270 mcx turbo nytro running like crap

[Thedoityouselfguy]

after pounding my way up the whoops at revy last weekend my nytro all of a sudden started running crappy just as i pulled up to the cabin. I shut it off. checked plugs, they looked fine.....replaced them anyway. appears to be getting a good supply of fuel. spark on all cylinders. ran diagnostic test......all injectors are ok. I checked the all the little vacuum lines.......all good. Whole intake side pressure tested good. and whole exhaust side tested good. What am I missing here? It turns over very slow.......only fires if you give it a little gas. Wont idle....it dies. but if you hold throttle steady it will maintain regular rpms....although still runs very rough. if you grab the throttle it struggles to pick up speed or rpms then once the turbo spools, it seems to normally boost and run fine in the higher rpm range. I am stumped!

 

[bourgon]

Check your battery had a old car that would do the same thing changed battery and was fixed!

 

[JP.]

Check your battery had a old car that would do the same thing changed battery and was fixed!

There you go.....fixed


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[Thedoityouselfguy]

Well I guess I am not lucky enough to have the problem b something like a battery. Turns out it is a head gasket.....I can feel blow by from one cylinder to the next when I crank it over. What does mcx use for the head shim and head gasket? Also where can I buy them? Thanks

 

[rknight111]

Darren at E&S in Fort Saskatchewan

 

[Thedoityouselfguy]

Ya I am going to call him again tomorrow. What do you guys think of the alpine stainless steel shim? I was only running 12# of boost when the shim and/or gasket blew so I am wondering if there is something a little better than what was in it.

 

[MRFUSION]

We use only the Stainless head shims now, had a couple MCX head shims fail between the cylinders, they are aluminum. Make sure you didnt have an injector fail on the aux injectors in the plenum, had a few of those fail too, will fill a cylinder with fuel. Luck
Shad

 

[Thedoityouselfguy]

We use only the Stainless head shims now, had a couple MCX head shims fail between the cylinders, they are aluminum. Make sure you didnt have an injector fail on the aux injectors in the plenum, had a few of those fail too, will fill a cylinder with fuel. Luck
Shad

Can you elaborate a bit for us on the bad plenum fuel injectors? I noticed a slight stutter when I grab the gas.....I think I read some guys say injector issues may cause that but I never really seen the relation off failing injectors contributing to a blown head gasket. I am thinking maybe a failed ignition coil could lead to over fueling a cylinder causin blown gasket perhaps but not failed injector. More info please.

 

[MRFUSION]

The failing injector will stick open but wont cause the head shim to fail, it will overfuel and maybe hydro lock your engine, it was just something to check. As far as the head shim failing it is usually caused my detonation from either poor fuel or the control box not kicking in the aux injectors. The stutter when hammer is usually from transition when the aux injectors kick in, most MCX kits do that. Do you have a AF gauge?

 

[Thedoityouselfguy]

The failing injector will stick open but wont cause the head shim to fail, it will overfuel and maybe hydro lock your engine, it was just something to check. As far as the head shim failing it is usually caused my detonation from either poor fuel or the control box not kicking in the aux injectors. The stutter when hammer is usually from transition when the aux injectors kick in, most MCX kits do that. Do you have a AF gauge?

Ok I get ya on the injector thing now thanks for that. The kit was originally installed with the oem torque to yield head bolts and upgraded to the 270 kit later so I am assuming it was just a matter of time before the gasket/shim failed. Definitely be throwing arp studs in now. And I am actually waiting on my af gauge to show up in the mail any day now. Is there a way to fix that stutter somehow with a different fuel map or injectors or something by any chance? It's a real throttle robber when you need it. FYI its a rear mount as I am sure you already know given the symptoms. Thanks

 

[MC Xpress]

We have steel MCX shims in stock in Prince George. Detonation in my experience is the only that takes out an aluminum shim. A bad batch of fuel was probably the culprit. The 270 kit pushes the limits of pump fuel so if the fuel isn't up to snuff they will knock.