Clutch Position Switch input needed for tune?
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Clutch Position Switch input needed for tune? Hey Guys
I have a T56 swap with an 2002 A4 ECU that I'm learning to tune.
One issue I've been having is an intermittent lean condition as I come off steady throttle (coasting to a stop) and then slowly accelerate (behind someone at a light). I'm sure there is some transitional fueling work needed but my question is should I add a clutch position switch before messing with the tune? Could the switch input to the ECU help fix this?
I have a T56 swap with an 2002 A4 ECU that I'm learning to tune.
One issue I've been having is an intermittent lean condition as I come off steady throttle (coasting to a stop) and then slowly accelerate (behind someone at a light). I'm sure there is some transitional fueling work needed but my question is should I add a clutch position switch before messing with the tune? Could the switch input to the ECU help fix this?
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From: Indianapolis
I searched both here and on HPT's site and didn't find much of any info on the clutch switch having input on the spark or fuel. I guess I will figure out how to mount one and wire it in and see if there are any changes.
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I wouldn't think the clutch switch would do anything except keep you from starting the car without the clutch depressed.
I would assume the spark/fueling is paying attention to TPS, MAP, O2's while in closed loop.
Lean condition is possibly caused by bad 02's (giving faulty readings) or vacuum leak. While coasting off throttle you have higher vacuum being pulled due to engine braking if I'm not mistaken. Which is perfect time to see vacuum leaks.
I would assume the spark/fueling is paying attention to TPS, MAP, O2's while in closed loop.
Lean condition is possibly caused by bad 02's (giving faulty readings) or vacuum leak. While coasting off throttle you have higher vacuum being pulled due to engine braking if I'm not mistaken. Which is perfect time to see vacuum leaks.
Naptown, I was having weird issues coming to a stop, or throttle off coasting on my LQ9/T56(228R and Longtubes). I wired in the CPP(Clutch Position Sensor) to the Blue Connector on my ECM into Pin 35: https://ls1tech.com/forums/conversio...version-3.html (post 56) . This allowed me to use the Throttle Follower and Cracker tables correctly-no more stalling issues.
Later I realized I could do cooler things, like pull timing out of the certain areas of the base timing table in P/N{B5933}..this got my revs to drop quickly after I would clutch and rev up. Before I did that it , I would rev up at someone and the revs would drop embarrassingly slow.
The CPP wiring is stupid simple-one side goes to pin 35, the other to ground.
BTW, that Nissan looks freaking awesome.
Later I realized I could do cooler things, like pull timing out of the certain areas of the base timing table in P/N{B5933}..this got my revs to drop quickly after I would clutch and rev up. Before I did that it , I would rev up at someone and the revs would drop embarrassingly slow.
The CPP wiring is stupid simple-one side goes to pin 35, the other to ground.
BTW, that Nissan looks freaking awesome.
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It's possible the issue is mechanical but not likely, I replaced all the intake gaskets when I did my cam swap. Hell I even followed the torque procedure for the intake for once! 
I know the VSS has some input on the fuel and spark tables so I was thinking the clutch position may also. I guess worse case I get the reverse lockout working so I don't have to use the switch I put in.
I know the VSS has some input on the fuel and spark tables so I was thinking the clutch position may also. I guess worse case I get the reverse lockout working so I don't have to use the switch I put in.
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Jet,I didn't see your post on my phone before my last. Awesome info!
I figured the ECU liked to see the clutch position. I'm going to throw one in this weekend and if I can get through the snow in my driveway do some logging drives.
Your Olds rocks, looks like we are cut from the same cloth lol
I bought the 280 from a guy in the North Chicago burbs
I figured the ECU liked to see the clutch position. I'm going to throw one in this weekend and if I can get through the snow in my driveway do some logging drives.
Your Olds rocks, looks like we are cut from the same cloth lol
I bought the 280 from a guy in the North Chicago burbs
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From: Indianapolis
Suitable switch purchased
Bracket fabricated
Wired into the ECM
I'm going to clean up some of the janky swap wiring that I did when I didn't expect it to start on the first try and wait for some decent weather to try it out.
My ltfts look pretty good except in the cells that are affected down low easing away from a light so hopefully this will help out.
Bracket fabricated
Wired into the ECM
I'm going to clean up some of the janky swap wiring that I did when I didn't expect it to start on the first try and wait for some decent weather to try it out.
My ltfts look pretty good except in the cells that are affected down low easing away from a light so hopefully this will help out.
