Ok, this has me baffled, completely. Pulled the pins from my original '302 harness, repinned into a set of '730 ecm harnesses, as per the SyTy.zip pinout.

Spit out a quick chip @ 126 BPC. Car will fire and start immediately, run for like 2 seconds, and die out. It's exactly like it fires the injectors, and then stops firing them.

Now, the '302 has 2 driver outputs for each bank. 2 sets of 1,3,5, and 2 sets of 2,4,6.

So I just combined them into one line, and hooked it up.

I don't know the technical data, but can the '730 ECM (running $58) NOT fire the injectors? I'd love a '730 ecm pinout from the V6, 90-92 Fbody ($88 mask).

I don't understand what the point of running 2 seperate lines to the injectors is. Has it something to do with the ohms?

Terribly confused, and bummed out. Help?

And while we're at it, WHAT IS THE CORRECT IAC PIN for the '730 running on the '749 code. Wonder if I've got them wrong?

 

'88 Camaro 2.8 and '90 Sunbird call for the same IAC motor.

Going to re-pin the IAC part as though it were a sunbird, and see what happens.

Both call for an AC102.

The '91 Syclone calls for an AC114.

We'll hope for the best. -.-



omfg. Nothing. I pulled the error codes, 12, 43, 51. -.- Looking those up... probably whining about no knock sensor hooked up

Also, the IAC never started 'clicking' like it should... ideas?

 

Uh, Maybe This one half way down the page from last week...
$58 IAC pin swapping

 

Tried that, nothing.

 

With the AC114? Which is also what a TPI calls for.

 

Should be. The Syclone/Typhoon uses a V8 TPI throttle body.

 

I did the 730 with $58 code last week. Been tuning for a while now. I would like to see you getting yours running for more than 2 seconds. I will take a look at the 1990-92 V6 diagram and see how much if differs from the 1990 V8. Maybe something will stand out. I will post tomorrow what I find.

J

 

I looked at the 1988 Camaro V6, 1988 Camaro V8 TPI, 1990 Camaro V8 TPI, 1990 Syclone turbo schematics.

I am assuming that you repinned a 1988 Camaro V6 to use a 730 harness with $58 code in it. One question, did you ever have the car running before with a 730 ECM and $8D code in it?

After looking at the schematics and assuming that the 1988 V6 was properly repinned to a 730 ECM with $8D code I can only assume that one thing could cause stall condition due to wiring. And that would be incorrect IAC wiring.
The reason the IAC wiring is so confusing is because GM changed how operates the IAC pins. GM also changed the wiring AT THE IAC pins (not ECM pins) on different vehicles and different years. The IACs themselves operate the same across vehicles and bins.

Here is a summary of ECM pins, IAC pins, code, and wire color

I did not verify this info on a vehicle. It is strictly from the schematics I have and info from this board (the $58 bin IAC wiring error is in the schematic I have).

As for the injector wiring. You shouldn't have to touch it. GM used two wires because of the amount of current through the wires AND the ECM pins. A connector has an amperage rating. It is quite common to use multiple pins on a connector with only a single wire feeding the pins.

 

I appreciate the info. It's running longer (before, it would crank, fire VROOOoooommm die) than it did - now it will fire, run for about 3 seconds, then die. I actuallly think the IAC motor is dead - I can hear it humming, but nothing after

Going to bypass the IAC for a moment, and see if it will run without it.

No, I never ran the $8D code - straight from the '302 ($3A mask, btw) to the '730 (running $58 code)

 

might be silly, but double check your fuel pump wiring. sounds like the ecm is priming the pump, then for whatever reason, the pump isn't continuing to run? long shot, but maybe.

also, does that mask have VATS?

 

Completely said SCREW THE IAC. Unscrewed it all the way out (the pintle) and put a 5/8" cap on it. Also plugged the hose from the back of the manifold

Car will idle by itself for about 9-10 seconds (timed it, lol) hovering between 750/600 rpm idle, then dies out.

Still code 43. Low Voltage at EST sensor?

No VATS in the code...

