Granatelli programmable MAF sensor
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From: Taxme, Ohio
Granatelli programmable MAF sensor I had my 01 Z28 dyno'd with a wideband a/f ratio reading. The result was 14 through all three pulls. Two with a hpp powertune installed and the final with it removed.
I noticed 2 DTCs when removing the hpp tune that had not tripped the SES. 41 and 36, so I think they may have happened during the first pulls but stupid of me not to have scanned before the dyno.
I want to bring the a/f down to 12.7 - 13.2 I think. I've been told that the hpp powertune didn't work because with my a/f at 14, the car was getting it's performance from the low octane table(s).
What are my options in order to get the correct a/f?
Granatelli sells a programmable maf sensor kit that will lie to the pcm.
http://www.granatellimotorsports.com/gmmafamatic.htm
Is this worthwhile or should I dump the hpp and get a custom tune?
Things are a little complicated with the DTCs which have not emerged since being cleared after the 2nd dyno pull. I have driven the car only about 50 miles since. The car is rarely driven and I have noted a few occurrences of a cat smell. Not on the dyno though and not since before the run.
Again, I'm looking for advice on all these things. Money is a bit of an object but I know I've got to spend something....
My apology for adding a thread that probably is repeated. The forum is huge to search and apparently at full load....
thanks
I noticed 2 DTCs when removing the hpp tune that had not tripped the SES. 41 and 36, so I think they may have happened during the first pulls but stupid of me not to have scanned before the dyno.
I want to bring the a/f down to 12.7 - 13.2 I think. I've been told that the hpp powertune didn't work because with my a/f at 14, the car was getting it's performance from the low octane table(s).
What are my options in order to get the correct a/f?
Granatelli sells a programmable maf sensor kit that will lie to the pcm.
http://www.granatellimotorsports.com/gmmafamatic.htm
Is this worthwhile or should I dump the hpp and get a custom tune?
Things are a little complicated with the DTCs which have not emerged since being cleared after the 2nd dyno pull. I have driven the car only about 50 miles since. The car is rarely driven and I have noted a few occurrences of a cat smell. Not on the dyno though and not since before the run.
Again, I'm looking for advice on all these things. Money is a bit of an object but I know I've got to spend something....
My apology for adding a thread that probably is repeated. The forum is huge to search and apparently at full load....
thanks
Thread Starter
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Joined: Oct 2005
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From: Taxme, Ohio
Is it my MAF that is the problem here?
I understand what you mean but I'm not ready to pay $700 for a tuning program when I don't know that I will be able to understand it in the short term. It strikes me that the learning curve is a major one. I have tunercat for my Lt1 and I don't dare use it until I get some background. A dyno tune is big money for a one time shot and I'm talking to a send away tuner right now, the most economical solution if it works out. I'm grateful for any advice and hoping the thread doesn't die out before I can get enough input to make a good decision. I figure I'm missing out on 10-20 hp until my wideband number goes down.
thanks
I understand what you mean but I'm not ready to pay $700 for a tuning program when I don't know that I will be able to understand it in the short term. It strikes me that the learning curve is a major one. I have tunercat for my Lt1 and I don't dare use it until I get some background. A dyno tune is big money for a one time shot and I'm talking to a send away tuner right now, the most economical solution if it works out. I'm grateful for any advice and hoping the thread doesn't die out before I can get enough input to make a good decision. I figure I'm missing out on 10-20 hp until my wideband number goes down.
thanks
What are the codes that are in? Those numbers don't make sense - those are not SES codes. SES codes start at 101 and go up.
My point was that tricking the PCM is not the way to properly tune a car. The tables need to be tuned with a wideband to get them all correct - particularly true with more mods.
What mods do you have?
*Edit - I looked at your sig - you shouldn't have problems with your limited mods. There is a chance that the HPP3 did something to your PCM or you have some other mechanical/sensor problem causing the lean condition with the power programmer tune removed.
My point was that tricking the PCM is not the way to properly tune a car. The tables need to be tuned with a wideband to get them all correct - particularly true with more mods.
What mods do you have?
*Edit - I looked at your sig - you shouldn't have problems with your limited mods. There is a chance that the HPP3 did something to your PCM or you have some other mechanical/sensor problem causing the lean condition with the power programmer tune removed.
Thread Starter
TECH Resident
Joined: Oct 2005
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From: Taxme, Ohio
Originally Posted by BLK02WS6
What are the codes that are in? Those numbers don't make sense - those are not SES codes. SES codes start at 101 and go up.
My point was that tricking the PCM is not the way to properly tune a car. The tables need to be tuned with a wideband to get them all correct - particularly true with more mods.
What mods do you have?
*Edit - I looked at your sig - you shouldn't have problems with your limited mods. There is a chance that the HPP3 did something to your PCM or you have some other mechanical/sensor problem causing the lean condition with the power programmer tune removed.
My point was that tricking the PCM is not the way to properly tune a car. The tables need to be tuned with a wideband to get them all correct - particularly true with more mods.
What mods do you have?
*Edit - I looked at your sig - you shouldn't have problems with your limited mods. There is a chance that the HPP3 did something to your PCM or you have some other mechanical/sensor problem causing the lean condition with the power programmer tune removed.
The DTCs are P0041 and P0036. According to my DTClookup program these translate to:
O2 1 bank sensor 2 signals swapped w/ O2 bank 2 sensor 2 (P0041)
HO2S bank 1 sen 2 heater circuit (P0036)
The battery went flat prior to the dyno run. I had replaced the battery but those codes may have been generated during the bad battery era or they came into being during the first 2 dyno pulls. The third pull did not produce these codes and I have driven the car 50 miles and there are no DTCs present.
I realize the PE tables can be adjusted to correct the moderately lean WOT condition. I'm wondering why the MAF is telling the PCM that there is less air entering the system or if there are other conditions that produce less fuel than is being commanded.
The Granatelli Maf-a-Matic IS a bandaid but to me, so is tweaking the PE table but I'm willing to do either one rather than throwing parts. Perhaps my injectors aren't at peak or my MAF is coated with k&n air filter oil but the near 330 hp tells me I'm close to being good.
I have contacted a PCM programmer and he wants me to be certain my a/f ratio is continuing at 14:1. This means another session at the speed shop. He's concerned that if he fattens the a/f I may end up running rich.
thanks
Im Haveing A Simlar Issue With My H\c Swap And A Modfied Maf Although I Dont Believe Im My Case The Maf Is The Prob Id Be Intrested In Hearing How You Fix Your Prob..
Not To Hijack But My Prob Is My A\f Won't Come Down On A Dyno Below 15:1
Could Be A Signs Of A Damaged Maf?
Im My Case I Have A Modded Slp Unit With The Resistor Removed And 6.0l Tables In Programed In The Pcm The Maf Has Worked Fine For A Year But After The H\c Swap I Can Seem To Get Back To A Proper A\f So Now Im Thinin Mabye The Maf Was Damaged During The H\c Swap??
Not To Hijack But My Prob Is My A\f Won't Come Down On A Dyno Below 15:1
Could Be A Signs Of A Damaged Maf?
Im My Case I Have A Modded Slp Unit With The Resistor Removed And 6.0l Tables In Programed In The Pcm The Maf Has Worked Fine For A Year But After The H\c Swap I Can Seem To Get Back To A Proper A\f So Now Im Thinin Mabye The Maf Was Damaged During The H\c Swap??
