* * hit 10psi it would cut out real bad

[cruisintalonawd]

Ok so my girlfriends car is a 94 awd talon. She has FMIC, new Evo3 16g, AFPR, 510cc, a/f gauge and boost gauge, vr4 fuel pump, 3" full exhaust with header and a KN air filter.
Now the other day we were doing practice launching and when she hit 10psi it would cut out real bad so we tried turning up the fuel being that it felt like "fuel cut" and at 60 psi at idle it still didnt help so we changed the plugs and wires, still nothing. Today we did a BLT and still nothing so now im stumped about what to do....can you please help???

Also we did a compression test and all 4 were 140 ish
and it has a bit of rough idle

 

[RC_slow_dsm]

Sounds like a boost leak to me, have you checked for any?

 

[cruisintalonawd]

We checked for boost leaks and there was a small one at the throttle body, but we fixed it and it made no difference.
We had the logger hooked up and it did show up to 40 counts of knock at times.

Just changed the coil pack and not it will go to 15psi and start cutting out

 

[redyute1]

i have the exact same problem but my car will not revv past 4k changed everything but the wires ,but really my knoch sensor seems to be bad cause the gumy stuff on it seems to have melted and is soft, so i think it is affecting my ignition timing so till i get a new one i will have to live with it but still unsure that this is my problem though,keep us posted if you get it fixed.May be you can run a log to see what your ignition timing is doing during that time,cant log cause i still need a cable for my logger

my bad over looked where you said you had 40 counts of knock,see the thing is the ecu sees all that knock it will retard timing and if you still have the boost solenoid it will aslo cut down on the boost to protect the motor so you may wonna get that knock taken care of.Who knows maybe a faulty sensor or your tune is off

 

[cavillac]

sounds like you need to fix the knock or replace the sensor..

 

[cruisintalonawd]

sounds like you need to fix the knock

That would help wouldn't it.

 

[Defiant]

You're hard against fuel cut. You're pulling in much more air than the ECU will allow, and the motor is desperately trying to save itself by turning off the gas supply.

 

[habitatguy187]

You're hard against fuel cut. You're pulling in much more air than the ECU will allow, and the motor is desperately trying to save itself by turning off the gas supply.

So would a hacked maf cause this? Cause my car is doing the same thing around 5k rpms

 

[cruisintalonawd]

You're hard against fuel cut. You're pulling in much more air than the ECU will allow, and the motor is desperately trying to save itself by turning off the gas supply.

So then what does the ecu shut off? Injectors or the fuel pump. how do we get around it

 

[Silverpearll]

My car did this before I replaced the capacitors in the ECU. Also check your spark plug gap to make sure they are not to big, causing blowout.

 

[delta448]

Do you have any compensation for the larger injectors?
When you did the BLT, how long did it take to bleed off and what pressure did you use?
Are your plugs properly gapped to 0.028"?
Are they NGKBPR6ES?
Do you like anchovies on your pizza?
Have you thought about replacing the knock sensor?
Paper or plastic?
Did it idle without any counts of knock?
Do you want fries with that?
Have you checked the timing?
Any CELs?
Have you ever done whippits with the unburnt fuel in the exhaust while at a stoplight?
Is there spark on all cylinders?
Any arcing under the hood while idling at nighttime?
If you attach the plug wires to your nipples and bump the starter does it turn you on?
Is your BOV recirculated?
What do you have the base fuel pressure set to with the vac line off?

You're hard against fuel cut. You're pulling in much more air than the ECU will allow, and the motor is desperately trying to save itself by turning off the gas supply.

 

[cruisintalonawd]

Do you have any compensation for the larger injectors? 21 psi

When you did the BLT, how long did it take to bleed off and what pressure did you use? fairly long with 15psi

Are your plugs properly gapped to 0.028"?yes

Are they NGKBPR6ES?yes

Do you like anchovies on your pizza?no

Have you thought about replacing the knock sensor? changing to a known good one

Paper or plastic?paper

Did it idle without any counts of knock? nomal driving

Do you want fries with that?sure

Have you checked the timing?no timing light or do you mean cam timing

Any CELs? lights never came on

Have you ever done whippits with the unburnt fuel in the exhaust while at a stoplight?huh??

Is there spark on all cylinders?yes

Any arcing under the hood while idling at nighttime?dont thing so

If you attach the plug wires to your nipples and bump the starter does it turn you on?nice
try but there is spark going to the plugs

Is your BOV recirculated?yes

What do you have the base fuel pressure set to with the vac line off?40

 

[knochgoon24]

Do you have any compensation for the larger injectors? 21 psi

What are you tuning with? AFC?

 

[delta448]

Do you have any compensation for the larger injectors? 21 psi

I meant tuning-wise. You can't just drop in bigger injectors, they have to be offset somehow so the ECU opens them for a shorter amount of time. You need at least a SAFC or MAFT.

When you did the BLT, how long did it take to bleed off and what pressure did you use? fairly long with 15psi

Try it at 25psi, and time it with a watch or a clock with a second hand.

Do you like anchovies on your pizza?no

Aww, come on man, you're missing out.

Have you checked the timing?no timing light or do you mean cam timing

I meant what you're referring to as cam timing. But it wouldn't be a bad idea to find out base ignition timing too, especially since you 1G guys have that nice adjustable CAS. A parts store might let you use one if you can limp the car there, might even be able to talk them into a couple of other tests if they think you might buy something.

If you attach the plug wires to your nipples and bump the starter does it turn you on?nice
try but there is spark going to the plugs

That's the point.

What do you have the base fuel pressure set to with the vac line off?40

You need to set it lower, like around... say roughly 37.5psi.

 

[cruisintalonawd]

I meant tuning-wise. You can't just drop in bigger injectors, they have to be offset somehow so the ECU opens them for a shorter amount of time. You need at least a SAFC or MAFT.

Try it at 25psi, and time it with a watch or a clock with a second hand.

Aww, come on man, you're missing out.

I meant what you're referring to as cam timing. But it wouldn't be a bad idea to find out base ignition timing too, especially since you 1G guys have that nice adjustable CAS. A parts store might let you use one if you can limp the car there, might even be able to talk them into a couple of other tests if they think you might buy something.

That's the point.

You need to set it lower, like around... say roughly 37.5psi.

were short on budget thats why were arent using a tuning device, and were figure that 510's were better then 450's at 21 lbs of boost.(she wants dsmlink and i have her talked into a MAFT when she gets link) thats with a line running straight to the wastegate. once our other awd is done in the driveway I,ve got to pull her car in and fix the intercooler and change the knock sensor. The has been set up the same way since she put the 16g on and was fine until about a week and a 1/2 ago.