87 ECM in an 85 GN?

[Daniel Jost]

im ready to put new fuel injectors in my car and when I look at the "for sale" board I see that almost all the injectors have an 87 ECM chip to go with them, and i have decided to put an 87 ECM in my car. how hard is it to put an 87 ecm into my 85 GN, what do i need to get for the swap? HELP!!!!!

 

[Daniel Jost]

http://www.gnttype.org/techarea/ignition/module.html , i love this site there is so much info, is there anything else i should know about this swap, i remember hearing something about having to put some other sensor in.

 

[HOTSIX]

ecm

Pretty easy swap - 2 main reasons you do it are:

Choice of chips and elect fan control

Info provided is greater to scantool like Turbolink etc. to tune

I did it - took only a few hrs at most.

 

[GNVenom]

You don't need to swap the ignition module. The only thing you need to add is a MAT sensor and its wiring. The hot air cars are a bit less tolerant to mid and high range timing, so when using an 87 spec chip, be sure to reduce timing in those areas...and lower the boost as well. Unless you install an intercooler, the elevated inlet temperatures will make your engine more prone to detonation than the intercooled counterpart.
Ignition conversion: If you are going to convert to 87 style CCCI ignition, be sure to remove the resistance wire in the harness that feeds the coil pack from the bulkhead, otherwise, your 87 style ignition will be less efficient than the 85 style.
-John Spina

 

[WFO]

http://www.gnttype.org/techarea/ecmsensors/8487ecm.html

All the info you need is there...

Hey John,I take it your adapters eliminate the unwanted wire?That's the first I've heard of that,I actually cut/spliced my harness to swap to type II according to the gnttype article.Have you had a look at that article to see if the bad wire is eliminated?

BTW,thanx for dropping in on us hotair guys,your help is always appreciated .

 

[NOKA72]

yes i have to say this is the first i heard of that also...can you tell us more please.....vinny

 

[GNVenom]

To read more about the CCCI, go to this forum:

http://forum.casperselectronics.com/forum/index.php?showtopic=103

It's also in the FYI section of the forum.

-John

 

[tim sewald]

cost

How much does it cost to make this swap?

 

[GNVenom]

To do the complete ignition conversion for the CCCI:

Caspers Part Numbers and pricing available at www.casperselectronics.com

102085 Base Plate
102086 Plug-in Adapter
107125 Delco Module
107128 High Output Coil Pack

To convert the1984/1985 turbo car to 1987 ECM:

1227148 ECM (available from GM or other sources)
25007866 MAF sensor (Not available from GM - aftermarket or reman available)
107127 MAT (Airtemp) Sensor
102165 MAT Installation Harness

The MAF sensors differ in calibration between the years although I have heard that the 85 version will work OK. I have not tested that combination though.

-John

 

[Daniel Jost]

I have a huge problem here, i went out to work on my car tonight to get it ready to put an 87 ECM in it, and get this nothing even matched close on the colors of what they are supposed to be in the connectors, am i looking at something wrong because i am missing some of the wires that were supposed to be there. I noticed that the ECM that is in the car is a reman and what is said on the sticker is this:
Number: 7-6469
Calibration Code: 0996IM
is htis even the right computer for my car. The reason i say this is because the previous owner of my car a chip custom burned for the computer from casper's electronics and when i put it in it is running very very rich to the point that it hesitates. but when i put the normal chip back in the car it runs fine.

Does anyone have any ideas?????

 

[Squid4life]

Daniel, did you ever get your car converted over to 87 ECM? I just did it myself the other day. Not too bad. Let me know how it turned out, and if you found the right 'puter.

Squid

 

[Daniel Jost]

i never got around to completely getting the the setup in, i still need a computer and i have recently located some of the wires that i need. do you think you could take some close up picks of the wiring harness so i can see the arrangement. if you cant could you somehow send me the diagram that you went off of, or if you can do both it would really help

Thanks,dan

 

[Squid4life]

I am heading off to work, but will get that done today if possible. All I did was follow the instructions that WFO posted:

http://www.gnttype.org/techarea/ecmsensors/8487ecm.html

And it was very, very simple to do. When they start talking about the harness: (D-12, C-11)

"I ran the wire to the ECM under the dash carefully staying away from the gas and brake pedals. The MAT uses the same sensor ground as the TPS and CTS ,so I spliced into the ground wire at the ECM (D-12 black,no stripe). The other wire from the MAT sensor needs to be plugged into pin #C-11 (tan) at the ECM, this is where the wire from the other car came into play. It should still have the clip on the end that will plug straight into C-11 on the ECM plug."

