1983 Mercury Grand Marquis 2Dr "Mercules”

[Mainemantom]

Took me 8 months to find it. 25 bucks shipped!

The seller did not know or care what he had. You got a good deal.

[Grand Marquis GT]

Oh, and I have a new steering wheel.

[Grand Marquis GT]

Thanks everyone for voting me at POTM! So, I woke the beast for the spring/summer, after fixing a roached coolant hose and charged the battery. I picked up some of this rust encapsulator from the local parts guys, and painted it on. This of course was after a session with the grinder/cup wheel. This seam was starting to worry me, as it Is where the sides of the bulkhead are leaking due to rot. Can't wait to fix that soon (sarcasm). I also replaced a missing lugnut, and cleaned it up a bit (but not too much).

Took a 25-30 min drive, including some 80mph cruising down the interstate (gotta love Texas speed limits!) and it performed about as well as EEC-III CFI will. She's a gutless wonder!

[SVT98t]

Get some!!!!


-ryan s.

[Grand Marquis GT]

Went to Pick N Pull (Dallas West) yesterday. Harvested a complete 88 wiring harness, dostributor, and the complete intake.

Want to take a guess what I am going to be doing?

[Kodachrome Wolf]

Went to Pick N Pull (Dallas West) yesterday. Harvested a complete 88 wiring harness, dostributor, and the complete intake.

Want to take a guess what I am going to be doing?

Swapping from CFI to SEFI? And I would assume you're also going from a Duraspark setup to the TFI module?

[Grand Marquis GT]

Correct. Some neanderthal butchered the wiring where the relay connectors were supposed to be, but that looks like a somewhat easy fix. I have been analyzing the wiring diagrams from 88 and 83 and it doesn't look like much has changed.

[His Royal Ghostliness]

Enough has changed to annoy the hell outta you tho.

Chop the square connector for the '83 trans harness off the one that runs along the cowl, splice the 4-wire grey connector for the '88 harness into the '83 wiring that runs alongside the cowl, you'll be using only three of the four '83 wires, remove the red/blue one as it is all stupidly connected and you have the proper one contained into your SEFI harness anyways. Then plug the entire '88 trans harness into both the SEFI harness and the newly spliced connector. This is the straight-forward part.

Remove all wiring that operates your A/C, new wires are contained into your SEFI harness, you get the nice feature of A/C compressor cutoff during WOT conditions (it helps). The only wire you'll end up with is a piece of black wire with yellow (hashed) tracer coming out of the firewall, splice that into the green/purple wire of the big round 4-pin black SEFI connector in the ECM vicinity, that's what makes the A/C mess do what it needs to do. In the same connector fat orange wire is your fuel pump power off the relay, splice that into the '83 fat tan wire with black hashed stripes from that funny looking 4-pin brocn connector (again in the ECM vicinity).

And so on and so forth. Some wire colors will match, most will not, and you'll be splitting the wires from one SEFI connector into multiple '83 connectors and harness branches. Then you'll find out some of the SEFI wires have no equivalent in the '83 harnesses anywhere. For example, your new heated O2 sensors do not have a power supply in the CFI harness, you gotta provide them with one yourself. Make sure you have plenty of steaks to throw on the grill, you'll need them to calm your nerves down. lol

[86VickyLX]

Luckily, you don't have to really worry about the trans harness too much. As you have the manual swap. But having it all self contained in one harness will be easier for diagnostic purposes!

[packman]

Went to Pick N Pull (Dallas West) yesterday. Harvested a complete 88 wiring harness, dostributor, and the complete intake.

Want to take a guess what I am going to be doing?

Modify it and Coyote Swap Time!!!! LOL

It amazes me the kind of wiring fixes people do to keep things running. Somebody had the bright idea of Perma-texing my injector connectors after snapping the plastic clips off of them. Had to replace each connector :-/ Baffles me why anybody would go through the trouble of using Permatex when Home Depot sells duct tape at decent prices?

[Grand Marquis GT]

Next week Instart the nasty job of cleaning all these parts up. Should be fun.

I also need to get some electrical contact cleaner and start going through the harness.

[Grand Marquis GT]

In six weeks when I am all healed up from surgery, work begins again.

EFI swap, wheels/tires, and going from there.

[Giraffe]

Looking forward to seeing some progress. She looked pretty nice in person!

[Grand Marquis GT]

So, I scored some wheels. I rolled one up to the car to see how it’d look.

With 235/50R18s tucked into there (already have the 1.5” spacers) it will look perfect!

[gadget73]

Looks good