Need EEC pinout for 1990 Lincoln Town Car

[Lincolnmania]

dont use the 91-93 mn12 ecm, it will run too lean.......blaze burned a hole in a piston yrs ago

[Crownvicman289]

No 5.0 MN12's at the yard like I thought there were. Does anyone know what the data bus does on the EEC-IV's? The SN95 and MN12 both have data bus wires and my car has data bus wires. They're separate from pin 34 which is the fuel flow wire for the mpg indicator. The data bus is what makes me want the MN12 EEC. I need to look into whether or not it can be tuned also. That MKVII EEC is starting to look yummy again. I bailed on the SN95 even though I have one because it lacks that fuel flow output. An A9anything would work, but one hasn't yet shown up at the local pull and steal to try out. I know it lacks the data bus wires and at this point that's my only concern with the A9 series. I found some testimonials where people used the larger SN95/Crown Vic MAF's on the A9's and the cars ran great. Of course none of them used a wideband to confirm. As of right now, I started going after the harness and setting it up for an 87 HO Mustang.

[gadget73]

data bus might be output to a fancy pants scanner that can read the various sensors in realtime, kinda like obd2 can.

[Crownvicman289]

It's 2 wires kinda twisted together. It leads to the normal EEC test port and splices and runs into the car as well. That's the one that bugs the living crap out of me. As long as it's not telling my bells and whistles inside the car how to act then I couldn't care less about it. That's really all I give a crap about, I can't wait to see that info center telling me my mpg again. I've had all the soldering fun I can stand tonight, mainly because I ran out. I'll finish tomorrow as I'm about 3/4 of the way done. I installed 2 10k 1/2 watt resistors in parallel with the TAB and TAD leads to the EEC in hopes of faking it out so it doesn't throw codes. I've got 6 wires to solder to the harnesses that lead to the fender, I need to snag a start wire for the TFI and EEC, and I need to solder the EGR valve position sensor and vacuum control valve back into the harness. Then I can tape it up and make it look pretty, get the upper intake on, and see about getting it fired up. I want to have fun next weekend instead of pillaging the junkyards and wrenching!

[bigblackmariah]

it's not the heat, it's the stupidity

oh god, every time i think i have it, i read another thread and get lost. what de heel is a TFI module? that ignorance being brought to light, could your 34 PIN be an input/output for the M12's suspension/steering/BCM gem control module?

[gadget73]

TFI = Thick Film Ignition. Its the grey thing on the side of the distributor for stock cars, or the black thing mounted on a heatsink somewhere else on 94-95 Mustangs and the 92-93 Couger and Tbird.

pin 34 is fuel flow output for the tripminder or digital message center so it can calculate instant fuel economy.

[Crownvicman289]

No, it's fuel flow output. It's the same on the 4.6 EEC also. The car runs and idles now, haven't gotten the throttle cables hooked up yet, but it idles nice and stinks a lot less!

[gadget73]

running with the EFI on? sweet.

[Crownvicman289]

Yep, throttle cable's hooked up now. I'm leaving the cruise out until I decide I didn't fuck up any wiring, it's in the way of all that. I did forget my tach wire though, so the harness will come out again for that when I get back from the desert. I just need a longer belt for the 3G as its housing won't allow the alternator to rock inward enough to get the existing like-new belt on. Once I decide the coolant leaks are gone, I can bolt up the AC bracket that holds the coil and I think I'm done. One thing that throws me is there is in fact a pin 34 on the DA1 SD EEC that I'm using. The other blanks were blank, but there was a conductor leading somewhere on the circuit board for 34 so I've got my fingers crossed. . . OTOH, my CEL doesn't work and I've got to wonder if it doesn't have something to do with that damn data bus. If so, the only answer is an MN12 EEC and a quarterhorse.

[gadget73]

I doubt it. The CEL goes to pin 17, same as the STO wire in the self-test connector. Its that way on every ecm as far as I know. All I had to do with the Grand Marq is find the wire in the harness and tie it in. Could be the bulb is burned out. I want to say that grounding it with the key on should make the lamp come on. Might just the bulb died.

[Crownvicman289]

It was on all the time when it was carbed, so I know that the bulb is still good. I just hooked pin 17 STO/MIL to whatever pin the 4.6 used for the same function. I expected the light to come on with key on/engine off but it doesn't. At first I was pumped with the engine running and no CEL, then I realized it appears to not be working. I'll try pulling codes and see what happens. Is there a code it throws for "all is well" or if there are none will it stay blank? I know I can do it from under the hood as well.

[gadget73]

11 is all's well during a self-test. I'd bet you'll get codes though, but most of them don't actually trip the light. EGR related crap turns it on, but not much else seems to. without a smog pump, expect at least a 44 and 94.


CEL was on with the carb? Not sure how that should even be if the EFI harness was gone. It shouldn't have had a connection to anything with no harness in place.

[Crownvicman289]

No air pump, but I did install 2 10k resistors in parallel and soldered the TAB and TAD wires to them in hopes of faking the EEC into not giving me codes on that. The EGR is legitimately hooked up so I'm hoping no codes there. O2's are installed as well. Reason CEL was on before is because the EEC was still installed in the car and though the EFI harness wasn't there, everything that tied back into the car was still there. I'd entertained the notion of pulling codes when carb'd but that'd be a lot of work for a laugh.

[gadget73]

you wont get codes about the solenoids not being present, you'll get the 44 and 94 because the o2 sensors won't see air being introduced to the back of the heads during the self-test. It doesn't set a check engine light though and it won't store those codes.

[Crownvicman289]

KOEO code 85 - EVP fell below .24V
CM code 31 - EVP circuitry failure

Woo hoo! That was it, and my CEL DOES work! Fuckin eh right, purge can isn't yet installed so that's the reason for those codes. I'm hoping to install a '98+ out back. Took it for a drive and it pulls a bit harder than it did with the carb. Getting it moving from a dead stop is a lot less of a chore as well, you'd never know it had an aluminum flywheel now. I think the wife could handle driving this now. After I fix my boo boo that is. . .

On another note, since I run an underdrive crank pulley, the old alternator put out 13.5V at an idle with nothing on, save for maybe the radio. With the power of 3G, it now puts out 14.6 at an idle so I'm thinking my headlights won't dim every time I push the clutch in now. And my tripminder/econogauge works with the old SD EEC! So does my factory digital temp gauge! If only I was this good when I first pulled the swap off 9 years ago!