Reduced engine power after autoTune

[mtnman]

I was going through the Updated AutoTune Tutorial (10-02-05), loading the Map table changes to B0101 and every time I took a test drive and got above 3000 RPMs for any length of time the "reduced engine power" message came up and the engine bogged down.

After setting the P0101, P0102, and P0103 back to MIL (instead of NO MIL) and enabling the cat converter B0701, the problem seems to be gone. Anybody else had this problem?

[Dirk Diggler]

if you are throwing P1514 gor into table C6010 and rasie all the values by 20% or so

[mtnman]

Yes, it was throwing P1514 codes. {C6010} doesnt exist within my tune.

[mtnman]

Looks like "dfe1" may have answered my question:

" Also note that if you convert to MAFless, you'll have to do some considerable rework to the predicted airflow table. If you don't and actual air flow exceeds predicted, the system will go into reduced power mode. No big deal, and easy to clear, but the throttle will have no effect until you clear the codes."

More work on the airflow table?

[Dirk Diggler]

Yes, it was throwing P1514 codes. {C6010} doesnt exist within my tune.

Sorry i meant C6101 that is the predicted airflow table

[GMPX]

Didn't someone create a scantool map for this?.

Cheers,
Ross

[dfe1]

One way to eliminate the problem is to set the values in the predicted max airflow table (C6101) to maximum. Not a good idea because that removes a safety valve. Instead, log Air Flow Grams/Cyl and when you set the code, you'll know what table cells to change. Do that a few times and it will be pretty easy to develop the values you need to redo the whole table. I'd be happy to send you the table I developed, but since it's for a C5, it will only be a starting point-- truck engines run under a condsiderably heavier load than passenger cars because they're 2,000- 3,000 pounds heavier.

[Black02SS]

Didn't someone create a scantool map for this?.

Cheers,
Ross

Sorta. He created a MAP and was using that ONLY to adjust for his AFR. Did not touch the VE Table at all.

[caver]

If you adjust the VE table without doing anything to the maf table or vice versa you can get errors because the ecu is always comparing the 2.

The maf map was to use after you set the VE table up I use it all the time and it works perfectly.

[mtnman]

I was trying to do the AutoTuneVE tutorial and got this and other errors. I was hoping that following the tutorial would be pretty much a "cut-and-dry" process. The day after I thought that I had the LTFTs tweaked, the engine light came on. I didnt have time to check the codes, so I just resorted to the pre-autotuneVE tutorial *.tun. I'm not dogging the tutorial or the product, since its probably mostly user error, but it just seems like there are more problems than there should be when following a documented tutorial such as this. I've gone through this tutorial over and over about 5 times and things just dont sink up. I've noticed one obvious error where it mentions saving the tune file as one name then it states to flash another *.tun file to the pcm on the following line.

[caver]

Started mapping a s/c Monaro today running 2 bar.
Kept getting the reduced power fault untill I raised the ETC predicted airflow values by 120%.

[mtnman]

One way to eliminate the problem is to set the values in the predicted max airflow table (C6101) to maximum. Not a good idea because that removes a safety valve. Instead, log Air Flow Grams/Cyl and when you set the code, you'll know what table cells to change. Do that a few times and it will be pretty easy to develop the values you need to redo the whole table. I'd be happy to send you the table I developed, but since it's for a C5, it will only be a starting point-- truck engines run under a condsiderably heavier load than passenger cars because they're 2,000- 3,000 pounds heavier.

So, are you saying that the auto VE tutorial isnt complete? There are other unmentioned tables to map?

I followed the instructions exactly as stated in the tutorial. Is there a better tutorial out there to tweak the LTFTs?

[Black02SS]

The autotune is just a guide as every vehicle is different. The autotune was designed to show you how to use the BEN to tune the ve table, that is it.

[joecar]

dfe1 is saying to temporarily set C6101 to max while tuning, and to log DYNAIR so you can create a new C6101 table from DYNAIR plus some percentage;
C6101 gives you a factor of safety in case something goes wrong (MAP/IAT fail causing VE lookup/calc to go wrong...).

[TAQuickness]

One way to eliminate the problem is to set the values in the predicted max airflow table (C6101) to maximum. Not a good idea because that removes a safety valve. Instead, log Air Flow Grams/Cyl and when you set the code, you'll know what table cells to change. Do that a few times and it will be pretty easy to develop the values you need to redo the whole table. I'd be happy to send you the table I developed, but since it's for a C5, it will only be a starting point-- truck engines run under a condsiderably heavier load than passenger cars because they're 2,000- 3,000 pounds heavier.

So, are you saying that the auto VE tutorial isnt complete? There are other unmentioned tables to map?

I followed the instructions exactly as stated in the tutorial. Is there a better tutorial out there to tweak the LTFTs?

Per the AutoVE doc

This write up has been written for informational purposes only. In other words, use at your own risk.

