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Discussion Starter #1
I've got an 01 with a knock and excessive black smoke under throttle. Hoping it's the injectors and not a rod, wrist pin, etc. I've tried everything listed in all the Torque Pro threads i could find & still can't get balance rates to read correctly. Have the ELM custom configuration string set to atz. Have tried changing the Preferred OBDII protocol to J1850 VPW 10.4k baud. Have tried checking the "Use Alternate OBDII Header" setting. Balance rates still read anywhere from -423 to 0. Also tried with a mechanic buddy's Snap On Modis scanner & all balance rates read 0 on it. No codes present. Can the injectors be so bad that balance rates won't read?
 

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Try this...I have not

Yet to use Torque Pro, but maybe this will help. Kinda fuzzy, but search on poster for better resolution.
 

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Discussion Starter #3
Yeah, I've done everything he suggest in that post, along with several dozen more threads across multiple diesel engine forums with no success. I've ordered a new OBDII dongle, just in case the cheap one I bought isn't working properly (last thing i could think of). Really curious why balance rates all read 0.0 on the Snap On.
 

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If nothing you have hooked to the OBD2 port will show up with balance rates, then there is something triggering the ecm not to give that information. Is the truck at a dead idle? Is the idle elevated for any reason? Is the truck up to operating temperature and at idle? If the truck isn't at an idle, the balance rates will not read. If the actual rail pressure is more than a little off from what the desired rail pressure is, then it will not show balance rates because it thinks there is something commanding rpm other than idle. Also, if the truck is not up to operating temperature, then the balance rates are not correct and could cause you to throw money at new injectors even when they aren't needed.

My LB7 does this at times, and usually its a glitch in the fuel pressure-regulator sticking, lift pump over-pressuring at times. Just odd things that happen that mess with the ecm. Usually a blip of the throttle, or a shut down/restart will calm it down to where its supposed to be, or just let it sit and idle for a few minutes and try to look at them again
 

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Discussion Starter #5
Was attempting to read at idle with the engine warmed up. Interestingly, I also wasn't able to get the rail pressure pid to read; just showed blank. I couldn't find a pid for desired rail pressure.
 

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Discussion Starter #6
I know it's been a while, but thought I'd post & let everyone know it ended up being my ELM adapter. I bought the slightly higher-priced one from BAFX & was able to get it to read my balance rates. Still not able to get a rail pressure reading, though???
 
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