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Discussion Starter · #1 ·
Took the wife and snake to best buy this afternoon to snag a DVD. Trip there was fine, car was driven very moderately. Never got into boost. On the way home leaving the parking lot I slipped the clutch at a pretty low RPM, as I released the clutch the engine stuttered a little bit. I thought it was my clutch at first. I then tried getting on the gas from a roll in 2nd... Again the car stuttered! After playing with it for a mile or two I've determined there is something wrong as far as boost control. Any time I make a throttle movement in such a manner as to cause the boost gage to fluctuate, the car stutters! Almost sounds/feels like the boost bypass is venting pressure any time you get into vacuum.

The car only has 7500 miles on it and the mods are listed in the sig. I did make one change the other night though... I received the re-manufactured MAF elbow for my DC. I've had the original DC on my car for almost a year and the only problem I had was a rough idle. Once I replaced the old elbow with the re-designed elbo I noticed a mush smoother idle. Is it possible that a vacuum leak in my CAI could cause this condition? I used the sensor safe RTV that Mr. Demolet sends with the kit. I've visually inspected all the junctions on the DC and they all seem clean/air tight.

Any ideas or has someone else seen this before?

Thanks

U.M.
 

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Sure sounds like some kind of vacuum leak. Have you tried to put things back to original and check it out? Hard to say from here, but it might be your best bet right now. Then work your way back.
 

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Discussion Starter · #3 ·
predator said:
Sure sounds like some kind of vacuum leak. Have you tried to put things back to original and check it out? Hard to say from here, but it might be your best bet right now. Then work your way back.
That's what it's acting like. Many others say it's the DC. I say horse crap! So I re-orientated the MAF to the 12 o'clock position by installing the redesigned DC inlet pipe. I've had my DC on for 6000 miles and the only problem encountered was a rough idle. The car ran fine for the first 3 or 4 driving cycles after installation. Since replacing the DC inlet tube my idle is smooth again, stays right at 750RPM's. If the MAF sensor had gotten contaminated during the DC install I should be getting an SES light, right? If I had misaligned the inlet pipe to the down pipe (although it's not misalined, I've checked all parts) this would only allow unfiltered air into the MAF. The MAF would still be reading the air flow rate. If there was a leak AFTER the MAF, then maybe... but again I've checked and it's good and secure.

Another theory is my FRP sensor is bad. There are 2 other folks who have described the same symptoms I'm expirencing and they both had a bad FRP sensor. I did pull the vacuum line off of the FRP sensor and it was free of gas. I disconnected the FRP itself and removed it from the fuel rail. Everything appears to be fine. Reconnected the battery and all the lines, took for a test drive and problem is still there. I'm guessing it's a bad FRP sensor, any other thoughts?

U.M.
 

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Sounds like you have done a thorough check. Have you considered taking the DC off completely? Just a thought, but might help further isolate the problem in your diagnosis. Other than that maybe an analyzer to see if any codes are being put out. I don't know what they would be. Lastly....I don't know what an FRP sensor might cost, but if your suspicion is there and you don't have access to an analyzer you can take a stab at it. Sorry I can't be more help technically. Just things I would consider after all else has been checked.
 

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You might try to put the MAF at 9 o'clock and check for leaks, if you did not have it there before. What is difference between the old end the new DC ?

AMB
 

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Discussion Starter · #6 ·
AMB said:
You might try to put the MAF at 9 o'clock and check for leaks, if you did not have it there before. What is difference between the old end the new DC ?

AMB
The orginal DC left the MAF sensor at the stock 9 O'clock position. The newly redesigned DC inlet tube rotates the MAF about 90 degrees so the sensor is at the 12 O'clock position.

I still think it is a fuel delivery or vacuum issue myself.

U.M.
 

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Just saw your post in another board. Looks like everyone is pointing down the same road. I would agree that it might be best to take it in to Ford to make sure all is well......or spend $45 for the sensor and see what happens.
 
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