Gen4 ITB tuning = reduced engine power

[ccrp]

I finally got things together except one last issue which causes major grief. I have a brand new Harrop ITB, the drive by wire version, on that track LS7 which causes reduced engine power (P1516) anytime I hit more then 60% TPS.

all tables are maxxed out, I nudge P2101 TPS error values like Bill suggested but it comes up as soon as I hit WOT and let go off throttle. It doesn't seem to come on as long as I step into it, it comes on right when i get out of WOT.

that would be real show stopper for that system and not sure if this is a 06 PCM issue or if there is a workaround it.

anyway, file enclosed

[ccrp]

just found out, engine does not have to run to go into reduced power. Engine off, ignition on and after 5 times WOT reduced engine power. WTF?

[Guero68]

i am kinda of fighting the same thing...i turned on the ignition after about 10-15seconds reduced power is enabled.....i did a write entire i think that fixed my issue havent gotten the reduced power but its only been one day..

[Bill@HPTuners]

I have a feeling it might be a mismatch with what the TAC module is commanding(which can also throw you into reduced power mode via P1516)

[ccrp]

Bill, I believe the same. I confirmed with Harrop that the actuator is off an brass blade TB and it runs well with their 2009+ cars.

now this is a 2006 E38 which had a silver blade TB and now i am exploring options to make system work and you might be right that it causes TAC to freak out.

so either find a way to use silver blade actuator or run a 2009 PCM in a 2006 car, piggy back or not.

[c.u]

This is just a test. Set your tps sensor 2101 back to stock setting. Then po101,po106,po121 max to-40. Set po68 enable rpm to 8192. Then set the po1516 to 3 no error.

[ccrp]

i tried those settings. It no longer goes into REP with engine off, but still goes into REP now anytime over 70% TPS.

I adjusted all end stops, linkage, etc....but basically no real change

what I am trying to save race on weekend ist to keep stock TB but run just two wires to new actuator motor and ditch new TPS sensor inside.

[DSteck]

Try the electronic throttle mapping from a 2009 Corvette.

[ccrp]

did that too, no change. Like Bill said, it would be tha TAC CPU itself but HPtuner has no access to it.

[DSteck]

Hmm. I wonder if you might need the pedal assembly from a 2009.

The older style actuator is likely the best bet though.

[Shrek]

Couple of things to consider ...

The tune you posted is odd - the calibrations for segments 2 through 6 are the most up to date via TIS, for that VIN (Corvette). Segment 1 (the OS) is odd. It is missing a digit, and is not even close to the OS that one would expect to find - given the rest of the calibration.

Operating systems for Gen IV Corvette TB fall into two main groups. The 2005-2008 "Silver blade" TB, and the 2009+ "Brass blade" TB.

The E38 ECM is essentially a dual core processor - with one of the cores solely dedicated to monitoring the ETC (electronic throttle control). This area of the ECM is "Write only" - and can't be read, and therefore can't be modified.

Given that the system you purchased is designed to work with the "Brass blade" TB - using an E38 with a 2009+ Corvette calibration seems like a probable starting point.

Just some thoughts ... have never used a Harrop system ... they look cool, but seem fraught with tuning issues (at least initially).

[DSteck]

The HP Tuners custom operating systems look as though they're missing a digit. That's why the segment stands out.

[ccrp]

i got it working temporarily, but it is a redneck setup which at least should get me over the dyno days and the race.

I plugged in the stock silver blade TB, took the blade out and fixed with tie wraps to the AC lines. I spliced into the Actuator wires and connected them to the Harrop module, so basically PCM sees old actuator and TPS sensors, the Harrop runs just parallel with its TPS sensors nor connected. Just came back from a longer testdrive and it never went into REP that way.

now in the long run I need a solution, installing a 2009 throttle pedal and PCM would be no issues, but could it be installed into a 2006 car? won't there be no Class2 serial issues or so casuing active handling, ABS etc. to go berserk?

all the other issues like fuel sensor wiring etc. I can take care off

it looks like the best solution to upgrade in winter. Both are E38's

[c.u]

Have you played with the ect area scalar from the 09 to the 06?

[Shrek]

The HP Tuners custom operating systems look as though they're missing a digit. That's why the segment stands out.

Thank you sir ... missed that it was a COS when I took a quick look.