Hi, we have an 07 mcs which was totally stock except for an alta bov at the time this problem first began. I went to accelerate coming off an exit ramp and the car felt like the turbo wasn't kicking in. After downshifting and hammering the gas, upshifting and hitting the gas again a couple times it was back to normal. A few days later something similar happened and it has been doing it off and on more and more often lately. At one point car threw a p115d code for the AFM, which i believe was due to the BOV venting to atmosphere.

Recently added unichip and HKS bov. Still having the problem, can last anywhere from 30 seconds to 5 mins or so, it usually seems to come back. Anyway, Now with the hks which has a secondary, smaller vent for low pressure and opens sooner than the old bov i realize it is making SOME pressure, but very very little

Im not sure if that is the "limp" mode that people speak of and what i should be looking for. It seems to be happening more and more though and happens at random, so i want to get an idea of what it is before i remove the unichip and bov to take in under warranty.

Car has 28k miles and only gets 93 octane. Previous owner had the car until 16k and it was almost all stop and go city driving and never taken over 4k rpm so i seafoamed it but imagine it could use a little more in the way of a decarb

thanks in advance

 

I have heard of cases where this oil pipe becomes clogged up due to infrequent oil changes and the lack of lubrication causes the snail to malfunction and fail....Hopefully not your case but something to look as it is somewhat of a "common" problem.

Part no.6 here.

 

That is your whole problem. Get rid of it. Seriously.

I can't believe those are still floating around.

you can close this thread now.

 

I would have to agree but it was happening before we ever had the unichip. Im thinking its some sort of limp more or a problem with the wastegate actuator. Just wish it was not an intermittent issue cause thats making it harder to figure out

 

I'd put the car back to stock including no bov and see what happens.

 

Before you go back to stock check the tube thats underneath the air box that moves the boosted air around somehow. Its connected and held in place with a plastic clip that can get hot and break. My clip broke and the tube popped off causing my car to loose all power and shut off. It would start but immediately shut off again. Yours may be loose and needs to be fixed but hasn't popped all the way off yet which is why you loose boost, but then it comes back

 

I'm with MotorMouth....

You can do yourself a favor, by taking off the BOV and don't even try to use the UniChip.

Clear codes, then re-diagnose.

Two mods that notoriously cause nothing but issues...seems silly to even ask what the issue may be while they are still on your car.