I could not tell what was C or D, or anything. Pull the grey plastic wire retainers off (they poke down into the harness, alongside the wires) and look on top of the connector where the wires are. They are labeled in very small lettering. The C-11 is vacant, so no problems there. The D-12 you have to tap into. I stripped some wire insulation off about 4 inches from the harness and soldered and heat shrinked the "joint".

On the MAT sensor wire from the sensor in the air cleaner, or pipe, I cut the original wiring harness of the junkyard car as close the the harness as possible, and pulled four or five pins with wiring from the ECM. The I soldered and heat shrinked the joint as well, one in the engine compartment at the MAT, on at the ECM.

Probably sounds confusing but once you are reading the instruction WHILE looking at the ECM, it is pretty simple.

If you get stuck while you are doing it and I am at home, I'll give you my number and I can be looking at mine while you are doing yours. Let me know. I'll try to get some pics tonight.

Squid

 

[Daniel Jost]

you've been alot of help so far. as i type im calling around for a computer and sensor, from the local scrap yards. I have noticed the A,B,C, and D wires but, my instructions went of of wire number like #432,#345,ext.... any help is highly apreciated.
maybe if i could get some simpler instructions, but a little tie up wont stop me. after i just put all this money into building the motor.

Thanks, Dan Jost

 

[Squid4life]

lemme try this

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[Squid4life]

Nope guess not. Thought I knew how to post a pic. I will email them to you.

First off, I am not sure where your instructions came from, but use the ones from GNTTYPE.ORG listed above. They are very easy.

The MAT sensor is very easy to find at a salvage. Many, many cars made by buick, chevy, olds, and pontiac used the same one. I pulled the sensor, plug for the sensor, as much wire for the plug, and they even let me break apart (literally) an air box to get the brass threads that the MAT screws into. So now when I mounted my MAT in the bottom of my K&N, I used the plastic round piece with the brass threads in it, and epoxied it into place. So if I clean my filter, or need to change MAT sensors, I can unscrew it. I'd hate to permanently mount just the sensor and not be able to remove it.

The wiring for the MAT is two wires, obviously one being ground. But this can not be just chassis ground. It goes to the ECM and you have to splice it into pin D-12. This pin is on the opposite side as the metal clip that holds the plug into the ECM, and the gray comb looking wire retainer. I stripped a small 1/2" section of wire off about 4-6 inches from the plug at the ECM, meshed the ground from the MAT sensor to the D-12, and soldered them, them heatshrunk them.

Now the MAT sensor "signal" wire... What I did at the salvage was remove the gray comb looking wire retainer, at the ECM, and pulled a few pins out of an ECM. I cut the wires of a few of the removed wires/pins, making them as long as possible. One of these (I got spares in case I messed up) would be soldered to your wire coming from your MAT harness, and pressed into ECM connector slot C-11.

I know some people will have a fit about this, but my MAT ground and signal wire were soldered together from three pieces of wire each. MAT signal and ground from the plug at the air cleaner, a signal going to C-11, ground spliced to D-12. amd a length of wire in between to connect them. I could not figure out how to keep it a solid wire from the ECM to the MAT sensor. And if you solder, it shouldn't make a difference.

I have pics, to explain this a little better. Give me your email.

Or post back quick and I'll give you my # and we can figure it out.

 

[Squid4life]

And to reply to your statement:

"but a little tie up wont stop me. after i just put all this money into building the motor."

That's the spirit!!! I am having issues with my 85 GN that I have only driven 90 miles since I owned it. Lots of isssues to work out, but I'm getting there with the help of the guys on this page.

For a little motivation... My car runs like SH#$ above 3000 rpm but when I would take it for a test drive thinking I fixed it, I ease into it, leaving it in first gear, put steady throttle to it and the tires just want to spin. Not hard on the throttle, no boost, not from a dead stop shocking the tires, but just easing into it and feeling the torque of a new motor push those 3.42's and have the tires fight for traction. Was a great feeling, and I cannot wait for it to run right so I can get on it all the way and see what it'll do. It makes all these headaches worth it!

Let me know what you need brother.

Squid

 

[Daniel Jost]

Benefits
The following article describes how I updated my wiring harness and ECM to the newer '86-87 ECM. This update has several advantages over the original ECM such as:
Greater chip availability
The ability to use Tweaker to program you own chips
Twice the available data from TurboLink (R) in Road Mode
The ability to use BST-001 Boost sensing option for TurboLink (R)
1227148 ECM's are readily available in the "yards"
Electric fan control available (Optional)
I'm sure there are more reasons to change to the newer ECM, but these are the major reasons, feel free to think up your own too. <grin> I have recieved a lot of e-mail from people wondering if the car will run faster or get better ET's from the conversion. None of this will happen UNLESS it stems directly from the advantages listed above.

