Progress Thread Nasty Ninety Notch

If that car was mine I would've fixed it already, with a Molotov cocktail!!! I hope this ends your gremlins.
Tell me about it! I was in too deep a long time ago though. The only gremlin I know of right now is the cruise control.

We fixed the sway bar hitting the drain plug problem and end link geometry with one part. We used a Steeda 03-04 sway bar spacer. It moves the sway bar down about 3 inches to mis the drain plug and thus lessened the end link angle too. Its a sweet deal at $49. I'll get some pics tomorrow.
 
UPDATE: Test Drive & Trouble Codes

So I learned a few things about the Nasty Ninety Notch on a test drive today.

1) While taking a sharp on-ramp at a fast rate of speed the front end was GLUED to the road and exhibited no body roll at all (love the coil overs, etc). However, I did find the limit of the rear end as the tires started to chirp at me; so I let off. This is by far the best handling Mustang I've owned. It's very predictable now. The steering is effortless with 135lbs off the nose.

2) The smell of raw fuel upon cold start in the cabin required windows down. The smell is gone once the engine is warmed up, but will return when turning aggressively (see #1).

3) Many KOEO codes (22, 32, 51, 53, 54, 67, 96) so its not running at full strength. I hate codes.
 
UPDATE: Diagnostic Dynamite

Struck diagnostic gold again...
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After many diagnostic hours using this GOLDEN resource it was determined that our replacement ECM was shot. This was a good replacement ECM so we never thought to look at it until the end of the diagnostic period. In order to make a long story short, the problem was due to LATE MODEL RESTORATION part LRS-8793XSHM (1987-93 FORD MUSTANG O2 SENSOR HARNESS, MANUAL TRANSMISSION - FOX BODY).

One of the "Benefits" of the part is supposed to be "Plug & Play Install." In reality, its more like Plug & Pay More Install because this product WILL fry your ECM. Our harness came jumpered for an automatic. Therefore, as soon as we plugged it in and turned the ignition key it fried the ECM. Yes, the car still ran, but it was sluggish and had several trouble codes that led us on a wild goose chase. Eventually our tech traced the trouble back to pin #48 and a 3mm long burn inside the ECM. That's stinkin A+ diagnostic work!

Once the tech found the burned out pin #48 he researched possible causes with the manual above and the good old internet. While on the net, thank the Lord, he found a pdf about another guy having the same problem (wrong O2 harness). After reviewing the pdf he was able to make the needed repairs and I got to buy ANOTHER ECM. Thanks Late Model Restoration (sarcasm)! Do you know how hard it is to find an A9L processor these day? They are expensive now too. Thanks again Late Model Restoration (sarcasm). I wonder if they will foot the bill for a new ECM since there product was not "Plug & Play," as advertised?

In the interest of helping others, below is the attached article (pdf) on the problem and how to avoid it.

Since the resolution I have put about 150 miles on the car (300 since rebuild). It has an erratic idle at the moment so we are going to perform a base idle reset with TPS re-adjust and go from there. It is also believed that there may be a slight vacuum leak due to a high pitched whistle from the engine bay as well as no cruise control (all elec checks out fine in cruise circuit). Updates and more pics on the way...
 

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UPDATE: Driveability

So the erratic idle seems to have been solved by tightening the upper intake (plenum) tighter. The bolts were too loose. This also seems to have eliminated the high pitch whistle too. We will drive it more to verify again. Yes!

Next up, on Wednesday we will plug in the cruise control module now that there is a new ECM and see how that works. Lastly, the A/C will get a proper charging and will be verified at that point. This may be the last of the mess. We may be giving birth to this car after almost 9 months in the shop. Stay tuned...
 
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Update: Dark & Gassy.

Went for another test drive tonight. Filled up with gas and got a large raw gas smell in the cabin. Had to put the windows down to breath. Its not the gas cap cause its a new FMS unit. Gassy...

On the way home from the gas station the instrument panel went dark with the lights on. By the time I got home the gauges were all messed up and the hazards were lit up even though they weren't on. Dark...

Now, I have no idea whats going on because the instrument panel is being ridiculous. Not sure what's up. We just replaced the instrument panel regulator yesterday.

Lastly, most of the vacuum leak is gone, but there is still a little leak that manifests when the car is at operating temp.

Never ending story, anyone?
 
UPDATE: Instrumental Repairs

Ok, so the vacuum leaks are fixed. No more whistling and erratic idle. We removed the plenum and re-torqued the lower for good measure.Then, we re-tightened (not torqued) the plenum. Problem solved.

The raw gas smell is coming from the O-ring area of the fuel level sender. Either the O-ring is leaking, or it wasn't installed correctly. Either way the tank is being dropped to handle the problem.

Lastly, we apparently fix 25 year old instrument panels too. Our tech Jay seems to really like figuring out electrical issues (I know, its odd).

The printed circuit was raised up in many places. That had to be fixed with solder and glue.
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The worst area was this raised up plug in port. If you look at the middle copper strip it is shorter than the others. That's because it had broken off at some point in time. That area was most likely causing all the problems. Jay fixed it by soldering in some strips of speaker wire (in a flat arrangement). The panel now works like new!
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UPDATE: Acceleration

The Nasty Ninety went out for its first throttle pounding today. I learned a few things:

1) It's stinkin' fast. Usually when a performance car accelerates the passenger gets pinned to the seat. However, in this test, I (the driver) got pinned to the seat...until about 75mph when I let off. Furthermore, I let off because of traffic. The car seemed to have no drop off of power at any RPM or MPH. This car is substantially faster than my 95 351W conversion. I was surprised.

2) The car grabs traction WELL. It seems that the torque box reinforcements, up/low control arms, diff side poly bushings, sub-frames, and rebuild Trac-Loc make for a good suspension after all. The 135lbs off the nose probably doesn't hurt either.

3) That acceleration, again. It's quite visceral. It has a nice raw and brutal feel to it. It is enough to cause old clamps to fail (lol). The TB clamp and an intake tube clamp backed off during acceleration. They must be replaced.

4) The 1st on ramp was straight, the 2nd on ramp had a curve followed by a sharper curve (CA, I know). This gave me an opportunity to see what cornering ability the car has. I was shocked that without a panhard bar the car was superb in tight turns. I took the on ramp at almost highway speeds (i.e., about 3/4 highway speeds). Body roll was non-existent during the maneuver. Rails for sure.

So far it seems that the car has a real nice balance to it all the way around. The last mechanical issues seem to be fixing that gas leak, refilling the A/C, and replacing some clamps. Then, hopefully, stage 2 & 3 begin. Stay tuned...
 
UPDATE: Cool ride, in Technicolor.

We got the A/C working! Also, when the gas tank was full I noticed that there was a raw gas smell in the cabin. So, we pulled the tank and resealed everything which took care of the issue.
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Lastly, the car is off to the body shop for some much needed love. So, what color do yall think its going to be? Here's a hint: its bold and its from the late 60s.
 
Dodge Challenger Green? Sounds like you had a really fun drive in the car. So if stage 2 is paint then what is stage 3? Boost?
Nadda on the color, but good guess. That is a bold color. However, the color will be a Ford color.

Stage 3 will be interior Lord willing. The car has 10:1 compression so I don't think boost would work well. And yes, the drive was fun. The car is intense.
 
Hopefully not grabber blue. I think most of the 60's colors don't look right on fox bodies. Probably due to the lack of chrome bumpers,trim,etc. I like those colors but....?