Edit: I have a 93 Deville ECM controlling my 94 4.9L/4T60E (with the proper sensor and tranny wire corrections)

I just bought a scanner that does both OBD2 and OBD1 and when I connect it to my 88 4.9 Fiero, and turn the
key to the ON position, I get a "Vehicle not responding...". I checked the connections and I also checked the
scanner on a different car (although it was an OBD2 car) and everything is fine on that front.

So, now it's time to look into the Fiero wiring.

In the diagram below:
1) I'm assuming that we're looking at the ALDL connector as though it is mounted in the factory postion and
we are sitting on the dashboard. Is that correct?
2) I checked the A8, ground, and E12 connectors that they all have continuity at the ECM positions, but I
don't know where the "fuel pump" connector should be reading from. There is a "fuel pump feedback"
pin on E13 of the ECM, and there is "fuel pump relay" pin on F1. Are either of those the "checkpoint"
for checking what "fuel pump" signal the ALDL is getting?

thanks,
-Tim



Edit: I just noticed on the diagrams I have for a 91-93 Deville (and on the
schematics in the first post as well) it shows on the ALDL that
A position connects to GND
B position connects to E12
M & L positions connect to A8 which also goes to DERM (whatever that is)

[This message has been edited by BigGuyTinyCar (edited 04-08-2011).]

quote Originally posted by Fieroseverywhere: The fuel pump circuit is for manualy priming the pump (connect +12v to that pin). Unless someone put it in there for your 4.9 swap it probably doesn't have one. Especially if they used the caddy ALDL connector and/or the caddy fuel pump relay. E12 is used for setting the timing. A8 is for scanner data (I wired it to both pins M & L). A is... obvious.

Thanks. Mine appears to be wired correctly, but it won't communicate with my scanner for some reason.
It doesn't appear to be a scanner connection problem because it says, "Link Initialization established", but
then quickly comes back with "Vehicle not responding". What the heck is DERM?

[This message has been edited by BigGuyTinyCar (edited 04-09-2011).]

quote Originally posted by BigGuyTinyCar: What the heck is DERM?

DERM - Diagnostic energy reserve module. In particular this device is part of the SIR, or supplemental inflatable restraint system. One function of it is... In the event of a front end crash where voltage is lost the DERM will make sure the airbags can still function. This is done by way of a 36 volt reserve loop. The DERM can also detect malfunctions in the SIR system, record malfunctions, notify driver of malfunction (by way of a "inflatable restraint" light), or record system status during a frontal crash.

Obviously not necissary unless you installed airbags in your fiero.

[This message has been edited by Fieroseverywhere (edited 04-09-2011).]

[This message has been edited by hookdonspeed (edited 06-15-2011).]

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, 3.4" Pulley, N* TB, LS1 MAF, Flotech Exhaust Autolite 104's Custom CAI 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

quote Originally posted by Dennis LaGrua: I thoroughly enjoyed reading this thread and was inspired to do a 4.9L swap. Lots of great info posted here. Ho0wever these Caddy engines seem to be getting hard to find in solid shape. Sure you can get the 130K+ powertrains but try to get one at 80K or less and your are S.O.L. I've been looking for quite some time with out success. Maybe I'll get lucky and find a recent low miles wreck but that takes me back to the 3800's that appear to be available.

I wouldn't worry about 130k - I have found through experience that these things are fairly bullet proof. That being said, if you are still on the fence I would probably lean more towards the 3800SC (power and revs are better) - but you need to decide on which side of the fence you want to be on.

quote Originally posted by olejoedad: I have a question concerning the pinouts and diagrams - Per Schematic M66006-8D1-C-1 (on the first page of this thread), ECU grounds are D1, D5, D7 and A12 - BUT per the MetriPak pinout for connector C/D, ECU grounds are located at D1, D6, D7. My C/D connector has D1, D6 and D7 as grounds. Should I leave the connector the same (D6) or re-pin it for D5 as the schematic indicates? Stickpony reprogrammed the ECU. Thanks for the input.

Which ECM are you using and what did Stickpony program for?

The diagrams are for a 91 Deville setup - other models and years vary. So if you are using the 2240 ECM and have the EPROM programmed as the 91 Deville use the diagrams as posted - otherwise you will need to make the changes to match your setup.

[This message has been edited by Mickey_Moose (edited 08-16-2011).]

[This message has been edited by Fieroseverywhere (edited 08-16-2011).]