Ported Stock MAF

**ONEslowLS1** · 04-22-2010, 10:01 PM

I just installed a slp air lid and ported the maf and when i floored the car the service engine light came on. What are these codes and will they hurt my car if i drive it and performance wise?
It threw these codes:
po1404
po151
po131
po157

**Y2KPewterSS** · 04-22-2010, 10:28 PM

http://obdii.com/codes.asp

You can use the link above to check your trouble codes. Porting the stock MAF was a bad idea.

**ONEslowLS1** · 04-23-2010, 10:43 AM

Why is it a bad idea?

**basballny2** · 04-23-2010, 10:45 AM

because the stock MAF works fine, once u start going with aftermarket MAF's and porting the stock you need to re-tune the car and it can cause all kinds of trouble.

**35th-ANV-SS** · 04-23-2010, 11:09 AM

Stocker is good as-is for applications up to 500 or so HP.

**ONEslowLS1** · 04-23-2010, 11:13 AM

Thanks and is it ok if i just de-screen one?

**Cutlass** · 04-23-2010, 11:33 AM

no. leave the stock MAF alone

**pajeff02** · 04-25-2010, 01:53 PM

Any modification to the MAF throws off the fueling. All sorts of people will tell you that they have done this and that to their MAF and their car runs fine. Quoting Greg Banish, a noted GM tuner, modifying the MAF can alter your fueling by as much as 13% if I recall correctly. Essentially, the PCM is interpreting the data from the MAF based upon a known flow calibration. When you alter the flow by de-blading, de-screening or porting the MAF you throw off the calibration.

**sjsingle1** · 04-25-2010, 02:18 PM

is it running richer or leaner?? seems my car has always run rich....even after the maf mod......kn filter..and LT's......when the money train rolls in.....getting a tune

**Y2KPewterSS** · 04-25-2010, 07:22 PM

Porting the MAF leans it out. Adding long tubes makes it richer.

**Firebirdjones** · 04-25-2010, 08:04 PM

I have a stock MAF on one, and the other has ported ends that bolt to the stock housing.
The stock MAF was easy to tune. The other car took a bit of tuning in the MAF tables to get it decent.

If you really really wanted to play with the MAF, rather than removing screens, and grinding on the housing and possibly ruining it,,,,,I'd personally just bolt on the ported ends that come without the screens.
If you don't like it or you have problems, it's easy to switch it back to stock ends. Either way, tuning is needed.

I thought the ported ends were still available?? Maybe not.