrain AOD to T5: random codes/issues

fox racer v2

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Hey folks, finished up my AOD to T5 swap this weekend. Ran into some weird issues detailed out below. Before the swap, I had code 67 on KOEO testing.

Background: When pulling the car into the work area, it was freezing. The starter solenoid got stuck and cranked for like 45-60 seconds and a buddy had to smack the solenoid to get it to stop. After this, tried to start the car and it didn't crank (fried the starter) but the negative terminal got really hot. I've since replaced the starter (PA Performance mini starter) solenoid (Motorcraft) and starter cable (LMR) and it turns over just fine.

I started the car after the swap and got codes 67 and 24. Re-ran codes, got 67, 34, and 22. Removed the negative battery cable to help reset, and got codes 15 and 67. Reset the code 15 by re-running KOEO test, and pulling the STI/signal wire as the codes started being pulled. Finally, after all is said and done, I consistently have codes 22, 34, 63, and 67.

Issues:
1. Codes 22, 34, 63 all have the same ECM pin in common, 46. Is it possible I fried this when the starter solenoid went? The commonality has me concerned a bit. I'm still trouble shooting (need to test harness and the PCM) but really curious if anyone else has had this issue before or if it's even possible.

2. I have a high idle (1200 ish) since the swap. While this is an issue in and of itself, I'm troubleshooting separately. However, when the car is idling I do not have check engine light. As soon as I put it in gear (any 5 forward, OR reverse) the idle jumps to 2500 and check engine light comes one. This only happens when I put the car in gear.

Each time, it had a hard start (had this previously, but it was intermittent before the swap). When it runs it it does surge, but eventually levels out after a few minutes.

Anyone have experience with these issues or any thoughts? My concern is the codes changing over the few times I ran the codes, this sounds like a ground/ecm issue.
 
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John Dirks Jr

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What year are you working on? MAF or Speed Density?

In these swaps there are sometimes modifications that are needed to the O2 harness pin configuration. Might depend on which ECU you have, A9L or A9P.

So, what year car, MAF or Speed Density, what ECU, what is the current configuration of the O2 harness pins?

It might seem picky to to ask all these questions but heres why its important. Du to the age of these cars and the fact that most of them have had multiple owners who do modifications, knowing exactly what you're working with is important.
 

John Dirks Jr

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I've recently run in to ECU problems. Bad capacitors. Apparently these things are now failing at a high rate due to age. I recommend at least pulling the ECU, removing the cover and visually inspecting for signs of capacitor oil leakage and corrosion at the pin connections to the circuit board.
 

Mustang5L5

This is a big reason why I pulled it out
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What year is the car, what ECU are you running, and what wiring harness were changed as part of the 5-sod swap?
 

fox racer v2

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Right, should have mentioned in the OP:

1989 LX, Stock A9P ECM, stock O2 harness, T5 trans harness from an 87-89 GT.

Given how erratic its acting, I do think it's the ECM somehow
 

fox racer v2

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That they are. The NSS and NGS are plugged in on the pedals, I put a new NGS on the T5 before I installed it as well.

Also makes sense to note: we checked a bunch of wires/vacuum lines to find pinches or a issues.everything looked ok. We swapped out the BAP/MAP sensor (think that is code 22) with a known good one but still got that code. TPS voltage is good too.
 

fox racer v2

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Editing post to keep clutter down:

The car has a T5 harness with an A9P and AOD 02 harness (to be confirmed this weekend, but 99.9% sure its all original, so for the sake of discussion...). Unless I'm reading all these diagrams wrong:

OEM 1989 T5 wiring: Pin 30 -> O2 harness loop -> trans harness -> Parallel both NGS on trans and neutral sense on pedals (through circuit 199 & 359) - > Pin 46 through circuit 359

OEM 1989 AOD wiring: Pin 30 -> O2 harness loop -> Circuit 26 (I can't follow where this goes. Wiring diagrams say section 16A but don't see the corresponding circuit 26 in 16A or a W/P wire in 16A...)