Limitations
A few things the ECM conversion won't do is to:
Make a poor running car run better
Fix a broken fuel pump
unplug a fuel filter
Repair bad injectors
Fix a bad TPS
Fix a bad CTS
unplug a plugged cat converter

The Conversion
After much testing, I must suggest that you also get a 86/87 MAF part #25007866. The calibration of the 84/5 MAF is different and gave drivability problems with the 1227148 ECM, when cold weather came upon us in St.Louis. The colder air sensed by the MAT richened up the fuel air ratio, trying to compensate for the denser air, to the point that the car would belch black smoke out of the exhaust. Switching to the 86/7 MAF cured the problem.

First off I went to the U-Pullit and got a wiring harness out of a FWD GM car with a '86-87 3.0-3.8 V-6 in it. When I removed the wiring harness, I removed the relays and sensors that were plugged into it too. Then I striped the harness down and dissected it wire by wire. This way, I got all the fan relays AND the MAT sensor w/plug and wire to the ECM. The wires at the ECM plug come out with a large paper clip (or jewlers screwdriver) inserted into the release hole. If you have never had a wire out of the ECM plug before, I suggest a little practice on the OTHER harness first!

Before your car can be driven without the SES light on, the MAT sensor must be put in. I cut a hole in the bottom of the K&N right in front of the MAF sensor to sample the incoming air temperature. Then I took the sensor plug/wire and ran it to the ECM by poking thru the grommet on the speedometer cable. I use wire loom in the engine compartment to dress things up and make things look factory. I ran the wire to the ECM under the dash carefully staying away from the gas and brake pedals. The MAT uses the same sensor ground as the TPS and CTS ,so I spliced into the ground wire at the ECM (D-12 black,no stripe). The other wire from the MAT sensor needs to be plugged into pin #C-11 (tan) at the ECM, this is where the wire from the other car came into play. It should still have the clip on the end that will plug straight into C-11 on the ECM plug.

The ECM can come out of a 86 century but be sure to have the part #1227148 ECM. The dealer gave me two part #'s for the cal-pak in the ECM, they are 16036503 and 16036504. My 84 ECM HAD the 16036504 in it so I used it.

Pitch any other cal-pak with a different number. I downloaded a ROM file from the archives for the prom. Any 86-7 chip should do. Use a stocker to get things going. But with the addition of the MAT sensor,and the chips to the ECM, this will plug straight in and run.(without the MAT sensor)
As far as the electric fan setup goes,This IS an option. The fan control at the ECM is pin #D-2. This circuit grounds a relay when active. There are many ways to wire and electric fan. So I will not go into too much on it right now. I wired up the 10 min timer to come on if the car shuts off and the temp sensor in the radiator is tripped(about 195 deg) with the fan on high. The fan also runs on hi when the ECM calls for it. I have the low speed coming on with the A/C. To get more acquainted with the fan circuit (and ECM).

I went to the library and looked up all the different years in the Mitchell manual. Take a bunch of dimes and copy the pages that you are interested in, like the ECM pinout and the fan setup on several cars. I found some pusher/puller fan setups too.

As you should always do when splicing/adding wires. I use a 150 watt or so soldering gun and rosin core electrical solder to solder ANY connections you make. There is nothing more frustrating than looking for an electrical "gremlin" than to find out that YOU were the cause of it by not doing it right the first time. Get the wire good and hot so the solder can flow into it.

Also use HEAT SHRINK! Tape tends to come loose and fall off over a period of time, and get "gooey".

At the ECM , taking the wire out of the plug , stripping a small area bare a couple of inches from the plug and solder the wires together. Then, slip on the heat shrink, and make sure it shrinks good.

By following my procedures outlined here, the ECM can be changed (less fan circuit) in about 30 minutes if you have all the stuff already.


this is all i see i dont have any pinouts... were am I supposed to go for all the pinouts for the whole conversion not just the MAT sensor, and electric fan. or am i just dumb and im missing something

did your car run bad after this conversion, or before also?

Also my E-Mail is "dan@wastedincome.com"

Thanks

 

[Daniel Jost]

hold on.... reading this thing over and over numerous times, think i figuered it out. it doesnt need to actually be completely rewired only the mat has to be wired in, and some splicing.

but what is a cal-pack is that the smaller chip?

 

[Squid4life]

You've got it. No rewiring, only adding one pin, then splicing into the ground wire. Cal pack is the smaller chip.

Let me know if you need pics later.