timing problem after TH400 install
03-19-2005, 10:17 PM
#1
9 Second Club
Thread Starter
iTrader: (2)
Join Date: Jul 2002
Location: on the dyno tuning in MD
Posts: 2,583
Likes: 0
Received 1 Like
on
1 Post
timing problem after TH400 install I am having a weird timing problem after swapping my A4 to TH400. I used to have 28.5 degrees at WOT and it showed such on logs. Went to TH400, but didn't use a speed sensor as the car is pretty much a race car and I didn't need the speedo. Others say they have done it and it worked.
Now at WOT, I start off at 28.5, but when I shift into 2nd, it drops in steps to around 16, and when I shift into 3rd, it drops to 10.5 and stays there through the traps.
The only place I can find numbers like that are in the base spark tables. My TPS is showing 100%, so I don't see how it could be forcing me there even if it sees vss as zero. I do have a neutral safety switch, and it is hooked into the factory harness, so it knows when I am in park or not.
Today, I hooked up the speed sensor to the old ABS sensor on the rear wheel. By playing with the gear/tire ratio, I actually got it to read pretty close to actual speed, although it seems a little erratic at times. I can't tell for sure if it helps the timing on a full WOT run cause it started to rain. It does seem like it held timing slightly better for the short blast I tried.
Any idea how I am seeing such low timing at WOT with no KR?? Any input would be appreciated. I'll probably end up getting the proper vss conversion parts to do it right - just hope that it is not something else and the $200 will be for not.
Now at WOT, I start off at 28.5, but when I shift into 2nd, it drops in steps to around 16, and when I shift into 3rd, it drops to 10.5 and stays there through the traps.
The only place I can find numbers like that are in the base spark tables. My TPS is showing 100%, so I don't see how it could be forcing me there even if it sees vss as zero. I do have a neutral safety switch, and it is hooked into the factory harness, so it knows when I am in park or not.
Today, I hooked up the speed sensor to the old ABS sensor on the rear wheel. By playing with the gear/tire ratio, I actually got it to read pretty close to actual speed, although it seems a little erratic at times. I can't tell for sure if it helps the timing on a full WOT run cause it started to rain. It does seem like it held timing slightly better for the short blast I tried.
Any idea how I am seeing such low timing at WOT with no KR?? Any input would be appreciated. I'll probably end up getting the proper vss conversion parts to do it right - just hope that it is not something else and the $200 will be for not.
