Hesitation/Bucking with DSM AFC

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Knox Joe

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Ti MSP
Well I have had the AFC on for a while and everything was fine. I've always ran the supermap.

I installed a CAI, and FMIC. Now for some reason as I'm going to accelerate the car bogs down real bad, then catches back up. The a/f is rich when it happens, but no more than usual.

I've checked every vac line, and all the intercooler pipes, and everything seems fine. It only does it sometimes too, it's very intermittent.

Oh, and sometimes my boost guage gets stuck at zero, even though the turbo is spoolin, and there is vacuum.
 
How much boost are you running and what are your afrs throughout boost? Is your maf relocated? Pointed in the right direction after install?
 
Maf is installed correctly, I'm spiking 7.5 holding 6.5. AFRs are from 10.0 12.3 under power.
 
I have the same problem I am going to get the car retuned on the fly tomorrow. Might want to gap your plugs to .028. BTW did you get the car dyno tuned ?
 
No dyno tuning. The spark plugs are NGK coppers, and they are gapped at .028, lol.

Unsolvable problem?
 
Suffering from fuel cut. Need to go to Ken to see if he has a solution.
 
But it happens at low RPM as I'm accellerating, before even a couple pounds it happens.

I could see if I was revving the s*** out of it, but I'm not. I'll be going and I'll just slighty depress the gas to accel and it does it. So I'm thinking it's not fuel cut.
 
Knox Joe said:
But it happens at low RPM as I'm accellerating, before even a couple pounds it happens.

I could see if I was revving the s*** out of it, but I'm not. I'll be going and I'll just slighty depress the gas to accel and it does it. So I'm thinking it's not fuel cut.
Click to expand...


I have the same problem, i replaced the air box with a filter, custom exhaust and Apexi AVC-R BC, around 10 psi, i wanna drive it off a cliff because i can't pass cars when i put my foot down from low rpm cause it boggs, the car actually momentarelly floods cause it runs crazy rich, but it's pissing me off
 
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S.A.MSP said:
I have the same problem, i replaced the air box with a filter, custom exhaust and Apexi AVC-R BC, around 10 psi, i wanna drive it off a cliff because i can't pass cars when i put my foot down from low rpm cause it boggs, the car actually momentarelly floods cause it runs crazy rich, but it's pissing me off
Click to expand...


the difference is that you dont have a tuner. he does and the a/f is still giving him trouble.
 
Even at a slow speed the the hesitates. I have ordered the fuel cut defender from speed ciruit for $75.00.
 
Are you using the stock bypass valve? Might consider putting the stock airbox back in just to see if that helps in an effort to see where the problem lies.....
 
Loose IC to TB coupler was the problem. Got a T-bolt clamp and it's all good now.

Why do we pay nearly a grand for a FMIC and get the cheap clamps that blow off?

the clamps would cost retail about $30-$50, for a performance shop it would be next to nothing.

A suggestion for the FMIC manufacturers out there, give us T-Bolts.
 
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Trying loading a "no change" map into the AFC and see if the same problem persists. If it does it might be either wiring related to the AFC or something else totally unrelated. Make sure that the vacuum line going into the AFC is leak free as well.
 
CustomMSP said:
Trying loading a "no change" map into the AFC and see if the same problem persists. If it does it might be either wiring related to the AFC or something else totally unrelated. Make sure that the vacuum line going into the AFC is leak free as well.
Click to expand...

Read my above post. It was a leaky coupler from the cold pipe to the throttle body. It eventually blew off, so I had to get the t-bolt clamp.
 
I have the DSM and my car still boggs, then i disconnect the battery to reset then all is well for like two days to a week, then it happens more right after i fill my tank, i run 93 because my gas is payed for (nana) does anyone have a leaner fuel map or somewhat of an idea on how to get rid of this problem
 
S.A.MSP said:
I have the DSM and my car still boggs, then i disconnect the battery to reset then all is well for like two days to a week, then it happens more right after i fill my tank, i run 93 because my gas is payed for (nana) does anyone have a leaner fuel map or somewhat of an idea on how to get rid of this problem
Click to expand...


You have to run 93 no matter what.
 
yea i know, it feels great when the car isn't bucking but i wanna drive it off a cliff when it does
 
quickest, cheapest fix: Don't boost before 3000 rpm!! haha. My car always did this and it pissed me off so much i thought i was gonna lose it. But just dont ream it out in upper gears from under 3k and you'll never think about it again, these cars handle soooo great anyways between 3500-5000; it's a tiny cracked-out Japanese engine that will go and go, but needs to be run fast (rpm's i mean) to get at the power and smoothness. It's designed that way.
 
S.A.MSP what kind of clamp do you have on your hot pipe?


I imagine you're using a silicone coupler?
 
Knox Joe said:
S.A.MSP what kind of clamp do you have on your hot pipe?


I imagine you're using a silicone coupler?
Click to expand...

the hot pipe is the one from turbo to intercooler right, if so then i am still using the stock pipe, as for the other pipe (intercooler to intake mani) it is held together silicone couplers.
 
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