ECU SWAP from 850R to 850 T-5

Benford · Post by **Benford** » 26 Dec 2012, 12:18

Thanks all of you, my 97 T5 has been acting up, the small positive cable has been molding up, now the car is shifting strangely and my radio just coded? I do not know if it is just the ECU or the TCU (Transmission Control Unit?) I plan on replacing both to be sure. I also thought I would get some gains from the R ECU, but now I will stick with the original T5, I found both units used and will keep my old ones so that I can have them reflashed. So this brings me to new question how expensive is reflashing and would that fix my problems?

Post by **matthew1** » 26 Dec 2012, 12:24

Welcome to MVS. Flashing is solely for performance and won't fix any underlying problems. You'll have to check ARD's site for prices. But again, it will only cover up, or expose further, problems that already exist.

Sounds like your battery is dying. As for shifting, check fluid level and color.

Benford · Post by **Benford** » 26 Dec 2012, 12:41

Fluid color is good a bit over full. The car dies at idle in park and lurches while in gear. We live in southern Nevada now and the battery is less than two years old, but that is about battery life here. I am towing the car to Oregon on a dolly this weekend and will be repairing it there. It does have almost 200K miles on it, I purchased it from original owner, an elderly gent who took immaculate care of it, as do I. My 96 Turbo wagon has the same miles and runs like a champ, I did increase the boost on that turbo and that car is a bit quicker than the T5? You are persuading me that it is more than likely the transmission?

Post by **matthew1** » 26 Dec 2012, 13:39

I'm just throwing out ideas based on what you've said.

Any codes?

I'd go over the Stage 0 stuff and see if anything jumps out at you.

Benford · Post by **Benford** » 26 Dec 2012, 16:42

Thanks again Matthew1, I will take the car to a good Volvo shop and have it checked out, I already found a 97 T5 wagon that is being parted out with 178K miles on it. If it is transmission I will buy one and have it inspected/overhauled as needed. I will pick up the ECU and Trans CU. Plugs, wires, cap and rotor are all less than 20K, 2000 miles since last oil change. NO codes, only radio showing code?

ECU SWAP from 850R to 850 T-5

Re: ECU SWAP from 850R to 850 T-5