2006 CTS V FAST Manifold and NW 102 TB Reduced Engine Power

[Robert C Morgillo]

I am having trouble with this one. I am tuning a LS6 in a 2004 CTS V. It has a 221/228 @ .050 cam on a 112 Center line. PRC heads and a FAST intake with a NW 102 throttle body. 50 pound DeatschWerks injectors and full length headers with open exhaust It has a cold air intake and 165 deg thermostat. Initially the vehicle was tuned by me with just the cam, thermostat, exhaust and heads changed. It ran very well. The intake and Throttle Body were installed and I put an initial MAF tune on it and an SD tune. Several times it went into REP mode during SD tuning but not during MAF tuning. I did get a P0068 code during SD tuning. I set it to Disable with No Error Reported. It was way lean on the top also, so I thought that was it. I added some fuel and put an initial SD tune in with no further trouble. Performance was good.

I loaded the new tune in with the MAF/SD enabled. Performance was excellent on the first couple of shifts then it went into REP under full throttle. I am unable to get to full throttle without hitting REP. I would truly appreciate any help! I have read as much as I can find and I have exhausted my thoughts. I have read the trouble a lot of people had in the past but it seemed to always be a tuning mistake. I have read quite a few who had trouble with the NW throttle body. It was usually a tuning error. If it is I can't find it!



Gibbs 2004 CTS V tuning Final.hpt

[LSxpwrdZ]

I made some tweaks to some parameters in the background to see if it solves your issue. Try this and report back if it did. I will try to get HPT to add these parameters if it works.

Gibbs 2004 CTS V Tuning Final Hex Edited.hpt

[Robert C Morgillo]

Thanks a ton for looking it over LSxpwrdz! I am hoping to get back on it in the next few days. I noticed the changes you made on the parameters I have control of. I was afraid to set the values on the Diagnostics to 4.1. I always thought you shouldn't max them out. I have also seen a lot of you Pro's max them out! I take it it doesn't matter if you max them. I did not know about the ETC Engine RPM Limit Master Enable.

I will report back as soon as we take it out and bring it back. Thanks for your time and for the tips! I take it there might be something you had to fix in tables I cant see.
Bob

[LSxpwrdZ]

Some settings you don't want maximum values in but those tables aren't one of them. The settings I adjusted in the background are boundary values for throttle error. By setting those boundaries wider and the failure count higher it shouldn't fail as easily as it did with stock OEM parameters.

Throttle 1.png

[Frost]

Some settings you don't want maximum values in but those tables aren't one of them. The settings I adjusted in the background are boundary values for throttle error. By setting those boundaries wider and the failure count higher it shouldn't fail as easily as it did with stock OEM parameters.

Throttle 1.png

That's a nice set you have added there James!

[LSxpwrdZ]

That's a nice set you have added there James!

Luckily these parameters have worked in certain scenario's for REP and 1516 code but it's still hit or miss. Hoping this solves his issue to add to a bit more testing I've done thus far. Would like to release these parameters along with all the transient throttle tables that are missing in a lot of the Gen3 OS's especially P59 OS's.

There is so many unseen parameters in the Gen3 stuff that I can't imagine how much is actually missing from the Gen4 and Gen5 stuff.

[Robert C Morgillo]

I am expecting to get the changes by James loaded in the next couple days. I will definitely stay on it. The vehicle is coming back to the garage shortly. I will say if not for the REP "bug", the FAST intake, DW injectors and the NW throttle body runs and behaves very well. If we can get past the REP you really couldn't ask for much more from bolt on's.

[Robert C Morgillo]

LSxpwrdZ James, I put the tune in last night and sent it out for a run. It is improved but still going into REP. It was able to make a few good pulls at WOT but goes into REP at 5800 to 6000 at WOT. Is it possible to adjust it a little more? I think we might be getting there.

Is there a way to disable the REP completely?

[Robert C Morgillo]

I also noticed I did not have these settings modified.

