Car won't start, TPS won't switch maps

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Sep 4, 2015 | 07:04 PM
  #1  
I've been working on tuning my IX lately (on 93). Took it out last night for a run, logged it max of 2 knock counts so nothing terribly out of the ordinary. Drove home just fine.

Went to pull it out of the garage today and it won't start. Cranks but won't start up. I had a new tune on my laptop that I was hoping to run tonight so I just reflashed, no issues there ecuflash worked just fine.

I turn the key to ignition, hold the go pedal down to change maps (I make my changes to the alt map currently) and nothing. Won't change maps by ththe TPS which was previously working just fine.

Any suggestions where to start? Could this be one of the engine fuses that would have these symptoms? The TPS? I'll add in here that all I changed from my previous tune was mid to high rpm AFR's and timing.

TLDR: car won't start, TPS won't switch maps, ecuflash will read/write just fine.

Thanks!
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Dec 18, 2015 | 12:43 AM
  #2  
I'm in the same boat....did you ever fix the problem?
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Dec 18, 2015 | 05:29 AM
  #3  
Try to flash to a previous working rom perhaps.
Had that issue on my 9 and it turned out something i changed in upward wastegate duty corr table.
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Dec 18, 2015 | 10:18 AM
  #4  
Sorry, I forgot to ever post in here that i cleared it up!

Same as Dubai mentioned, I had made a change to my WGDC clrrection tables. In my case the change would let my car start and run literally perfectly a couple of times and then no more. It would just crank. Because I was tuning, I made that change and something like revision 10 of my tune, drove it exactly twice to log it and then proceeded to flash to revision 11. When that wouldn't starut, I thought "no problem, rev 10 was working. Just flash back to that". Sure enough back to that one where my WGDC changes had first been made and still no start. Back to rev 9 with my original WGDC corrections and no issues since!

The symptoms pretty closely mimic the crank sensor as I understand it. There's a plug for it on the back of the engine near the intake can gear attached to the valve cover. Should be a little 3-wire clip that pulls right up. You can back pin that to check the function of your crank sensor without tearing anything apart. Pull your plugs out and manually crank the engine over with a breaker on the crank pulley and watch the voltages across the crank sensor wires. When I saw that mine was still reading fine I figured out to go back another tune and solved it.

I'm no expert but feel free to PM or post here if you want some help troubleshooting or to know exactly what ECU changes I had made!
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