Common questions

What should LLY balance rates be?

What should LLY balance rates be?

GM states that balance rates should be no more than plus or minus 4 (+4/-4) in park at operating temperature. It is important that injectors are tested at normal operating temperature, from low idle pressures all the way up to full load pressures (as much as 29,000 psi).

Are there any problems with the LLY Duramax?

In terms of LLY injector problems, GM had sorted out the internal failures with the 2004 ½ redesign, but the LLY Duramax would occasionally exhibit a trouble code for the injectors, but in most cases it turned out to be an issue with the injector harness rubbing through and causing a short or open in the wiring.

How many versions of the Duramax diesel engine are there?

All told, there are six different iterations of the Duramax diesel engine: LB7, LLY, LBZ, LMM, LML, and L5P spanning from 2001 to the present day. Each version of the engine has its own issues and quirks, and some are less problematic than others.

What makes a Duramax LB7 diesel so special?

The introduction of common rail injection powered by the Bosch CP3 injection pump made the LB7 Duramax stand apart from other diesels of the day with excellent power and efficiency.

Why is my Duramax diesel engine not working?

The trucks computer keeps track of how much fuel needs to be added or subtracted from each individual cylinder to make the engine run smoothly, and this value is called the balance rate. If one cylinder is contributing too much or not as much as the rest, the cause is usually a bad injector and the cure is a replacement.

In terms of LLY injector problems, GM had sorted out the internal failures with the 2004 ½ redesign, but the LLY Duramax would occasionally exhibit a trouble code for the injectors, but in most cases it turned out to be an issue with the injector harness rubbing through and causing a short or open in the wiring.

All told, there are six different iterations of the Duramax diesel engine: LB7, LLY, LBZ, LMM, LML, and L5P spanning from 2001 to the present day. Each version of the engine has its own issues and quirks, and some are less problematic than others.

The introduction of common rail injection powered by the Bosch CP3 injection pump made the LB7 Duramax stand apart from other diesels of the day with excellent power and efficiency.

The trucks computer keeps track of how much fuel needs to be added or subtracted from each individual cylinder to make the engine run smoothly, and this value is called the balance rate. If one cylinder is contributing too much or not as much as the rest, the cause is usually a bad injector and the cure is a replacement.

Author Image
Ruth Doyle