Engine-Airflow-Electronic Throttle-[ECM] 33012 - Throttle Max Rotation % vs. Pedal Should I set all to 100% (There is a warning on this one)

Engine-Torque Management-General-[ECM]-12850 - ETC TPS Max vs. RPM vs. % Max Available Torque Should I set it 100%?
Engine-Torque Management-General-[ECM] 12851 - ETC Torque Mgt Cylinder Disable vs. Mode Should I set it to 255?
Engine-Torque Management-General -[ECM] 12840 - Retard vs. % Torque Reduction Should I set it to 0?
Engine-Torque Management-General -[ECM] 2820 - Maximum Net Engine Torque Should I set it to 639?

Are these settings OK? I noticed the warning on Max Rotation vs. Pedal. This is primarily a track car. I truly appreciate your help on this. I am pulling what little hair I have left out on this one!

[Frost]

Engine-Airflow-Electronic Throttle-[ECM] 33012 - Throttle Max Rotation % vs. Pedal Should I set all to 100% (There is a warning on this one)

Does your throttle body have a gold blade? If yes, set this table to 97% instead of 100%... so yes, limiting the blade to 97%. Flash and re-test. If you only get REP under full throttle, it will likely stop. Let's look at kPa there too... it should still look like full WOT.

[Robert C Morgillo]

Frost, it is a Nick Williams 102. I am pretty sure it was silver. Are you thinking of the LSIII Throttle Body? It would be great to get this thing to run in WOT. It runs so well every where else. What do you think about those other settings?

[Frost]

Just give that a quick test when you can. If it works, you can then remove the TB, run the sweep and verify that it's still opening all of the way. None of the rest of the items mentioned are focus for this error.

[Robert C Morgillo]

OK I have a positive update. I made the changes below. It runs great good power, trims are right on. It will only give me 96.5% throttle however. I am not to sure that is a problem! It is strong. The changes James made to the Hex gave us about 400 more rpm before it went into REP. With the following changes it no longer goes into REP. I think it was the [ECM]-33012 Frost recommended that stopped it from going into REP. I am wondering if there is something about the NW Throttle Body and full throttle opening vs the settings James was working on? Maybe a little more desensitizing in the Hex? Thanks so much for the help!

Engine-Airflow-Electronic Throttle-[ECM] 33012 - Throttle Max Rotation % vs. Pedal I set all to 97%

Engine-Torque Management-General-[ECM]-12850 - ETC TPS Max vs. RPM vs. % Max Available Torque I set it 100%
Engine-Torque Management-General-[ECM] 12851 - ETC Torque Mgt Cylinder Disable vs. Mode Should I set all to 255
Engine-Torque Management-General -[ECM] 12840 - Retard vs. % Torque Reduction Should I set all to 1
Engine-Torque Management-General -[ECM] 2820 - Maximum Net Engine Torque I set it to 639

[Robert C Morgillo]

Update: It is acting differently now that is for sure. It was running good. Suddenly at full throttle second gear, it went into REP at 4000 rpm. It seems to be getting random. Full throttle may or may not trigger it at any time.

[LSxpwrdZ]

The parameters I changed are mostly maxed out meaning there wasn't anymore adjustment however there are a few other parameters I maxed out to see if it would cure your REP. Also limited the throttle to 90% both in the background and the available tables. A 102-103mm TB will not notice any measurable difference with 10% throttle. Seems to me the throttle may be over extending anyhow which is pushing the TPS voltages out of range causing the REP.

Gibbs 2004 CTS V Tuning Final Hex Edited Rev2.hpt

[Robert C Morgillo]

Thanks James! I appreciate your not giving up on me. I will get the vehicle in here ASAP and load it in.

Your comment about over extending is interesting. I was reading from a race car builder in Australia. He was having this problem and was speaking with another about it. They stated they "Fixed" it by putting a block under the accelerator pedal. I guess I don't know what to think about that!

[Frost]

Yeah I've seen it with aftermarket TB's (even when blade "color" is consistent with app like here) and is whay I tried to limit your blade. I start at 97% (which seems to let me use LS3 TB's on C5's) and work down.... James's limiting ought to make it stop.

[LSxpwrdZ]

Curious if any of the latest adjustments fixed your issue or not?

[Speedmaster747]

Curious if any of the latest adjustments fixed your issue or not?

I'm curious too. i just got one at the shop doing the same, with a large cam, fast, injectors and a silver blade NW102

[TINKRD]

Bump. Chasing similar issue.