So now that my homework is done, I plan to:
- On the ECM, check pin 46 to pin 40 (on my A9P) for resistance <1ohm (if this and/or below fail, my ECM needs some TLC)
- On the ECM, check pin 46 to pin 60 (on my A9P) for resistance <1ohm (if this and/or above fail, my ECM needs some TLC)
- On the ECM harness, check pin 40 for continuity to ECM quick disconnect just before the ECM ground on the driver side fender apron (If this fails, I have an ECM ground wire issue)
- On the ECM harness, check pin 60 for continuity to ECM quick disconnect just before the ECM ground on the driver side fender apron (If this fails, I have an ECM ground wire issue)
- Check continuity from EEC ground quick diconnect (ECM side) to negative terminal (If this fails, I have a negative terminal cable issue, possibly ECM quick disconnect failure)
- I'm going to check my O2 sensor harness loop to ensure it's wired for AOD based (Pins 5/6 looped)
- As it's wired, I'm going to pull the ECM, turn the motor over and test ground to Pin 46 on the harness side of the ECM harness. If there's power, I know why Pin 46 is dead
- I'm most likely going to A9L. This will require me to update the O2 harness loop to Pins 1 & 5 on the o2 sensor side of the o2 sensor harness

Still lost on:
- Why the hell does the CEL come on and RPMs jump to 2,500 when in-gear but not neutral? Pins 30 and 46 are linked, could be something there
- High idle (1,200 RPM) - possible link to code 67.
 
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fox racer v2

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Alright folks, did some diagnostics and found some interesting and hopefully definitive things:

- Tested pin 46 to each pin 40 and pin 60 on the ECM. There was no continuity (wanted to check for <1.5 ohm for each). ECM also smelled like burnt electronics, so here's part of my answer.
- Tested ECM pins 40 and 60 from the ECM harness side to the ECM ground up on the inner fender well (by the windshield fluid reservoir) and I had continuity but didn't check resistance.
- Tested pin 46 for power when turning key to start (ECM disconnected, checked harness side) and GOT POWER to pin 46. Re-pinned the o2 harness to mirror an 89 t5 setup (pin 1 & 5 on the o2 harness is now looped). Re checked pin 46 for power when turning the key and got no power after re-pinning.

So I think I have my answers: I fried pin 46 on the ECM upon initial start up due to the o2 sensor harness. This probably led to all those pin 46 (on the ECM) related codes.

The 'interesting' part: the o2 sensor harness itself appears to be some sort of aftermarket version. The wire colors are not correct to my wiring diagram (ECM side is correct) but the wires are labeled indicating what they're being used for. Like I mentioned, I re-pinned the o2 side of the harness to loop pins 1 and 5 and no longer got power to ECM pin 46 when starting the car. The harness was originally pinned 1 to 6 on the 02 harness, which by my recollection, is the factory t5 wiring for 91-93, I'm not sure why this sent power to pin 46 but it did.

Also, my computer as some point was rebuilt/fixed. I'll get pictures when it's back open, but I have wire bridges on the thing that I don't know what they are doing (the pin 46/40/60 fix is not done on this ECM). I have a feeling my A9P is garbage at worst, Frankenstein at best, so will be replacing it with an A9L now that the o2 harness and trans harness are correct for an 89 t5.
 

fox racer v2

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New ECM and ran codes: 11-10-11
Put in gear, no surging idle
New T5-Z swapped in
Old problems are cleared up! But...

1. Think e-brake is hanging - rear wheels are very difficult to turn. Enough that when I put the car in gear while it’s running (on jack stands) it will stall in 3rd and nearly stall in 2nd. Gotta figure that one out.
2. Stock fan now hits the bottom of the shroud. Think the new trans mount maybe be the reason (mixed with worn engine mounts) but the car *was* bumped up front and while nothing is obvious, it could be a radiator support issue. I’m just going to trim the shroud short term so I can drive the damn thing already - need to put it away in the garage already!
 
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John Dirks Jr

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I had the fan hitting the bottom of shroud on the vert. I put a few washers in between the motor mounts and block along with slightly longer bolts to ensure enough thread grab. Worked great to lift the motor just a bit
 
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