: Throttle Stumble... comming out of it



SoCalV
05-07-05, 09:26 PM
Anybody experiencing a throttle stumble comming smoothly out of the gas at from steady state 2-3k RPM or light accceleration comming out at same RPM range? Intermitent but annoying. Running a cold air intake with K&N filter and a B&B Cat Back resonator.

slow35th
05-07-05, 09:53 PM
Which Cold air Intake?

Dreamin
05-08-05, 12:39 AM
Did you descreen your MAF?... that's a common symptom. Or it's the intake...

lawfive
05-08-05, 11:13 AM
Lately I'm stumbling a little when cold. Not running rough at all, just when I step on the gas the first couple of times, there's a hesitation and for a second it feels like she's not going to go. After a minute or two, everything's fine.

StealthV
05-08-05, 11:18 AM
Lawfive, cold as in the coolant temp is below 131 degrees? If so, there's a good chance your VE table is off in your tune - probably needs more fuel.

wildwhl
05-08-05, 11:46 AM
lawfive -

With the stock Maggie tune...and some of the tunes since, I can confirm that the stumble might be caused by the VE table being off as SteathV suggests above. I've only had it happen, as Rick suggests, at low coolant temps (i.e. not fully warmed up). I no longer have that problem :sneaky:

SoCalV
05-08-05, 11:51 AM
Excuse my ignorance here but what is "descreen"? I don't know the model on the cold air intake as it was on the car when I got it. The plastic tube with the 90 degree bend connecting the manifold to the MAF looks to be stock. An inch from the MAF it connects to a fabricated box that holds the K&N filter. Any comments appreciated!

StealthV
05-08-05, 11:57 AM
From your description, you either have a LPE or MorePerf intake kit. My hunch is the MorePerf - look for a cut in the rubber connection at the MAF, filter and divider panel area.

wildwhl
05-08-05, 12:42 PM
$1 says cut filter as Stealth describes.

Dennisscars
05-08-05, 12:49 PM
:worship::worship::worship::worship:
:worship::worship:StealthV
:worship::worship::worship:

slow35th
05-08-05, 12:52 PM
Excuse my ignorance here but what is "descreen"? I don't know the model on the cold air intake as it was on the car when I got it. The plastic tube with the 90 degree bend connecting the manifold to the MAF looks to be stock. An inch from the MAF it connects to a fabricated box that holds the K&N filter. Any comments appreciated!

I bet Stealth V has found your answer but can you take pics of the air box?

Descreen is when the screen is removed from the MAF (usually a not good idea)

SoCalV
05-08-05, 09:58 PM
OK, pulled the K&N filter, MAF and plastic tube going to the intake on the engine. Unless it had a misaligned clamp letting air in, there are no holes in the hardware. It's an '05 and every connecting point is supple and not brittle at all. No cracks. The plastic tube between the MAF and Engine looks stock to me. Clamps at the connectin points of engine and MAF have machined cut outs to line up properly etc. Clamp on the K&N is different. It's not a round plastic pipe by any means except up at the engine end. Turns oblong on the way to the MAF. There's a horizontal divider inside in the end close to the MAF. Looks like it lines up with the same horizontal divider on the MAF? Sorry for the no photos. My sync for my camera phone is on the blitz right now. Will report any success with reclamping the hardware. Thanks for the observations for sure.

SoCalV
05-08-05, 09:59 PM
Forgot to say screen was intact too.

wildwhl
05-08-05, 10:09 PM
:hmm:

StealthV
05-08-05, 10:35 PM
Since everything appears to be intact, the next plan of attack would be to clean the MAF sensor wires with an aerosol electronic cleaner (available at an autoparts store) to remove potential K&N oil contamination.

StealthV
05-08-05, 10:58 PM
CRC Brand
QD Electronic Cleaner*

*HRE wheels not included :)

Dreamin
05-08-05, 11:02 PM
the next plan of attack would be to clean the MAF sensor wires remove potential K&N oil contamination.

My thoughts exactly.