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SHO 97TR Wire Loom Failure

new 11/26/2003

Please add my story to the website if you deem appropriate.

I took my 97TR SHO with 75K miles in for service the beginning of last month to Woodfield Ford for the engine missing and stalling at idle. I would shut the car off, wait 5 minutes and it would run fine for a period of time.

After not being able to duplicate the problem as it was very sporadic, the mechanic Josh thought that the symptoms I described sounded like the IAC. He replaced it and it acted up, started missing and stalled at the first light I came to as soon pulled out of the dealership. The car was laid up one day this time.

I returned to the dealer the following week and after again running diagnostics and not being able to pinpoint the problem felt the next logical choice was the Mass Airflow Sensor. He thought that the oil residue from the K&N filter cause a short possibly in the MAS. He replaced that and the air filter to be sure and again I drove off. The car seemed a bit better but again the next day it started missing and stalling at stop lights. The car was laid up 2 days this time.

I took the car back again 2 weeks later as it was the first time I had gotten a chance to get the car there. This time I could reproduce the problem and I had the mechanic Josh and Tony the service manager in the car at the time of the miss fires and it stalling at a stop light. They again ran a massive battery of diagnostics with no clear errors. I then found the SHO No Go posting on the site about the bad coils causing similar symptom. I directed Josh to your website and had him run the tests per the posting. None of the coils came up bad. He switched the coils around to see if the miss moved with the coils but it did not. Next Ford technical recommended shielding some wires in the harness as there was a high voltage spike going to the MAS. Another possibility was a short or ground in the wiring going to the PCM. Josh started to peel back the flexible black insulation on the wiring harness and noted that some wire had already been shielded. On further inspection of the wiring at the firewall going into the PCM the wiring was badly burned and most of the insulation was gone from all the wiring going into the PCM connector.

Per the V8SHO website and some other postings on other sites it looks like my car was a victim of the surge tank being placed to low forcing the wiring down on the valve cover and making it deteriorate over time. After inspection there was no way to repair this other than going wire by wire and repairing and replacing the insulation, or replacing the wire loom. Either choice was expensive. After a long discussion with my mechanic, the service advisor, the service manager, the dealer manager and the customer service manager and Ford technical (incidentally the mechanic from Ford Technical admitted this was a problem with other SHO's and wiring had been burned in other cars) we decided it was best to replace the wire loom in it's entirety.

The part was ordered from Ford and Josh got to work replacing it and reconnecting all the plugs connector by connector. Once complete a couple days later, the car would not start at all. He was on the line with Ford Technical multiple times, replaced the PCM on their recommendation and finally got to someone who knew the SHO and told him the cam sensor wires were reversed and it's a defect in the new wiring harness. He switched the wires and the car started with no issues and ran fine. Ford sent out a correct harness, pulled the defective one out, put the good new one in and on my recommendation to be safe replaced all the coils.

Car now runs like a top. Car was laid up almost 3 weeks this time and 4200.00 later.

IAC - replaced - free
MAS - replaced -free
coils - all replaced - 100 each
PCM - replaced - free
harness - replaced - 2100.00
front rotors (unrelated to the issue but needed anyway) - 50 each no labor
labor total - 1100

I called Ford customer service and got the "your out of warranty, this has never been reported before and your car has too many miles on it to help you" story and would not reimburse me for any of the repairs, I know, the dealer knows, the mechanic knows AND Ford technical knows and admitted this was a known problem.

Woodfield Ford however did me right even though it was a heavy repair bill. They rented me a car at their expense for the duration. Gave me all parts at dealer cost, did not charge me for the PCM, took the IAC and the MAS off the final bill and only charged me a third of the true labor it took to get the car repaired and that they gave me at a reduced shop rate, put new front rotors on my car (I needed them), washed and hand waxed my car AND gave me a full tank on giving me the car back. The service manager even took it home for the weekend and drove it for 250 miles to make sure it was finally repaired before he would give me the car back. The "real" bill would have been over 6500.00. I have had nothing but a positive experience dealing with them and they did their utmost best to satisfy me and I would recommend them to anyone.

Now....off to Eric Lehmann on the 6th of Dec to have the cams welded.

Rich Carroll
97 TR


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