I just finished swapping the 870ecm for an 87 165ecm and harness, finally got all the wiring done, thanks to Trickster:hail: , but I am not getting a blinking light when I hook up my "noid" light and crank it over. I do have power at both term of inj. w/ key on. Any troubleshooting charts or tests or ideas would be great.

thanks,
Doug

 

What MEMCAL/PROM revision is in the ECM? What year '870 ECM is it?

 

He now has a 165 ECM in it from a 1987 camaro.

 

Thanks Trickster, those diagnostic procedures you gave me were very nice, but it seems that my ecm is bad according to them. Is it common to get two different ecm's from the camaro yard and them not be good? Maybe I can find someone here in OKC that will plug my ecm in there car and see if it works.

 

John, here is a post I sent to Big Chief on the parrells of a computer problem, just keep this in mind!

I had the same issue as you after I built a new 350 TPI for my '89 Firebird. The MAF had the correct output and the sensors were fine. Turned out I had a bad computer. Keep in mind a few things should you find this is the problem after replacing all the sensors. If it is your computer, make sure the company you buy a new on from replaces all 4 quad drivers which control the fuel injector pulse. If they do not you could experience the issues you are. 9 out of 10 times, if a computer goes bad, it is a quad driver issue. What the rebuild companies do is replace only the non-functioning drivers. Keep in mind if one driver goes damage to the rest usually occurs. However in a bench test the damaged driver may appear working well, but under driving conditions it is not working. In serve cases the problem can cause your exhaust cat to heat up and turn red. Also the computers in these cars can only diagnose problems in an engine to a limited capacity. The computer cannot diagnose a problem with itself. If it has a problem with itself, it thows a code for the most likely problem, even though it is the wrong one. Hopefully I haven't lost you too much. As for the computer make sure you talk to a remanufacturing company and request all 4 quad driers are replaced, it may cost a little more, but will save ya a lot of headaches in the long run!! Just something for you to keep in mind should your problem not be a simple sensor change!!!

Wayne Donovan

 

It can happen with the way those cars are treated in some of the junkyards. Exposure to weather and *** knows what else.

 

So I guess it wouldn't hurt to go ahead and get a new ecm, and thanks Wayne, I'll keep that in mind when I'm shopping around.
Hey Trickster, someone on the tpi board had mentioned that a bad injector can cause the ecm to not fire inj.'s. All of mine were @ 16 ohms, could one still be bad?

Doug

 

I replied to that post as well. There were some members on the board that had problems with Accel injectors several months ago. In your case you don't need to worry about that. As I mentioned in the other post, if the injectors you have are old and haven't had any fuel through them in awhile then they could be gummed up and stuck. A little injector cleaner would take care of that problem.

 

Cool I'll keep that in mind.
Something I noticed when I had all of the inj.'s unplugged and went to plug them back in, I didn't realize I had left the key on and I plugged 1 in and then as I plugged in a 2nd one I could hear the 1st one click and on down the line, but not all of them would make the others click when I plugged them in. I don't know if this might be a sign of something or not. Just thought I would mention it, even though I have checked all the wires to inj.'s and to ecm so many times I could trace them blindfolded.

 

I realize that you have a 1227165 ECM. Was it from a GTA by any chance? The '870 is essentially the same thing in a weather sealed case for underhood mounting.

What I was asking, and still would like to know, is what MEMCAL/CALPAK do you have? Open the ecm, Remove the CALPAK, Remove teh blue cover on the CALPAK, Read the printed code on the foil label on th etop of the PROM in the CALPAK. THAT is what I would like to know. Depending upon your programming, the ECM may be looking for a VATS input, or may have other issues. It may be expecting a CSI until 400 RPM is reached, etc.

 

I'm not sure if it was from a GTA or not, someone just wrote 86-89 tpi on it at the camaro/ firebird yard. The PROM in it came from the same yard but not with the ECM. It has 87 305 tpi wrote on it. As for the code on the foil label it readsELCO
APYN
3496
If you can tell me what this means that would be great, also if you there are any more numbers you think will tell you something about the parts I have let me know.
Also, the car is an 85 model, I think that the ecm for that year was an '870.? You mentioned something about under the hood, mine was under the dash on pass. side.

Doug

 

I ran that code number that you have listed across the ACDelco website checking the firebirds & camaros from 1986 through 1990. I found a code APYM but it didn't have the four numbers that you listed. I will check my other sources tomorrow.

 

Did you by any chance see a cope APYN, not M? The number could be 3498 instead of 3496, but it is definately APYN.
And thanks for your continuous help Trickster

 

Well after a couple of hours of reading posts from the past I came across this link,http://www.diy-efi.org/gmecm/ecm_info/1227165/
on that page it shows APYN3496 to be a 6e MASK ID which it says is an 89 calibration w/o the cold start injector. So am I seeing this right? If so then I actually have an 89 prom not an 87.
Could this be my prob. with inj. not firing? Also if it is an 89 prom then it would have VATS also? Right? therefore not firing injectors since my 85 ign. doesn't have chip in key? Please verify this for me if you can.

thanks

Doug

 

That is correct, I have just verified with one of my other sources at the parts department at the local dealership. That chip will only be found in a 1989 camaro with a 2.77 rear-end, 5.7L engine and automatic transmission. That chip also has VATS incorporated into it which would knock out the injectors.

 

:yes: :yourock: Well I think you probably get the point. IT RUNS AGAIN, YAHOO!!
From now on if I get any parts from the yard I don't care who says what they fit, I'm gonna verify it for myself!
Went back today and took my list of BCC codes to the yard and found a prom out of an 87, plugged it in and it started right up, runs grreat also.
Many thanks to everyone who replied to my posts I would never have got this thing going again w/o you all, especially you TRICKSTER:hail: ALMIGHTY. Your diagrams and tips have been the shiznit.
Just so every one will know, if you are swapping from an 870 ecm & harness to a 165 ecm and harness, the 86 model harness will plug right in place of the 85 harness as Jim85IROC did his, but however, and I knew I wasn't crazy, the 87 harness, which I ended up with, and not knowing until it was too late WILL NOTT plug right in! There are a few connectors onder the hood that have to be repined to the 85 conn., the I/P connector C207 has to have about 4 or 5 wires repinned and about 3 or 4 removed from dash harness and rerouted through the dash to connector C100, also had to repin the w/s wipers to the C100 conn. because that is even a different connector. But other than that, it wasn't too bad Don't know if anyone has ever don't this exact swap before but I sure couldn't find anyone on this or 2 other 3rd gen. sites who had. Now that I know what all has to be done to what, I don't think this would be all that difficult of a swap. And I can sure tell a difference in the way it runs and I haven't even tweaked on tuning it yet! Can't wait!
All this typing has worn me out as much as that car has,
gotta go,

Doug