If you would like a better tutorial, now may be the time for you to write it ;)

[joecar]

If you would like a better tutorial, now may be the time for you to write it ;)
Yes, that's right, anyone who can add knowledge should. 8)

[joecar]

resonance coupled plasma discharges
Mate, he he, cool, I need to get me some of those, or can I just tune them in... :D :D :D

[TAQuickness]

resonance coupled plasma discharges
Mate, he he, cool, I need to get me some of those, or can I just tune them in... :D :D :D

Here's a so-so write up on them.

http://www.ls1tech.com/forums/showthread.php?t=398757&highlight=top

It's an excellent compliment to the blinker fluid. :D

[mtnman]

One way to eliminate the problem is to set the values in the predicted max airflow table (C6101) to maximum. Not a good idea because that removes a safety valve. Instead, log Air Flow Grams/Cyl and when you set the code, you'll know what table cells to change. Do that a few times and it will be pretty easy to develop the values you need to redo the whole table. I'd be happy to send you the table I developed, but since it's for a C5, it will only be a starting point-- truck engines run under a condsiderably heavier load than passenger cars because they're 2,000- 3,000 pounds heavier.

So, are you saying that the auto VE tutorial isnt complete? There are other unmentioned tables to map?

I followed the instructions exactly as stated in the tutorial. Is there a better tutorial out there to tweak the LTFTs?

Per the AutoVE doc

This write up has been written for informational purposes only. In other words, use at your own risk.

If you would like a better tutorial, now may be the time for you to write it ;)


Yes, I partially agree. Someone with better experience (than myself)tuning trucks should write a better tutorial than this one since it appears to be very incomplete.

This document is very incomplete if someone follows it and then gets a "reduced engine power light" until a previously "untainted" program is flashed back into the pcm.

Maybe more should be added to the disclaimer of this document such as "If you follow only this tutorial, your vehicle may raise a "Reduced Engine Power" code and your vehicle may become virtually unusable until a re-flash of the original tune is made into the PCM"

[Extinct]

Mine did not set any codes, however the car did fall on its face if I got into it too much when MAFless ? Do you guys think this is the same situation ? Why would it not set any codes for me ? Any suggestions ?

[caver]

Maybe more should be added to the disclaimer of this document such as "If you follow only this tutorial, your vehicle may raise a "Reduced Engine Power" code and your vehicle may become virtually unusable until a re-flash of the original tune is made into the PCM"

Seems to me that you need to understand that using EFI-Live will require you to engage your mind.
If you are unwilling to do so than you should rather pay someone to tune your car for you.

If the Predicted airflow is exceeded then a "reduced powermode" display comes up on the dash.If you switch the car off for 15 seconds then it resets and u can drive normally again. It will also set a DTC.

I had to raise the values by about 130% to stop that happening on the blown cars I have done.

[Extinct]

Found my problem with the help of Humpin SS :oops:

[TAQuickness]

Yes, I partially agree. Someone with better experience (than myself)tuning trucks should write a better tutorial than this one since it appears to be very incomplete.

This document is very incomplete if someone follows it and then gets a "reduced engine power light" until a previously "untainted" program is flashed back into the pcm.

Maybe more should be added to the disclaimer of this document such as "If you follow only this tutorial, your vehicle may raise a "Reduced Engine Power" code and your vehicle may become virtually unusable until a re-flash of the original tune is made into the PCM"

Maybe you should quit whining and submit your findings so the doc can be revised? Or maybe you should write your own doc?

Seriously, what would you be doing right now if that doc didn't exist?

[BowlingSS]

It worked great for my car.

Bill
:D

[Beer99C5]

LOL hey I joined this club today, I told my buddy to womp on it ( a bit ) for our first Auto VE run (he was driving and I was logging) next thing you know we had no power and limped to the break down lane...he was impressed when I reloaded the untouched tune and we made it home :bash:

Glad to see its not just us. :muahaha:

[Beer99C5]

dfe1 is saying to temporarily set C6101 to max while tuning, and to log DYNAIR so you can create a new C6101 table from DYNAIR plus some percentage;
C6101 gives you a factor of safety in case something goes wrong (MAP/IAT fail causing VE lookup/calc to go wrong...).

OK gonna try this again Friday (wife has off today so the world will revolve around her activities :help2: ), so there are 2 Dyn air PIDs, one of them is SD. Now I saw this and asked Chad of GLMS what the difference was (before I did the first VE logging session) so lets see if I understand correctly. One is measured, one is calc; being the MAF is disabled for the AutoVE.tun that would mean DynAir would be bad info, and DynAir SD would be the one to use being its calculated.

So what I am thinking is add DynAir SD to the PIDs for AutoVE and make a Map for it to try and catch which cells need to be modified in C6101?

Or will changing the C6101 by say 20% from 2500 RPM and up do the trick?

TIA
Beer

[Dirk Diggler]

I would cahgne the whole table by 50% and see if that cures it when you are finished tuning you can build a map and remake your new table

[Beer99C5]

OK done the table change...will give it another shot tommorrow :)

[Beer99C5]

dfe1's table worked for me, did not hit power reduction during logging session

Thanks :)

Beer