 

I've got it idling. How? Zero'd out the idle underspeed spark advance table. For whatever reason, the ecm seems to be having WAY too much fun with the timing.

I'm going to let the car totally warm up, let the ECM do a little learning, and try to figure out why I'm getting the code 43

4.6V running on C7
1.3V running on C8

Code 43 is coming up low voltage on the ESC.

wtf... is it because I have no knock sensor hooked up? I unchecked 'Knock Option Enabled' under ECM Switches in TunerCat... *sigh*

The car will run now, though. No more code 51 error. Only 43. I'll wire up the knock sensor tonight, and see if that maybe fixes it.

 

The wild idle timing is probably due to the two spark correction tables vs. idle rpm error. I set mine to the $8D settings. The stock $58 tables will change spark advance up to about 10 degrees each way depending on rpm error.

You can check the IAC for proper operation. That is how I figured out the wiring for my swap. I installed a stock 730 $8D bin with stock 1990 V8 wiring. I jumpered the ALDL A&B pins and looked at how the IAC was responding (all the way open). I then removed the jumper, turned the key on and looked at the IAC (3/4 way open). I then installed the $58 code in the 730 and did the same test. I ended up getting the IAC to work the same using the wiring listed above. I did all my tests with a spare TB so I didn't have to remove my TB IAC lower plate. I think the IAC will completely unscrew if you do the test without the IAC in a TB.

Code 43 is a knock sensor malfunction. Most likely because the sensor is disconnected.
I am guessing the $58 does a knock sensor test on startup because I now get knock counts on startup. Just a guess. I wonder if the TC knock option is only for running a knock test.
Good to hear that you are making progress.

 

I've got a knock sensor now, gonna post in the V6 forums to see where it goes

Building the 2 transistor cable right now, then I'll go hook it up to the car, see if I can get a little TunerCat tuning action going, to try to tune it some tonight

Here's hoping...

 

With the knock option "disabled", the calculated spark offset due to knock won't be applied. I believe the knock sensor is still read and can be seen on a scan tool. But, the timing shouldn't be adjusted for the value that's being read.

Of course, that only happens if Code 43 is clear. If the code is set, a calibratable default spark retard is applied (located at $X093) regardless of the option bit state. From what I can immediately see, Code 43 will cause this default retard *and* disable the premium fuel detection algorithm.

I think the best approach (which is what you're doing) is to install a knock sensor. Otherwise, I'd suggest disabling Code 43 so the default retard values don't apply.

 

How do I disable code 43?

Is that an option bit in the BIN?

Appreciate the info I've got TunerPro and 58.ecu (the BIG one) from moates.net...

I'll be hooking up the 2 transistor cable in a few minutes, and we'll see if I can get a datalog from TunerPro

Cable seems to work great, but I can't get a hook up to TunerPro... TunerPro says cable found and functioning... Is there anything funny I have to do, regarding a 10k ohm resister and a couple pins?

 

When you import the .ecu file to Tunerpro, you should find a flag labeled : "MALFUNCTION FLAG MASK 3 - Bit 7 - 43 " Uncheck this option. If you're using some other application to do this (or a simple hex editor), you want to have address $X037 / Bit 7 cleared.

You don't need a 10k resistor to connect to the ECM. While this hasn't been a problem I've experienced with Tunerpro, I have had problems connecting the 749/$58 to other scantools/software. In these other applications, I'd have to try to connect multiple times before the computers would talk. I ultimately built a MAX232 version of the cable which helped improve my connection success.

 

How's it running? Get it all straightened out?

MAX232 is the only way to go. The two transistor thing doesn't meet any specs and is only a hack. A lot of the LT1 PCM programmers find that out when trying to flash a PCM with a two transistor setup.

You would be surprised what you might find in a ROMULATOR.........no max232 to the PC. Just a hacked two transistor device with all of the other commercial (not automotive) grade parts. That means it isn't guaranteed to work at less than 32 degrees F. I guess reliable tuning in the winter is out of the question. Do they tell you that on their website........I couldn't find it.

J

 

2 transistor cable works great.

I'm a stupid SOB - I had the ZT-2 dongle still hooked up on com 1, NOT the cable I built.

