Sputtering under WOT - Thread Revisited

[Hulty]

Hello all,

This thread in the main forum died out in Dec. 2012, but is there anyone out there still dealing with this and/or have figured out a solution?

I'm in the same boat, and I'm looking for suggestions or known fixes. I never use anything less than 91 Oct. and was paranoid enough about the spark plugs that I bought new, gapped all to .028, checked for bound springs in the plug wires, and still can't run a WOT quarter mile without sputtering at some point.

Any help I'd appreciate it as I'm running out of ideas....I'm even tempted to try the whole idea of putting the screen on the CAI, but REALLY don't want to.

Thanks, Hulty.

 

[Eric Smit]

what kind of plugs? I had issues with sputtering using copper plugs. nothing but NGK super massive too many iridium layers in my Sonic.

 

[Hulty]

I went with pure OEM to eliminate any possible variables - Autolite XP Iridium. I was taking no chances, so I got rid of that stupid circular gap tool and bought a proper set of shims to make sure I was exactly .028.

A big THANK YOU to Advanced Auto Parts for telling me the OEM gap was .025"..........MELONS.

 

[Hulty]

I suppose I forgot to mention, I am fully tuned from Trifecta. They said they noticed it on my log, but it wasn't the doing of the tune.....although it had never sputtered previously....nice.

 

[Preloader]

The tune allows higher boost. The pressurized air is more resistant to conduct spark, causing "blowout". Check your coil connection, and confirm that all your spark boots are undamaged and properly installed. There has been a common issue with these boots in which the connector gets c0cked out of alignment during install.

 

[Eric Smit]

get those things out of your car and put NGK in. ****, I have a ton of them with probably 60% life, because I obsessively replace them, if you send me a shipping label.

side note, NGK plugs are stock.

 

[Hulty]

When I called AAP, they didn't even show NGK as an offering because that's my GO TO plug as well.

I had read many of your past posts about the boot wires before doing, so I took great care in everything being perfect after install.

 

[Sonic]

What engine do you have so this can be moved to the proper spot?

 

[rdss]

Moved to 1.4 engine forum.

 

[Eric Smit]

whoops, didn't even notice that. thanks guys.

 

[Preloader]

I believe when he made this thread he hadn't reached his 10 posts, therefore he couldn't post it in the correct category.

Can't be perfect Smit.

 

[Dogz]

Over here in Aus people usually change from NGK Iridium plugs to a standard type NGK plug because the Iridium air gap plugs can't handle high boost. Is this not a common thing over in the US?

 

[Eric Smit]

I believe when he made this thread he hadn't reached his 10 posts, therefore he couldn't post it in the correct category.

Can't be perfect Smit.

oh you know me. it's hard being perfect all the time so sometimes I engineer a mistake to bring me down back a notch into the mortal coil.

 

[Eric Smit]

Over here in Aus people usually change from NGK Iridium plugs to a standard type NGK plug because the Iridium air gap plugs can't handle high boost. Is this not a common thing over in the US?

first I'm hearing about it.

 

[Scot]

You're tuned - what RPM are you sputtering at?

You might have an outlier - lower flow fuel / higher airflow: If it is only at high RPM, you may be going 100% duty cycle on your injectors.

 

[Eric Smit]

if I remember correctly from when it happened to me, as soon as boost raised above 19, RPM was irrelevant.

 

[Hulty]

You've just highlighted another aspect of this that I'm also puzzled by, the corresponding boost at blowout. I've only been running my UltraGauge for about a week and I'm yet to see boost higher than 16. Prior to that it's been so cold that due to air densities I imagine I wasn't even approaching 12. So with that, I was finding the blowout scenario very hard to believe. Thoughts?

 

[Hulty]

Rather than RPM's it seemed to be more of a factor of engine load because I could easily get sputter starting between 3-4K, but only at WOT.

 

[cndctrdj]

I have the same problem. Some days it does it. Some days it doesn't. It drives me crazy at the track and also the reason I can't run good times.
I also noticed it happens a lot less when I roll on the throttle instead of mashing it

 

[Twitch]

same

Happens to me during WOT in temps colder than 25-30 F. I talked to a buddy and says its the injectors. Duty cycle at 100% is ok at normal temps but here in PA with higher elevation and cold temps he recommended 42# injectors and a retune