2002SS339

I descreened my MAF a few months ago, it ran good no problems. Now when I punch it at around 80-90 mph it feels like it gasp for air like (Lag) or something, Check engine light comes on and also I hear I guess it would be KR. Should I buy a gm new MAF for 151.00 (GM supplier Disc) or spend a few more dollars and get a 85mm MAF or ???

Please help!!!

unit213

Does it sound like someone's shaking a coffee can full of bb's? If so, you're definitely pinging. I doubt that is the direct result of removing the MAF screen. My Z28 used to ping. I switched from Sunoco 94 octane to Amoco 93 octane. No more pinging. Weird, but true. Lots of LS1's have this problem.

2002SS339

Exactly like that! I use Exxon super but I will try Sunoco but I havent seen that one here in San Antonio or could I try Oct. booster?

horist

Octane booster is crap... it raises your octane by points not whole numbers... when they say it'll raise it 3-5 points it'll raise it from 93.0 octane to 93.3-93.5 octane... and after a while of running it you'll have a nice red tinge on your spark plugs... See if you can borrow a friends stock MAF... the descreened MAF may be leaning you out just enough that the engine pings

unit213

Let me guess, it only happens above 5,000rpms right? horist might be right. You could be running a tad bit lean. The temperature plays a big role too as well as the fuel you run. Don't run octane boost. It's junk.

99 Black Bird T/A

iTrader: (4)

Shine a light into the MAF and check and make sure none of the wires in the MAF are broken. There are five very thin wires. With ill fitting lid sometimes a bug or something can get in and break a wire. Also if you just cleaned your air Holley air filter check for oil on the wires. That can cause strange things too.

GuitsBoy

iTrader: (4)

Five wires? I only count three on the ones ive seen, but good advice otherwise.

01PEWTERTA

Just curious, but if there is oil on the MAF wires, how would you clean it safely (besides VERY carefully) ?

SScam68

iTrader: (20)

burning oil?

Have you made a catch can yet?

2002SS339

Yes, I burn oil about 1qt every 3k miles. Yes, it starts to ping around high 4k rpm to passed 5k rpm, I really never paid attention to that because I dont know what to look for. I cleaned my filter a few weeks ago, didnt see anything like oil, but I did not check the MAF but I will this weekend.

SScam68

iTrader: (20)

2002SS339

It sounds like the same problem a friend is having. He has an 02 Z. He also has autotap and said he was getting knock in the upper RPMs.

He also mentioned his car consumed a lot of oil.

We decided to do the "PVC" mod to see if it would alleviate the problem.

goto
www.installuniversity.com
www.ls1info.com
www.slowls1.com/pcv.htm

you'll see writeups on what I am refering to.

Your not going to find oil on the filter or on the MAF, the oil gets introduced from the PVC behind the throttle body. You need to remove the throttle body and run your finger on the inside of the intake. Your finger will more than likely have oil on it.

The oil being consumed lowers the octane level of the fuel and can be attributed to knock.

Hope this helps.

Frank

2002SS339

Looks like I will have a busy weekend. Thanks, alot for your time.

99 Black Bird T/A

iTrader: (4)

Thanks, your exactly right...I was typing in a hurry and should have said. There are three very thin wires suspended between the five ribs.

Colonel

[logic]He said his CHECK ENGINE light comes on...and the question is...WHY? That would be the first thing I would find out. Fix whatever's causing the DTC and you might return your performance.[/logic]

BTW, running a little lean will not cause a check engine light.

2002SS339

check engine light is the MAF code. what should I do with the MAF besides what I have planed (mentioned above) for this weekend?

Viper

iTrader: (6)

Electrical contact cleaner on the wires, wipe it down with q-tips, making sure no q-tip fuzzies are left on the wires.