Help with Silverado tune

[nfs13b]

Hello all,

I have a 2003 Silverado 2500hd with the 6.0L engine running on LPG... I am getting faults picked up with the EFI Live tool which are:

P0172 "Fuel Trim System Rich Bank 1" EPA ($10) "Powertrain Control Module (PCM)"
P0175 "Fuel Trim System Rich Bank 2" EPA ($10) "Powertrain Control Module (PCM)"
P0302 "Cylinder 2 Misfire Detected" EPA ($10) "Powertrain Control Module (PCM)"
P0300 "Engine Misfire Detected" H ($10) "Powertrain Control Module (PCM)"
C0201 "Antilock Brake System (ABS) Enable Relay Contact Circuit" H ($29) "Electronic Brake Control Module (EBCM)"

In regards to the misfire the car still runs fine and the only reason I know its there is because the programmer tells me it is....

Is anyone able to have a look at my logs and tell me if I have a problem with the tune...

cruise log.efi
cartrailer.efi

This is just a normal driving log on my way home and also when I was towing my car trailer...

Now I dont know much at all about the tuning side of it so any help would be really appreciated..

I have recently changed the spark plugs too and put in new iridiums hoping it might fix up the miss but it didnt..

[schwoch1]

Are you using a multiport setup with your LPG fueling, or are you using a vaporizer before the throttle body and just shutting the petrol fuel injectors off?

Mike

[nfs13b]

Are you using a multiport setup with your LPG fueling, or are you using a vaporizer before the throttle body and just shutting the petrol fuel injectors off?

Mike

Hey Mike,

I am using a liquid LPG setup with 8 LPG injectors installed and the signal piggybacking off the petrol injectors signals

[schwoch1]

Hey Mike,

I am using a liquid LPG setup with 8 LPG injectors installed and the signal piggybacking off the petrol injectors signals

Ok, I was hoping you would say that!!! I have seen some horrible conversions where people just jam a vaporizer before the throttle body than wonder why their plastic intake blew off when it backfired!!
Is this conversion strictly LPG only, not bi fuel? If LPG only, it looks as if you are going to have to do some tuning on the VE tables to get the A/F ratio's back in line so that the engine is not running rich. I also think you are going to have to change the A/F ratio that the computer is commanding/expecting to get everything to work right. Do you have a wideband oxygen sensor? If you are doing a bi fuel that could get a little tricky then. Let me know!!!

Mike

[nfs13b]

Sadly it's dual fuel, it starts on petrol for 30 seconds and then switches to lpg. The only other time I drive it on petrol though is if I run out of lpg then it may go 10km on petrol till I can get some more lpg. If the economy will improve a lot though I am happy to make sure ii fill it up before it runs out.... Although someone once told me there should be a way to make it switch to think it is on liike ethanol and use the flex fuel maps... But didn't say how....

[schwoch1]

Sadly it's dual fuel, it starts on petrol for 30 seconds and then switches to lpg. The only other time I drive it on petrol though is if I run out of lpg then it may go 10km on petrol till I can get some more lpg. If the economy will improve a lot though I am happy to make sure ii fill it up before it runs out.... Although someone once told me there should be a way to make it switch to think it is on liike ethanol and use the flex fuel maps... But didn't say how....

Yah, that throws a little curve in things. Most of the dual fuel systems that I have seen use some sort of control box that is adjustable by the end user to adjust the A/F ration while on LPG. There was a system out there a while back that Moates marketed that had two flash chips in it, so in essence you could have two totally different calibrations inside of one PCM, but I don't belive it was designed for the 1meg PCM's that your truck uses. If you have to be able to have dual fuel options, than I would check with your LPG conversion company and see if somehow they can see what the heck is going on!!!
Mike

[nfs13b]

The conversion company said its all just controlled off the one tune, but they said they put the right size lpg injectors in it to balance against the petrol ones for the different tunes... How about if I drive it on petrol for a bit and log that? And I think I missed a bit earlier, no I don't have wideband o2 sensor in the Silverado :(

[BLK02WS6]

This is just a thought, but could you use a Flex Fuel OS and use a switch connected to the PCM pin for the flex fuel sensor - when you switch fuels, you could use the VE tables for the different fuels provided in the OS?

I don't know anything about LPG, but from the discussion, it seems that any way you could change the fueling would be helpful...

Another thougth was whether or not COS5 was available for your OS - use the nitrous enrichment for your fueling controlled off of a switch??

[schwoch1]

Got a copy of your cal? Maybe flex fuel is an option!!!! I have heard of injectors being 'sized' for the application, but I am not a believer at all in the one size will fit multiple vehicles theory!
Post a copy of your cal if you can!!!

Mike

[nfs13b]

Is the cal the tune? If so here it is attached.... or is it this calz file perhaps?

Or is it:


VIN 1GCHC23U13F222472
Engine 6.0L
Transmission 4L80E
PCM flash 1MB
Operating System 03150003
Calibration N/A
OS ID V3
Cal ID
BCC MOD3
OS Level
Cal Level
Cal file name 03150003.calz
Cal file version 7.94
Cal file date 07 April, 2009
Operating System 03150003 $4F66
Engine Calibration 12577909 $58D5
Engine Diagnostics 12580650 $F69F
Transmission Calibration 12572453 $2A0C
Transmission Diagnostics 12572475 $40FE
Fuel System 12578355 $B3C0
System 12572587 $1B2D
Speedometer 12572529 $CE74