ZR-1 Net Registry Forums - View Single Post - 91 ZR-1 Cutting Out Under Load

08-21-2006

GM uses short-term(integrator) and long-term(block-learn) fuel numbers. They are as they say, fuel maps of different time lengths. The short-term numbers will be very bumpy and jump all over the place, even at idle. This short-term map varies fuel for any reason such as a lead foot, hilly route, large load, a/c,vacuum leak, etc. It instantly adjusts with (in GM's case) above the number 128(the mean desired fuel delivery point) representing lean or adding fuel, and below 128 as rich and subtracting fuel. The block learn or long term numbers are a smoothed out picture of this fuel delivery. The same 128 number representing the optimum mean point. Above 128 and the PCM is needing to add fuel over the long term and vice-versa.

O2's - L- .10 to .69 R- .10 to .74 What is the rate of fluctuation? Slow/Fast?
Block Learn L- 136 R- 130 You are adding fuel, not that much though
Integrator L- 127 to130 R- 128 to 130
TPS .44 At idle or key in the run position should be around .54 volts

When testing injectors, remember that checking the resistence is only 1 of the things that can fail. You can have it also fail by leaking, spray and flow issues.

Consider spending the ten bucks on a fuel filter, make sure you have line wrenches for the job.

08-21-2006	#23
Jeffvette Guest Posts: n/a	Re: 91 ZR-1 Cutting Out Under Load GM uses short-term(integrator) and long-term(block-learn) fuel numbers. They are as they say, fuel maps of different time lengths. The short-term numbers will be very bumpy and jump all over the place, even at idle. This short-term map varies fuel for any reason such as a lead foot, hilly route, large load, a/c,vacuum leak, etc. It instantly adjusts with (in GM's case) above the number 128(the mean desired fuel delivery point) representing lean or adding fuel, and below 128 as rich and subtracting fuel. The block learn or long term numbers are a smoothed out picture of this fuel delivery. The same 128 number representing the optimum mean point. Above 128 and the PCM is needing to add fuel over the long term and vice-versa. O2's - L- .10 to .69 R- .10 to .74 What is the rate of fluctuation? Slow/Fast? Block Learn L- 136 R- 130 You are adding fuel, not that much though Integrator L- 127 to130 R- 128 to 130 TPS .44 At idle or key in the run position should be around .54 volts When testing injectors, remember that checking the resistence is only 1 of the things that can fail. You can have it also fail by leaking, spray and flow issues. Consider spending the ten bucks on a fuel filter, make sure you have line wrenches for the job.