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MAF problem on Whipplecharged '97.

nakona

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nakona New Member

nakona

Posted
Posted

I have a friend who owns a 1997 Chevy Pickup that has the 350 Vortec with a WhippleCharger and the Granatelli MAF.

 

When he goes over 5000rpm the "Check Engine" light comes on and it throws a MAF MALFUNCTION code. Both stay until the computer resets.

 

 

Anyone ever run across this problem?

 

 

My inclination is to have him just get an F-Body MAF from an 93-97 LT1 car, but I wanted to ask around first.

 

I do know that Granatelli has a rep for problems and that they often run 7-10% lean.

 

I also wonder if this is just a re-programming issue...?

 

 

Any thoughts?

99Silver6.0 Senior Enthusiast

99Silver6.0

Posted
Posted

Get rid of that Granatelli! That thing is not worth the troubles. They do make for a pretty lean condition. Im not sure about interoperability of the f-bod MAF versus the truck MAF. Id just get the truck MAF and call it good.

tmf6902 Senior Enthusiast

tmf6902

Posted
Posted

My dad had a suburban with that engine, and a whipple....at highway speeds sometimes the check engine light came on, or when climbing a mountain or something. He had it checked out and the mechanic couldn't find anything really happening. it would go off after you drove around for a while???? The only thing I know that was wrong once is that it was running lean.

ECMProgrammer Enthusiast

ECMProgrammer

Posted
Posted

Depending on what the trouble code is, you could have several problems.

 

1. Maf out of range codes can set if airflow is beyond the sensing limits

2. Low or high MAP codes can set if values do not correspond to PCM presets

 

If you can find what the trouble code is--someone here can help you out.

 

Lyndon

www.ecmprogrammer.com

americanmuscleman Enthusiast

americanmuscleman

Posted
Posted

Do you have your stock MAF that you could install and try?

 

I would ditch the Grantelli MAF. The whipple program is designed for a stock MAF, and adding an aftermarket one probably leans out the A/F mixture which could damage your engine.

 

If you want to run the aftermarket MAF, I'd get the truck professionally tuned.

 

Good luck!

nakona New Member

nakona

Posted
  • Author
Posted

OK, more info.

 

We put the stock MAF back on and the problem improved but didn't go away.

 

The code that is coming back is for a high MAF frequency, which means that the MAF is maxing out.

 

On an OBDII vehicle, that will set the code, throw the light and cut the injector pulse width.

 

There's supposed to be a MAF translator that comes with the whipple kit, but the kit came with the truck and we don't even know what to look for in terms of whether or not the translator is even there and if it is, is it functioning?

 

 

So that leaves me with two basic questions:

 

1) Has anyone done OBDII conversions on these trucks?

 

2) Does anyone do programming for them? I don't mean just burning a chip, I mean programs that you upload to the PCM via a laptop.

 

Thanks.

02denali Enthusiast

02denali

Posted
Posted

i think you need some programming for it to work correctly.

the granatelli maf i had went to 29.98

the stock maf went to -----------28.92

the Zo6 maf goes to -------------34.82

i am having great luck with the Z06 maf. and i do have it tuned in to.and yes i had it tuned with all mafs and the Z06 is helping me the most. :cheers:

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