2013 FRS timing issue

[NoHaveMSG]

Originally Posted by jonho

Its odd that it ran fan the whole time we had it on the old ECU and tabbed gears then when we rebuild it runs but shows 18* advanced on intake cams. My theory is someone redid timing before we owned it did a replacement ECU tabbed gears and had the intake cams off a tooth then on startup thats how it learned it??

I'm surprised it ran like that at all without throwing a code.

[Ultramaroon]

Originally Posted by Ultramaroon

those are views of first-gen and second-gen sensor outputs. The polarity reversal is solely a function of switching from valleys to hills. I wonder if the ecu can learn to compensate for the change in one direction. ...one way trip for the initial position values. I think that's what they're called.

I don't know if I'm writing in Sanskrit but this is almost certainly what happened. Old ECU can read output of tabs and adjusts IPV table accordingly. I'll guess that it ran like shit but would have to work out the numbers to verify.

Once the ECU adjusts to tabs, switching back throws the measured discrepancy out too far for the servo system to pass the initialization test. That's when the zero value is reported, the system gives up, and it throws the p001(6-9) codes.

[jonho]

it was running pretty good I think. On a Mustang Dyno was 260hp and 217tq with 91 octane at 5lbs of boost. We will see how it does with a good build and lower compression in a week or 2 after some break in miles.

[DarkPira7e]

Originally Posted by jonho

it was running pretty good I think. On a Mustang Dyno was 260hp and 217tq with 91 octane at 5lbs of boost. We will see how it does with a good build and lower compression in a week or 2 after some break in miles.

You are going to lose a good amount of power if you lower compression, please keep that in mind.

[NoHaveMSG]

Originally Posted by Ultramaroon

I don't know if I'm writing in Sanskrit but this is almost certainly what happened. Old ECU can read output of tabs and adjusts IPV table accordingly. I'll guess that it ran like shit but would have to work out the numbers to verify.

Once the ECU adjusts to tabs, switching back throws the measured discrepancy out too far for the servo system to pass the initialization test. That's when the zero value is reported, the system gives up, and it throws the p001(6-9) codes.

I think you are right, I am just still surprised it can learn it. I thought the difference in cam positions sensors and gears was one of the issues swapping a facelift engine into pre-facelift along with the different crank position sensor and reluctor wheel.

[jonho]

Originally Posted by DarkPira7e

You are going to lose a good amount of power if you lower compression, please keep that in mind.

Yes if we kept it the same but doing other upgrades and a 3port pretty similar build to yours actually and will be on flex fuel.

[Ultramaroon]

Originally Posted by jonho

it was running pretty good I think. On a Mustang Dyno was 260hp and 217tq with 91 octane at 5lbs of boost. We will see how it does with a good build and lower compression in a week or 2 after some break in miles.

If that valve timing isn't stock, be careful. May have been tuned for peak performance with offset angles, and not noticing the deviation from typical values. Not sure. Just things that I'd sweat.


edit:wait, nvm. new ecu duh

[Ultramaroon]

Originally Posted by NoHaveMSG

I think you are right, I am just still surprised it can learn it. I thought the difference in cam positions sensors and gears was one of the issues swapping a facelift engine into pre-facelift along with the different crank position sensor and reluctor wheel.

I'm equally surprised. I knew the cam sensors were the same but still... wow.

[jonho]

Originally Posted by Ultramaroon

I'm equally surprised. I knew the cam sensors were the same but still... wow.

so really it would just learn if the change was 5v or 0v a dip or a peak. I would see how it could learn that everything else being the same.

[Ultramaroon]

Originally Posted by jonho

so really it would just learn if the change was 5v or 0v a dip or a peak. I would see how it could learn that everything else being the same.

The old ECU triggers on the negative-going part of the waveform. The signal from the tabbed reluctor has a negative-going part but it's at the end of the pulse, not the beginning.

[jonho]

Well so far so good have 600 miles on it issue free! Thanks for the help understanding what was going on with it!