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[Stealthmode]

  Went to dyno, everything good. Drove car a couple days, and it had a weird sputtering on occasion between 5 and 8k rpm, in random gears, and sometimes not. When I would hear sputtering, I'd get out of it, back on it, and it would go fine.

  As the days go by, sputtering becomes pretty constant, while getting out of it and back into it would work.

  The other day, it now sputters anytime I hit 5200rpm, in any gear, pedaling doesn't help.

  When it was occasional, I thought it was an ignition issue. Changed dist., new iridium plugs gapped to .019, same shit. Then it went to all the time at 5200, so I'm thinking vtec issue.

Checked wiring from solenoid to ecu. Good.
Changed vtec solenoid only (same body). Still sputtering.
Checked oil level.
put the missing o-ring between head and center cam cap.
Took off vtec body, changed gasket and made sure it wasn't seized.

  It's not the ignition, my tune can't just change from dyno to now, and with the gradual increase in periodic sputter to constant sputter at 5200, I was thinking obstruction of oil to vtec shit. Nothing.

I want my fucken boost back. 

[Eggylshatch]

fuel pressure?  You running aftermarket fpr?  I'm sure you have at least a walbro in tank eh?  What do your plugs look like after the sputtering?

[Eggylshatch]

and you did a wire tuck right?  How sure are you of the handy work there?

[Stealthmode]

  Running the fuel lab regulator, it reads normal at idle, but I haven't checked to see if it's acting funny up top. Walbro hp, 1000cc RC injectors.

  Running slowly up in rpm, at 5200, every fucken time it's sputtering. I'm gonna try to get it on the dyno today to see wtf is going on.

[patsmx5]

What brand and viscocity oil are you running? And how is all your shit plumbed now with the sandwich plate?

[stealthiskey]

disable the VTAAK and try it above 5200?

[Stealthmode]

I'm running amsoil 10-30, with the gauge and turbo off the Tunertoys fitting, and the head with a -6 off the sammich plate.

Just talked to dyno guy and we'll be on it tomorrow. Vac driving sucks ass.

[Eggylshatch]

maybe vtec isn't engaging but the computer is still switching you to the vtec map?  How is your oil pressure?

[SDRAWKCAB]

Vtak pressure switch?

[Stealthmode]

maybe vtec isn't engaging but the computer is still switching you to the vtec map?  How is your oil pressure?

  That's what I was thinking, but I haven't noticed any abnormal drop in pressure. Don't recall what the pressure was up top, but I can't get there now. Idle and driving hasn't had a drop.

[Joseph Davis]

Check VTEC screen for debris.  Do it before you drive it again.  Don't drive it if there's more than a very few tiny flakes.

[Stealthmode]

Check VTEC screen for debris.  Do it before you drive it again.  Don't drive it if there's more than a very few tiny flakes.

Took off vtec body, changed gasket and made sure it wasn't seized.

Gasket included the screen check.

[chris]

Unplug vtec solenoid see if 5200 rpm problem occurs still

[Stealthmode]

Thinking about it, what's that gonna do? If I think vtec isn't working, what would change by unplugging it? 

[j.h.christ]

Thinking about it, what's that gonna do? If I think vtec isn't working, what would change by unplugging it? 

to see if it's the engagement that's fucking your mojo up. if it revs smoothly... well, you can surmise the rest.

[Stealthmode]

I think I might just be a Cornelius.

Unhooked vtax solenoid. It went past 5k no problem, but no boost. WTF?

Take it home, find dangling charge pipe.

Fix charge pipe and hook up the vtax for the fuck of it. One rip and it goes great, boost, no stutter, great.

Way home from store, no boost, just stutter. Look at charge pipe, and it's dangling again.

I think the neighbors are tired of hearing me start the car over and over at 1am, so I'll do a good fix on the pipe in the morning, and maybe head to the dyno anyway.

[chris]

Vtec doesnt need to work to rape vtec motors to ungodly rpm's it just wont make any power.

[Eggylshatch]

You should post porn (Wifemode?) to make up for newb-ness

[t_cel_t]

You should post porn (Wifemode?) to make up for newb-ness

agreed

[HiProfile]

Fix charge pipe and hook up the vtax for the fuck of it. One rip and it goes great, boost, no stutter, great.

There still seems to be a problem, as a leak there shouldn't do that on a speed-density system. Last time I harmlessly blew a charge pipe off (imagine a stock z6 and t3/t4 with no boost gauge & big rip in WG line), it simply blew off and careened into the hood. I could still rev it out. However I also street tuned every part of the map before when it was NA. Vtec was engauging, since I could preceive the .025 dB increase in the sohc's sound.

If the solenoid is being told to engauge, but not playing ball, that shouldn't cause that much problems. You need your timing & fuel to be WAY off before you go nowhere, and I doubt you have S2S2 cams or something. Try another solenoid, or rig it so you can test it. Then look at your low VAC part of the tune for oddities...