16168625 pcm

[jim_in_dorris]

Ok, I pulled the pcm out of my son's worn out 93 S10. It's a 16168625 PCM. The question is, are there any good hacks for this PCM, or should i just wait and get a 7427? My 87 has a 747 in it now, and the 7427 plugs in with a pin swap. I would assume that the 8625 would do the same. The big difference I see is that the 8625 had the ESC module attached to it and i am not sure where the ESC module is in my truck

Next question, the S10 had cruise, can I pull the parts and use them on my 87 fullsize 4x4? I know it means pulling the column apart, not a big deal as the truck isn't a DD right now ( gotta do a tranny anyways, at minimum) I also have a 90 astro van with cruise, if that would be better, all 3 are TBI engines.

[93V8S10]

My S10 originally had the 8625 PCM. To the best of my knowledge it will run $0D(same as 7427) and the 8625(93), 6395(94), and 7427(95) are interchangeable, but most people prefer the 7427. The ESC is not attached to the PCM. What your seeing attached is the DRAC module for the S10. The ESC is internal. Also one other thing that will be special about this PCM, if it's from a 4.3L, is it will require two knock sensors. Use the same ones from the 4.3L, but put one one each side for a V8, don't put in 4.3L locations they won't work well with a V8.

[jim_in_dorris]

ok, my 87 doesn't use a drac, will I need to use it? Yes, it is from a 4.3. I assume that the location of the stock knock sensor on the 305 is where they should go ( 1 on each side)

[93V8S10]

No, the DRAC isn't a part of the PCM, it's just mounted there in a S10.

After thinking about the knock sensors some more, I realized, I never completely figured out what the difference was between the one knock sensor system and the two knock sensor system. The difference may not be in the PCM, but may be in the wiring harness used. I would try it first with just one of the 4.3L knock sensors. If it doesn't work, then I would add the necessary wiring and second sensor.

The right side 4.3L knock sensor won't fit in the block drain hole, on a V8, so I used one of the mechanical fuel pump bolt holes.

[jim_in_dorris]

93, I understand that the DRAC isn't part of the PCM, my question revolves around the fact that my 87 VSS signal is generated at the back of my speedo, and supplies the ECM with the VSS signal. With the $0d mask, does it require a DRAC input, or just the VSS signal? Also, I understand that I will have to disable the 4l60E tranny code as I have a 700r4, how difficult is that?

[neoblood]

I have a 93 s10 and a 16168625 and it runs 0D code just the same as a newer pcm. As far as the tranny code for some reason gm put the code for a 700r in even though these pcms only used 4l60s. I don't know if you need the drac input for a 700r or not, you may just need to disable the error code. But I do know that the VSS cannot be directly connected to the pcm.

[93V8S10]

Originally Posted by jim_in_dorris

93, I understand that the DRAC isn't part of the PCM, my question revolves around the fact that my 87 VSS signal is generated at the back of my speedo, and supplies the ECM with the VSS signal. With the $0d mask, does it require a DRAC input, or just the VSS signal? Also, I understand that I will have to disable the 4l60E tranny code as I have a 700r4, how difficult is that?

I'm not familiar with the 87 system, but I would say yes, you will need to install the DRAC or a VSSB. Here's a recent thread: http://www.fullsizechevy.com/forums/...cm-issues.html

It doesn't appear to be very hard to disable the 4L60E code. I've tried to help some people in the past with doing this. I don't fully understand it yet, but I would be willing to help. I hope to eventually convert my 91 S10 over to $0D, it has a 700R4.

[Fast305]

Originally Posted by neoblood

I have a 93 s10 and a 16168625 and it runs 0D code just the same as a newer pcm. As far as the tranny code for some reason gm put the code for a 700r in even though these pcms only used 4l60s. I don't know if you need the drac input for a 700r or not, you may just need to disable the error code. But I do know that the VSS cannot be directly connected to the pcm.

The 700r4 code is in there for the same reason as the manual transmission code. Some vehicles used these PCMs with both. The 700r4 was used in the early model CPI Astro/Safari vans, running $OD and a 700r4. The manual transmission side of the code was used with the 4 cylinder S10s and the 4.3 TBI 5 spd trucks.

[neoblood]

I didn't know that. I thought only vehicles with 4L60Es use the 0D and E6 code. My brother has a 92 s10 with a CPI engine and a 700r and it uses an older ecm. I don't know with one ,I never looked, but I know its older because it uses a 160baud connection for the ALDL.

[jim_in_dorris]

ok, I guess I will need to get the wire harness for the drac out of the S10, then figure out how to wire it up, hopefully it will integrate with my existing VSS, or else I may have to do major surgery LOL. Thanks for the input so far, the 0D code looks a lot better documented than the 747 stuff i have been staring out for months now. I am thinking that I can start with the memcal from the 4.3 and change the injector size and cylinder size and then start from there.

[neoblood]

You can't start with the v6 memcal. The injector timing is controlled by the resistor pak on the memcal and so the injectors are fire differently. You need a v8 memcal.

[93V8S10]

The MEMCAL will work if it's from a TBI V6, but if it's from a CPI V6, it won't work, unless you cut the jumper wire out.

[93V8S10]

Originally Posted by jim_in_dorris

ok, I guess I will need to get the wire harness for the drac out of the S10, then figure out how to wire it up, hopefully it will integrate with my existing VSS, or else I may have to do major surgery LOL. Thanks for the input so far, the 0D code looks a lot better documented than the 747 stuff i have been staring out for months now. I am thinking that I can start with the memcal from the 4.3 and change the injector size and cylinder size and then start from there.

HTH
http://www.jagsthatrun.com/V8-chapte...ed-Sensors.pdf
http://www.jagsthatrun.com/index.html
http://www.tbichips.com/drac/
http://614streets.com/drac.html
http://www.philter.com/cgi-bin/drac.pl