Datalogging fine! See the new post for the latest question... and yes, it's running now

 

You may be lucky that your logging equipment (PC) meets or exceeds the RS-232 spec., but that doesn't mean that it will work over all temperatures and laptops or ECMs.
I am not knocking the two transistor design for doing hobby stuff like messing with cars to read data. But it does make you wonder about things like emulators.
It is good to hear that you have the ALDL connected and the engine running stable now.

 

I still haven't gotten the IAC going... Externally, the AC114 and the AC102 look identical.

There's got to be something different in the coils themselves... I'm going to look up some 8D 730 pinouts, and see what the wires are labeled as, and color coded as.

This IAC problem is really pissing me off. Runs great, outside of that!!

 

I spent a fair amount of time looking at the IAC thing today. I did a bench setup using a 730 ECM with a stock BBZB bin installed. I looked at the Syclone and 1990 Camaro V8 TPI diagrams. I looked up how bi-polar stepper motors work. I ohmed out a 749 ECM and I ohmed out a 730 ECM for the IAC traces/wires on the PCB. I looked up and tested both GM screw-in IAC and the GM bolt-on IAC that has the coil wires in pairs (there is two versions).
Here is what I found:

The 730 and 749 ECMs have the same exact wiring on the PCB.
The $8D-AUJP and $58-BBZB have the same exact IAC code.

** So why the difference in operation? **
It is STRICTLY because of how GM installed the wires into the IAC connector AT THE IAC.
Looking at the Syclone schematic that is something I overlooked early on. The Syclone has a different wiring at the IAC connector and therefore requires a different pinout at the ECM (the schematic is wrong also, the wires are reversed).

If wiring according to the www.speedtoys.com page what you will get is the IAC operating as it would if YOU DID NOT move any pins at the 730 ECM connector.

I tried all kinds of wiring configurations with both the screw-in IAC and the bolt-on IAC. The end result to have the IAC working properly on a 730 ECM with the $58-BBZB bin is to NOT move any of the IAC wires at the ECM connector if your wiring at the IAC is a stock 1992 Camaro TPI v8 pinout.

Ignore the IAC wiring diagram for the Syclone. Verify that your wiring is correct at the IAC connector and ECM connector as per 1992 Camaro v8 TPI wiring diagrams. The IAC will then work correctly.

This is for the screw-in IAC
If you use the bolt-in IAC, note that GM pinned them out differently at the IAC connector. MAKE SURE that you verify the IAC connector pin label (A,B,C,D) goes to the correct ECM IAC pin. That is why I listed them. Wire color really doesn't matter but helps to make tracing the wires to the ECM. Also, note the reverse of the wiring between the "LT1 and V6" IAC verse the "old camaro, screw-in" IAC.

I spent quite a bit of time looking into this, even made a few code changes to the BBZB and compiled to reverse the IAC operation. What I write here is correct. If any one doesn't believe it.......prove me wrong. Ha ha, just trying to push anyone to try it for themselves and verify.

Anyway, if using a 1985-1992 Camaro TPI V8 setup using the 1990-1992 730 ECM Camaro wiring diagram.......don't repin the IAC wiring. If using an bolt-on (LT1 and some V6s) then wire it as posted above. Make sure that the IAC connector wiring matches the above list if you don't understand (and/or don't care to) how this works.

All the confusion comes from the IAC connector wiring and the differences between the screw-in and bolt-on IACs. The code is the same and the ECM printed circuit boards are the same.

J

 

Is your IAC a screw-in type or bolt-in type? It matters.

J

 

I looked up the 1988 V6 IAC and 1988 V6 wiring diagram (again). If my schematic is correct, then you need to repin the ECM as listed for the screw-in IAC as listed above (using the screw-in pinouts). My schematic shows that the 1988 V6 IAC is pinned the same as the 1988 V8 TPI. If the IAC operates the same as the 1988 TPI IAC then the operation will be correct if you wire it as listed above. In your case, you can also go by the wire colors listed. If in fact, the IAC is different internal then it will operate in a reverse fashion. Please post if it does, I don't have any V6 IACs here to test.

J