DOOM Master

I finished completing my 165 to 730 swap in my 89 Camaro 5.7 TPI and was hoping someone here who has done this swap could help me with the issues I am having. I'm using a 730 PCM from a 92 with a 92 MEMCAL with a custom AUJP file to disable VATS and VSS buffer corrected, as well as improved fuel tables to allow better idle. I do my own tuning but I borrowed most of the info to start the tune from https://www.eecis.udel.edu/~davis/z28/ecm_swap_730/

I made a custom harness following the info on https://www.eecis.udel.edu/~davis/z28/ecm_swap_730/

I've quadruple checked my pins to make sure they are correct, so I don't believe that I have a pin wired incorrectly.

I used the jumper method to bypass the ESC with the 3.9K resistor. I added the 3 wires for the MAP sensor rather than converting the MAF wiring over.

The car will start and idle around 1500 with no surging and does not run very rich. The #1 fan is on all the time due to the SES light but there is no ALDL data from the port and the cigarette lighter no longer has power. I've tried both the paperclip method to pull codes as well as my ALDL adapter to try to get data from the ECM but neither will work at all.

I unfortunately can't take her out and drive her yet as it is too cold and salty, so I don't know how she drives with the 730 ECM but idle and high rev does not seem to run poorly. Since I can't get ALDL data I can't pull whatever codes it is throwing, although I haven't tried manually jumpering it from the ECM yet. I wanted to see if anyone else had run into a similar situation before I continued with any further tests.

I did swap back to the old 165 ECM and it still has the same issue, no ALDL data or cigarette power, as well as the #1 fan on with the SES light. Idles at 1500 well and isn't running rich.

Any info would be highly appreciated.

Tuned Performance

iTrader: (92)

The aldl data stream moves from e to m or you can even have it in both cavities.
Sounds like maybe the iac is wired incorrectly.
Your aldl has a ground going to the back of the drivers side cylinder head.
Check the connections at c207.

DOOM Master

Thanks for the info. I have a Tunercat USB ALDL adapter that is setup for both the older 165 ECM on the E location (with the 10K resistor switch) and for the newer ECM/PCMs that use the M location. It worked fine before the swap on the 165 ECM and stills works fine on my 94 Z28 and 95 Tahoe, which both use the M location. So it seems like I have an issue with the ground possibly. Could this also be tied in with the cigarette lighter, which is causing its power loss as well as the ALDL loss of data?

I will recheck the IAC wiring just to be sure.

C3 (IAC "B" Low) GE6
C4 (IAC "B" Hi) GE5
C5 (IAC "A" Hi) GE3
C6 (IAC "A" Low) GE4

That is the info from https://www.eecis.udel.edu/~davis/z28/ECMs/86to92.txt, which is what I used to wire my adapter. I'm not familiar with what the c207 connection is suppose to be, is this a connection somewhere on the ECM or is it located elsewhere? The C/D connector only has 32 pins total, 16 on top and 16 on bottom, on both the 165 and the 730 ECMs.

Tuned Performance

iTrader: (92)

You might want to check continuity on the white/blk wire it runs through connecter 207 next to the ecm left hand side.

http://www.austinthirdgen.org/mkportal/modules/contents/images/Connector_1989_C207.gif

RBob

iTrader: (1)

With the SES always on and the primary fan always on, either the ECM is in limp mode or the CTS is bad and tossing a code.

If you jump A&B on the ALDL connector and key-on, engine-off, does the ECM blink out the code(s) on the SES light? If not then limp mode.

If it does blink out the codes then get the code by counting blinks and go after it.

If the fan runs at key-on, engine-off, then limp mode.

There is another test you can do, you've been around for a while and do your own tuning, you should already know about it.

RBob.

DOOM Master

I know its been a few week since I last posted but I finally had a chance to really spend some time working on this again today. At this point I have to have some sort of sensor issue that is causing the problem, as I have checked the connections and grounds from the ALDL to the PCM, as well as the C207 connector. I have good continuity from the A spot on the ALDL all the way to ECM.

I also did a pin for pin verification of continuity on my adapter to make sure I did not have a miswired connection anywhere. Everything is correct from the 165 to 730 adapter pinouts. I also tried another ECM just in case but that did not help, just the same as swapping back to the 165 ECM still results in the same issue.

Since I did not swap to a new knock sensor and used the resistor bypass method, can the knock sensor or the ESC cause the ECM to be stuck in limp mode and refuse to send ALDL data or flash codes?

Tuned Performance

iTrader: (92)

Resister bypass ? Hooking a 3.9k resister on the memcal ?
You know the 165 netres will work in the 730 with appropriate programming.
The 100 ohm tpi maf ls can be using in conjunction with the 730 if the input is hooked to pin b8 of the 730.

DOOM Master

Not on the memcal, the 3.9k resistor is suppose to be hooked between the wiring on the ESC.

If you are using the ESC connector on the firewall to bring
the KS signal in, you will have to jumper pins "C" and "E"
on the ESC harness plug. While you are building the jumper,
you can add the resistor between the jumper and pin "D"
(making it a 3-prong jumper) and your '165 KS will be properly
biased for use in the '730 ECM

I'm going to start here and try getting a proper 90-92 knock sensor and hooking it up directly. It appears also that the 730 ECM doesn't use the ESC module, as there doesn't appear to be one that I can find in the wiring diagrams. The ESC on my car is original as far as I can tell, maybe it was already in the process of failing and caused an issue with the knock sensor? I've never heard of a failed knock sensor preventing the ECM from flashing the codes but its possible. If that doesn't help I'll start checking the sensors one by one to verify operation.

DOOM Master

Also forgot to add that I am not using the MAF, I converted to the MAP. The MAF wiring was left stock and I just left the pins unused, I added a new MAP connector directly to the 165 to 730 adapter harness I made.

Tuned Performance

iTrader: (92)

Why wouldn't splice the wires going from c to e and use the proper 3.9k ks ?
Or just feed the knock signal to b8 of the 730 just curious ?

DOOM Master

According to the info on https://www.eecis.udel.edu/~davis/z28/ECMs/86to92.txt, B8 isn't used on the 730 for the conversion.

BB8 N/C

This is where the ESC Signal is from there.

B7 (ESC Signal) GF9 (req new, direct fed knock sensor
or ESC jumper and resistor)

GF9 is where I have the knock sensor connected with the jumper that is described. Perhaps this info is incorrect?

DOOM Master

Well after spending a few more hours going over the sensors I have finally found the culprit. Turned out to be a bad 27SF512 chip that won't hold the program anymore. I loaded a new chip tonight and now I have ECM communication again. Guess I should have started there first and saved myself some time and effort. Thanks for your help and info Tuned Performance.