Surprise when installing my K&N

[LucifersChild]

So I took off my old nasty air filter in the car i bought about 2 weeks ago to install the K&N airfilter I bought for it. When I took the airfilter off I took a look at the MAS and found out that the top filter was completely ripped off. I know about people "hacking" the bottom filter to try to eliminate fuel cut and make their cars run faster, but the TOP??? Please tell me that nothing too horrible is happening to the car. It already has a big idle surge jumping around a 700 RPM range. I replaced the spark plugs the same day, and 2 of them were pretty dark and 1 was white. I believe it was the 1st cylinder running lean. How much should I worry about this and would the GM MAF be a good investment to correct this problem?

 

[5150DSM]

A GM MAF would be a good upgrade; however, right now, that's not your main problem, your car is running lean...dangerously lean. Personally, I would hit a local junkyard and see if you can grab an upper honeycomb filter there, if not 1G MAF's are cheap and fairly easy to find... Just look in the classifieds on this site. With the upper honeycomb removed, the Karman Vortex Sensor is only reading a very small portion of the air that is entering your engine, in turn, the ECU is only adding fuel correspondent to the air signal it is reading. Because the air signal being read is far below what is actually entering the engine very little fuel (relatively) is being injected. The reason your #1 plug is white is because you were probably experiencing some detonation (pre-ignition) #1 runs the hottest so it shows up there first. I would check the pistons (especially #1) before I drove the car again, there is some chance that you burned it(them). Look for pits or spalling in the surface and for any cracks, real damage should be fairly obvious. Hope this helps. Good Luck!

 

[LucifersChild]

I seriously doubt that the pistons are screwed up, but I will check anyways. The car runs great while at WOT and while cruising, but if I back off the gas it tends to buck a little. I found a green wire just dangling around, I assumed it went to the TPS and hooked it back up and it doesn't do it as much now. I went to a junkyard and tried taking the upper honeycomb out, but I ended up just breaking it. Is it seriously bad enough to burn pistons??

 

[5150DSM]

Ok, when I say "dangerously lean" I mean it. I can't give you the exact percentage but I would say at least 30-40% of the air entering your engine is unmetered, hence much less fuel. It is often said that the engine runs its best right before it fails so don't make performance the sole focus of your analysis. You really need to either replace the upper honeycomb or replace your MAF ASAP, I would not push the car in the meantime. As far as your pistons... it really depends on how lean EXACTLY you are running and for how long, if the pistons are exposed to lean detonation for any significant period of time they WILL fail. I have no idea what the current state of your pistons is but I would check to be safe, you really wouldn't want to slag one or more of them would you? BTW- if you don't believe me, search for references to "lean conditions" or "detonation",I'm sure you'll find plenty of horror stories about melting pistons. Good Luck.

 

[boostboyike1]

Why do people say lean when my car runs rich w honecomb removed>ps.I didnt do it

 

[n0va91TSI]

taking out honeycombs makes the car take in air without knowing to add more fuel. hence running lean

Also to the guy with the broken honey comb.

DONT DRIVE UNLESS NESCESSARY

and you should either jam a rag in the top hole and just use the lower comb or unclamp the BOV return hose and clog the hole from it on the intake and vent your blow off tube to atmoshere.

both will make u run richer

 

[LucifersChild]

Wow, I'm glad I made this post before I really screwed myself over... I tried venting the BOV, but the car always died if I didn't shift gears fast enough, which isn't very safe for driving in traffic. I vaguely remember hearing something about soldering a resistor in one of the wires leading to the ECU from the MAF, which was suppose to make the car run slightly richer. Does anyone know anything about this? In the mean time I guess I will try plugging the hole with a cloth until next friday when the paycheck comes. Damn, I hate getting payed biweekly...

 

[psychlow]

Venting the BOV will only make you run rich between shifts - it can actually cause you to run lean at idle because most stock BOVs leak some at idle creating a vacuum leak (unmetered air = lean).

You can unplug your O2 sensor. It'll go into a limp mode and run rich.

 

[TSi92]

Originally posted by psychlow
Venting the BOV will only make you run rich between shifts - it can actually cause you to run lean at idle because most stock BOVs leak some at idle creating a vacuum leak (unmetered air = lean).

You can unplug your O2 sensor. It'll go into a limp mode and run rich.

Lean at idle is nothing to be scared about... running lean with a load... that's when things melt/break.

 

[LucifersChild]

I've been Paying attention to my Air/Fuel Ratio gauge and it doesn't tell me I'm running lean at all... When I give it gas the bars jump up and when I'm idling they bounce up and down like they are suppose to. What kind of aftermarket performance options do I have to correct this problem?

 

[psychlow]

Originally posted by TSi92
Lean at idle is nothing to be scared about... running lean with a load... that's when things melt/break.

You're still going to run lean when you start off during normal, everyday driving. Any time it's under vacuum, it'll run slightly lean.