Ok my car have been tuned two weeks ago... when the car was on the dyno there was a kind of misfirng problem when the car was at idle. When we were removing the #2 cylinder plug wire, while the car was running, it wasnt affecting the idle at all, well the weird sound wasnt changing... so we knew that the problem was on the #2 cylinder. Full throttle pulls were not an issue cuz it was running pretty well at wot.

But like on the dyno... when I boost on the street it begin to do this weird sound of a car running on 3 cylinder and sometimes it stalls... This morning I took the car for about 20km and I did boosted at all and the car was running just fine. Just before taking the last corner before my job I did a solid pull and just after the pull at the next stop the car began to run really weird bop bop bop bap ...

So my tuner is at 2 hours of drive from my house so he told me to change my distributor, cap, and wires to be sure, I did it but it didnt change anything... I even tryed some new plugs.

Im under the impression that when I boost the car the injectors open up and when I let the gas off one of the injectors still open and make one cylinder really rich...

Is it possible ??? my injectors are brand new from last summer and didnt run this winter, Precision 680cc.

Is there anything else to check ?

Oh and when the car gets cold and I restart it... it run fine...

Thanks for the help !

Mat

 

anybody ?

 

might want to change a new set of spark plugs & check the resistance of the plug wire. What spark plugs are you using?

 

I doubt that the injectors is the problem. If the injector sticks or get stuck, they are stuck open, flooding your whole cylinder with fuel. Your car sounds like a ignition problem (dist., ignitor, cap, wires, plugs, etc.). If you changed everything and the problem is still there, it's time to do a compression test. Maybe your cylinder #2 is dead.

 

you can always switch out injector #2 with another to see if it follows... then put it back

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by green_GSR &raquo;</TD></TR><TR><TD CLASS="quote">I doubt that the injectors is the problem. If the injector sticks or get stuck, they are stuck open, flooding your whole cylinder with fuel. Your car sounds like a ignition problem (dist., ignitor, cap, wires, plugs, etc.). If you changed everything and the problem is still there, it's time to do a compression test. Maybe your cylinder #2 is dead.</TD></TR></TABLE>

lol I will do a leak down test but I really doubt that its a mechanical issue... the car run fines when hes cold...

its really a weird problem... maybe its just the tunning...

 

sounds like a blown head gasket and when it heats up the presure is going to spray coolant into the cylinder and cause it to sound like a dead cylinder.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by porsche997 &raquo;</TD></TR><TR><TD CLASS="quote">might want to change a new set of spark plugs & check the resistance of the plug wire. What spark plugs are you using?</TD></TR></TABLE>

my tuner insisted to use BKR8 ... instead of the BKR7ES so 1 step colder... but I reinstalled my 7 range and it doesnt helped...

damn Im fu... tired of those problem on my car... I have everything done right and Ive put all my energy to done it right.

 

Does it only do it when your car is hot?
Do you have any ign on the car like msd?
Does it do it when it is damp out or wet/raining?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by underpressure02 &raquo;</TD></TR><TR><TD CLASS="quote">Does it only do it when your car is hot?
Do you have any ign on the car like msd?
Does it do it when it is damp out or wet/raining?</TD></TR></TABLE>

yes it worse when the car is hot... I run a MSD sci with a Blaster ss coil ( the square one )

the rain doesnt affect the problem...

 

did you check all your wire espically the ones going from the dis down to the external coil?

Also did you try swapping out a new ICM? I know on my last car when it was warm it would act up almost like the coil was breaking down then shortly after that my ICM went.

 

yeah all the wiring have been double checked... I even tryed to run the car with a OEM coil and it was the same thing...

what is a ICM ?

 

It could be a failing injector driver in the ECU.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by yellowturbo &raquo;</TD></TR><TR><TD CLASS="quote">

what is a ICM ? </TD></TR></TABLE>Ignition Control Module

 

BUMP for an answer b/c im having the same problem wit my car