I know this is beating a dead horse, but I have a code 51 problem. I did a swap from N/A auto to Turbo/5spd last year, using the 5spd engine harness and ECU. I have had a code 51 consistently since. I have checked and double checked my TPS, and it is adjusted perfectly and well within spec. My CEL stays off until I start rolling and exceed about 1,500 RPM and I believe the heart of my issue is that it is not seeing the neutral signal. What can I do to fool my Auto chassis harness into believing that everything still is how it is supposed to be. I am pulling my hair out on this, and have searched endlessly to no avail thus far.
Code 51 after 5spd swap, how to solve the problem?
- Thread starter SupraMan1987
- Start date
What do you mean the CEL stays off until exceeding 1500 rpm? When it comes on does it blink or stay on? Are you operating the car in diag mode?
My CEL stays off until I exceed about 15-1800 RPM. When I exceed that RPM my CEL stays on until I cut the car off and restart it. It then stays off again until I exceed that RPM threshold again. I don't believe it is in diag mode, no.
Then you have another code(s). 51 is real time. It doesn't get set in memory and will not illuminate the MIL unless the ECU is in diag mode. Therefore if the MIL is coming on and you're not in diag mode the illumination is unrelated to 51 and is being set by something else.
Now if you have 51 in diag mode with the AC off and throttle closed that's a different story and could be neutral switch related. On the other hand if, when in diag mode, 51 doesn't come on until the throttle is cracked (that'd be about 1500 rpm with the engine running) everything is normal.
Now if you have 51 in diag mode with the AC off and throttle closed that's a different story and could be neutral switch related. On the other hand if, when in diag mode, 51 doesn't come on until the throttle is cracked (that'd be about 1500 rpm with the engine running) everything is normal.
I'll have to double check, but I don't think I left the car in diag. It won't rev past a certain RPM in diag mode will it? I know I used a snapon tool to force it into diag before, and not the paper clip method, any possibility that it is stuck in diag now?
It'll rev all day long in diag. You could drive it around like that forever and not notice except for the MIL doing something all the time. You need to check for other codes along the 51 behavior I mentioned.