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Discussion Starter · #1 ·
I have a 2000 GT with an automatic and 105k miles. I never had an issue until this morning, when I started it up the O/D light was flashing. It eventually went off and I began to drive. The car somewhat hesitated and the RPM would jump about 200 RPM. I was able to get it home with the RPM constantly jumping up 200 and then back down. The check engine light eventually came on as well.

I checked the fluid and it all is good there. Next, I tried to scan for codes, but it says it has none...which has me stumped since the two lights are obviously on. Just got off working midnights so I need to go to bed before seeing if Autozone can scan it better than my handheld one. I did an online search of course and it seemed replies were all over the place, but I did not see anyone mentioning the RPM jump, so I was hoping someone here might have experienced something similar.

Thanks!
 

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Discussion Starter · #2 ·
Ok, I finally got some codes...it was P1747 and P0743, which are two of the three solenoids in the trans. I replaced all three with new OEM ones and I am still having the issue. One search said I might need to have my PCM reflashed. Does this sound correct or has anyone else had a similar issue and needed a reflash after replacing the solenoids?
 

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Discussion Starter · #3 ·
Bought and used Forscan and pulled codes P1760, P1747, and P0743. I cleared all the codes and drove around a little bit. Shifts are still sloppy and I still have the 200 rpm surge when cruising. I then had code P0743 and the OD light and CEL were no longer on. Next, I am going to try replacing the transmission speed sensor as I read that can cause the issues I am having. The tread mentioned the odometer going out as a sign of a bad speed sensor, and I have been having that issue for the last month or so.
 

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Discussion Starter · #4 ·
Well, the new speed sensor from American Muscle arrived and of course my luck it doesn't fit...even though the website says it will. CJ Pony parts had it but with shipping, it was over $50, so I ran to the local parts store and it will be here Wednesday for half the price. AM at least told me to keep it and refunded me my money so I am only out shipping costs.

Also, the OEM part number is F4AP-7H103-AA and is obsolete from Ford. Below is a pic of the original and the one AM website is the replacement. (The one on the right is OEM.)

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Discussion Starter · #5 ·
Well, the correct speed sensor came in...and it did not fix my issue. I have attached a picture of all the codes Forscan picks up. Reading up it said to check the wiring and connectors and all see in good shape. The next thing is replacing the PCM, but I hate to drop $200 if it does not fix it.


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Discussion Starter · #6 ·
Well, I have thrown the towel in and I made an appointment with a local speed shop. I chased down all the wires and connections. I blew them out and cleaned where I could. My last thought is the PCM, but before I drop that coin, I will let them look at it.

So I have had no responses, but I wanted to keep updating incase anyone comes across this issue. I will come back and update this thread once I get it figured out.
 

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When you changed the solenoids, you should have changed the internal harness, they are known for going bad. Your PCM should be fine especially since you are still getting codes. You have checked the external harness as well. FYI there was a recall on the internal harness back in the day.
 
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