Spoolerr

Even with my boost sensor unplugged i still get a small miss here and there at wot, sometimes in normal driving/ cruise. Just like it cuts out completely for a second then goes again. (jerks or bucks)

First i thought it was boost cut, but its not very consistant with rpms or load..

its an S4Tii with S5Tii motor

thanks
brandon

gxlbiscuit

you cant be serious........ im sorry to sound like an ******* but thats boost cut.... you need a fuel cut defender. this is common rx7 knowledge if you dont know this you should not be messing with your car.....read up a bit then come back to kick ***....as of now you are working to have your *** kicked by a blasted engine...

Spoolerr

So even tho my boost sensor has been tricked using a bleeder valve to see only around 5 ish psi my VAF will still pull fuel to to rear rotor?

this isnt a light miss, this is both rotors cutting out for a second then comming back in. I dont have a boost controller, i didnt mean to raise it or **** with it yet but i have a full 3" no cats and strait muffler.

even when i am around 4K at like actual 6 psi (clibs to nine, boost creep) i still get it sometimes, and its not the 3800 hesitation i dont think, this is a cutting out very randomly

staticguitar313

iTrader: (2)

you need to do it right, no amount of ghetto rigging will work, your putting your engine in danger do you have money for a re-build? buy a FCD

MARTIN

People like you **** me off... talking out of your ***... Can you see that he said he unplugged the boost sensor... If its unplugged, the computer cant read boost, and therefore doesnt cut fuel.... this is common rx7 knowledge and if you dont know, you shouldnt be giving advice...

As for the random miss, I suggest checking/changing your plugs and/or wires... This happend to me a while ago and I tracked it down to that..

gxlbiscuit

doh retract statement i went back read it again i see he said"its not boost cut" DOH!!!!! anyways i hope i can keep pissing you off since its so easy..... if i make a mistake i try to go back and correct it...

gxlbiscuit

plugas and wires do some dumb **** when old...inconsistently also attack any and all grounds.. its just good juju.... get an fcd

MARTIN

Its not about making a mistake, if you woulda just said its fuel cut, I woulda reminded you of what he wrote. But you had to start talking ****, and riding on this guy, when your info wasnt even correct..

gxlbiscuit

whatever you say, its not worth my time, yours, nor fixing his issue...

NZConvertible

Unplugging the MAP sensor on a Turbo is a really dumb idea. If you're unlucky you'll blow the engine...

Plugs older than six months should be replaced if you're getting a miss, as should original plug leads. For me it was a failing lead.

RETed

I dunno why people are against the idea...
All the FC guys in Japan used to do it all the time.
Before proving the boost sensor has nothing to do with fuel delivery, I thought it was a crazy idea too.

Then we found out that all the boost sensor does is retard ignition timing...
So it has nothing to do with fuel delivery.

It's fine for testing.
The original poster only goes up to 9psi.
Unplug the boost sensor, and the stock ECU auto defaults to about 5psi.
If you're running premium octane (which you should in the first place), the several degrees of advance isn't going to hurt anything.
Besides, this is purely for testing!

If it's still bucking like that, I would suspect the TPS is out of spec.
Check to see at full open that the TPS isn't going over 5.5k-ohms.


-Ted

MARTIN

he already did that.

NZConvertible

I never said it did. I'm well aware that ignition timing is the issue here, not fuelling. While you'll probably get a way with it most of the time, factors like high ambient temps, a heat-soaked intercooler, a bad batch of fuel, or a combination of these on top of ignition timing not retarded as much as normal could cause detonation. That's why I specifically said "If you're unlucky..." I didn't say damage was inevitable. Maybe the stock ignition curves are conservative enough to get away with it, but would you guarantee that under all circumstances?

I bet many of those Japanese you're referring to also have FMIC's and fuel controllers, both of which offer added protection from detonation. But we're talking about a mostly stock car.

So nothing ever goes wrong in testing?

gxlbiscuit

umm did i see advance????