multiple sensor issues

[klin7757]

okay so i recently noticed after doing the coffee cup mod that that my boost pressure had dropped from 11psi to 9 . i gave the boost controller a turn and it was back in the 11-12 range. while driving on the highway i noticed that the power was very inconsistent. i stepped on the gas and hit fuel cut. i turned down the boost a little, but the car was limp. i checked trouble codes and now have codes 11 and 22 crank and knock sensors (explains the lack of power). i'm curious to know how this occurred and if i really need to replace both sensors. this all seems to be directly related to the coffee cup, so is it possible that the MAF sensor has something to do with this? any help is greatly appreciated.

[BXSS]

I had about 5 codes pop up when the vac. line going to the MAP/exchange sol. popped off.
Put the hose back on & all was well.

I'd say check than everything is connected well & clamped on tight.

[vrg3]

If your car is running, don't worry about the crank sensor code.

The knock sensor does sometimes just go bad, especially the original design.

Do you have the MBC hooked up along with the stock boost control, or have you capped off the stock boost control solenoid? If it's the former, a knock sensor problem would explain the change in boost level.

[klin7757]

i've capped off the nipples on the boost controll solenoid that used to run to the turbo nipple and the wastegate, but left the line coming from the bottom of the solenoid and tapped it into the coffee cup (i'm not sure if this was nessisary, but figured why not). i've pressure tested my ic setup as well and it was holding fine when i did it. as much as i turn the controller i cant get the boost to raise above 9. with the solenoid out of the picture i'm not really sure why. i suppose replacing the knock sensor should be first on the list and we'll see what happens after that.

[vrg3]

Leaving that hose on the bottom there is fine. You could also cap it off on both ends though.

If you can't get more than 9 psi of boost, either the turbo's shot or you have an abnormal restriction in the intake or exhaust.

Check the color of the connector on the knock sensor. If it's gray, you have the old failure-prone knock sensor. The redesigned sensor has a white connector.

[klin7757]

i just checked and the knock sensor does have a grey connector, so it probably did just crap out. as for the boost issue i thought the turbo might be shot. i did see some smoke coming from it the other day, but put on the eye muffs and pretended it was nothing. i'm sure that the intake track is clear and fairly positive that the exhaust doesn't have a blockage, so most likely the turbo. looks like i'm in the market for a td04 and an 06 ic. thanks for the info!

[denver_whitest185]

the rear cam seal next to the turbo tends to get cooked pretty good and leak after awhile, so it might be that. do you know if they seals in the heads were ever replaced?

i mean, a td04 would be a good upgrade, but it would suck if it doesn't solve the problem. i would check for shaft play on your turbo before you assume its the culprit, and inspect the area for any oil/gunk buildup

-Ted

[klin7757]

yeah i actually did the rear cam seal about 3 months ago, so it's most likely not that. i already got a 06 wrx ic and a td04 would be easier to mate to. they're fairly inexpensive and will do the job until i make the cash for a td05 and the resulting new transmission.