1995 Mustang Ignition Problems (solved)

[Darren5.0L]

During the summer of 2006 I had just removed my car from long term storage (10 months) and was poking around under the hood doing the normal inspection of things. I discovered a burned plug wire, so to solve this I put on a new set of MSD wires ($120) and considered it a done deal.

A week later I started having a "misfire" kind of problem but attributed it to the car being a bit damp with the Ram-Air in the rain the night before.

I took the car out to Stratotech Raceway for the SVTOA’s annual Track Day session and experienced the same symptoms as before.
All through my time at the track I chased this problem which only got worse as the day went on. (lacked power about 3500RPM) I figured something was seriously up so I babied the car home and started troubleshooting.

I only had 1 day left to find it and came up empty handed, so I went back overseas a bit angry at my car.

Fast-forward to This August I get home and pick up where I left off, being irate at the car mostly and began the battery of tests.
All the sensors where within their range, MAF/TPS/IAT/ECT O2's etc. (Thanks TwEECer R/T)

Further driving found this would only happen when it was hot, but it was becoming increasingly easy to make this symptom occur.
A
check of the coil revealed that my MSD Blaster had broken free of it's housing and leaked out it's oil filling. It was replaced with the stocker and later a Crane Fireball, ($60) this cured some of the high RPM problems but the low end stuff still remained with a vengeance.

I replaced the TFI module, ($60 Accel HO Unit) checked the plugs, cap and rotor, and even sent datalogs of the behaviour to fellow TwEECer users to come up with everything appearing normal.

I even replaced the CCRM ($250) (computer control relay module) which are known to burn up in these cars as they are mounted essentially to the front of the motor. (fan shroud)
Still the problem remained.

I replaced the fuel pump with a 255 lph ($160) unit figuring that perhaps my problem was fuel related, and not spark as I had all new components in that department. The 255 pump went in quite quickly and did not cure my driveability issues, I had also installed an Oil filled type fuel pressure gauge on the rail to help let me know what was going on with the fuel system.

After driving the car around and getting it warm, the gauge was telling me the fuel pressure was dropping to 15 psi, so I figured the Fuel Pressure regulator was bad. I replaced it with an adjustable Aeromotive unit.
After getting warm now the pressure would still drop but only to 24 psi, after tinkering with the fuel pressure setting at cold, then hot, and a happy medium. I found nothing would cure the drop in pressure.

On a total whim I decided that perhaps my brand new wires were the problem and replaced them with my burned (but known to work) Ford Racing ones. Upon pulling the boot protectors off the new MSD wires (1300km's on them) to transfer to the Ford ones I noticed the #7 plug wire was crumbling, I checked the boot to find it had burned right to the core and the boot protectors had covered this from view.
After putting the Ford wires on the problem went away, period.

But the fuel pressure was still dropping at an alarming rate when it was hot, but the car ran so well, that I began to suspect the gauge was faulty. I replaced it with an air-filled Auto-gage by Autometer and instantly the fuel pressure was back at normal.

A few weeks later the car lost all spark and wouldn’t start, so I had to troubleshoot that further.

I went out the next afternoon to start working and it fired up on the first flick of the key, very annoying.

As I was driving it home it stalled twice at 110km/h cruising, I dropped it in second and popped the clutch and it would fire and run again.
I got it home, parked it, and tried to start it again, it would not. This was good as I could now trouble shoot the system.
I swapped in my 2 other TFI modules and coil to have the same result. So next I went to check the distributor, but did not have a test light on hand.
I took off to pick one up and when I returned, the car started just fine, keeping me from troubleshooting.

With the Radium cruise only mere days away, I decided to just throw another part at it and hope for the best. I ordered a rebuilt distributor ($90) and paid air freight to have in the next day. I "borrowed" timing light and had the change made in short order, we timed it up to the factory 10* it fired on the first try.

I shut it off and started it a number of times and everything worked. I plugged the TwEECer back in, selected my Cobra tune, and tried it again, no problems.

I put a full tank of fuel trough the car in 2 days of city driving and declared the car ready to go. After driving over 1300kms on the weekend, and none of them easy, I assume my problem is cured and I can get back to modding it.

[The Fox Master]

I'd be willing to bet it was the pick up in the distributor. They are replacable and when I was ford tech (pre-apprentice) we were told to always replace the pick up whenever replacing the TFI as one can effect the other. It's an oft overlooked part, especically when the TFI module solves the problem, then some time later the problem returns.

Sounds like your new distributor fixed you up, what a shame you had to spend so much to diagnose it!

I've had no luck with MSD ignition, but thier wires have always been decent for me.

[Darren5.0L]

Revived for use.