u0107 and reduced engine power

[Flyer]

I have a customer who just did a cam swap and mild head work. Tuned the truck, running great. The guy goes to the track, pulls the headlight out and can never make a full pass. After doing some logs and looking into the problem a little deeper, it looks like it's a problem with the ETC and the PCM. I know there's a table that EDIT can see that dictates what a 'safe' limit of air is for the ETC. When the 'safe' limit is exceeded the PCM thinks something is wrong with the throttle actuator and shuts ever thing off, thus 'Reduced Engine Power' mode.

I've bumped the P0101 and P1514 up enough where they are unmistakably not the problem. Those however are evedently not the tables I'm looking for to adjust.

I know there are others with this problem, and I'm sure there are others that have had the problem and fixed it with HPTuners. Any help will be GREATLY appreciated by me and the customer. Thanks in advance!

FWIW, the limit seems to be .72 gms/cyl above 5k.

[Russ K]

Are you getting both codes P0101 and P1514? The stock P1514 table is .67 g/cyl @5000 rpm @100% tps. I muliply that whole table by 2. The max is 4
g/cyl. Is the maf being used? If the maf is functioning and the ve table is way
out, then P0101 will set.

Russ Kemp

[Flyer]

This is not a SD tune, so the MAF is being used. No other codes other than the u0107 is being thrown.

The VE table is in in the lower ranges. It has been smoothed to the upper part of the tables (100-105kpa) but they prolly aren't dead on like the rest of th VE table.

[Russ K]

Ok so your just getting code PO107 map sensor circuit low voltage. That could be caused be either the map sensor reference voltage from the pcm being under
~ 4-5 volts, or the map sensor is at fault. On a 1999 5.3 Truck that had this code, it had only ~ .9 volts to the map sensor with the key on engine off. The pcm was the problem.

Russ Kemp

[Flyer]

u0107 ... Something about lost comm w/ throttle body actuator.

[Russ K]

I'll check that code U0107 on my Aldata at work and get gack to you then. I'm thinking there's a problem with the tac module. Is the harness plugged into the etc motor ok?

Russ Kemp

[Flyer]

This happens as soon as it hits .72 in the UPPER roms. It hits that in the lower and it's OK, but it hits it in the upper and the problem arises.

[EC_Tune]

Could you post your tune & a scan where the truck quits on you?

EC

[Flyer]

I'm gonna bump this up. The truck cuts out at around 5300-5400 rpm and .72 gms/cyl. The scans show that much gms/cyl earlier in the rpm range, but doesn't cut out until after 5000 rpm.

[Flyer]

Here are some logs.

The one where it cuts out, I lost comm with the PCM once it tried to reset everything so you can't tell what's going on really.

[Flyer]

Anyone ....

[Chris@HPTuners]

post your file and we might be able to see something you left out.

U0107 doesn't sound good, are you sure there's not a wiring issue?

Chris..

[Flyer]

As far as the customer says ... no. I think it happens to predictably to be a wiring isue though.

File coming once I get my laptop up and running.

[Flyer]

I think it's a table unseen with HPT to be honest, although I hope I'm wrong.

I had a similar problem before when I was still using EDIT, but edited a couple of tables and got it fixed.

[Chris@HPTuners]

are you seeing P0068 at all? I've only ever seen u0107 when you start messing with the ETC and Pedal position calibrations too much (and this can permanently affect your PCM in some cases). U0107 errors are usually caused by ETC positioning errors but we don't allow editing of any of the tables that generally cause this, so i'm a little stumped as to what is causing this.

On ls2's i've seen this kind of thing when the spring tension on the ETC connector pins weakens giving an intemittent connection, but never seen it on an LS1 before.

Chris...

[Flyer]

u0107 is the ONLY code it throws. It will throw the code once before going into REP mode. When it does this, again, its' on a WOT run in the upper RPMs. When it does this, it gives a strong backfire, my laptop looses connection, and then the engine resumes, running strong. It takes a while for me to regain connection. I can ONLY assume this is the PCM resetting itself and other modules.

On the next run throwing the code it will give just go into REP mode. It doesn't pop, loose connection, or anything.

[Flyer]

Chris, I would like for you to look at these 2 edit files. It's a table labaled MAX AIR ETC that I think is missing. Can you please give me your thoughts on this?

These files are off a 2002 and are very close to what/where I am having a problem with the 2004.

[RedWS6 00]

This may be a crazy suggestion, but I have heard of it before and its free to check/fix

Is the battery on tight? I have seen a post from someone who has something simular, under heavy accelleration the battery moved, sutting down the PCM. Think the battery holder shorted out the termials.

It could be something mechanical moving which pinches some cables.

[Flyer]

I'm gonna give this another bump.

[Chris@HPTuners]

Chris, I would like for you to look at these 2 edit files. It's a table labaled MAX AIR ETC that I think is missing. Can you please give me your thoughts on this?

These files are off a 2002 and are very close to what/where I am having a problem with the 2004.

I cannot view those files, can you email me a screenshot of the table? Many of these tables are related to P1514/0068 which you are not seeing so is not the cause. I believe your problem is that the TAC/ETC controller is shutting down due to its own diagnotistics failing which cannot be modified.

Our competitors often see this problem when you go messing with various ETC related tables that control the operation of the ETC. The TAC runs its own tests to verify operation of the ETC. In some cases this can permanently disable your PCM, hence why we won't ever add those tables.

I don;t think the PCM holds the answer to your problem, although if you send me the screenshots of the tables i will definitely check them.

Chris...