225 TT loss of boost
Hey everybody.
I have had an issue with this TT I bought ever since I purchased it..
Originally the car had an aftermarket manual boost controller installed in it in place of the stock N75 valve. It created a heck of a lot of boost, but caused issues with surging, so I removed it and bought a new n75 Valve.
Even with the new N75 and a new DV, the car still has this nagging problem though.....
Most noticeably going up a hill, plant your foot into it and you get 14 pounds of boost for maybe 2 seconds......Then it flattens out and sits away at 10 pounds. Sometimes though, it will only hold 10 pounds of boost for a few seconds, then go to 5 pounds and be utterly gutless....
You can correct the problem by backing off throttle, cutting boost for a brief moment, then get back on the gas again. Then it will repeat the cycle, and loose boost again.
I had it apart the other day when I was replacing the valve cover gasket, and only noticed the following "wrong"
-Line to the PCV is aged and kinked almost shut (ordered a new one)
-Hose from DV to the charge pipe has a small crack in the end (but checked and found no leak).
Plugged My MaxiDas into the car and it's not tripping any codes..
All I can think of is a MAF sensor throwing the car into limp mode, or a boost leak somewhere.
Thoughts anybody??
Thanks!
Josh
p.s, AMU motor, if that makes a difference??
I have had an issue with this TT I bought ever since I purchased it..
Originally the car had an aftermarket manual boost controller installed in it in place of the stock N75 valve. It created a heck of a lot of boost, but caused issues with surging, so I removed it and bought a new n75 Valve.
Even with the new N75 and a new DV, the car still has this nagging problem though.....
Most noticeably going up a hill, plant your foot into it and you get 14 pounds of boost for maybe 2 seconds......Then it flattens out and sits away at 10 pounds. Sometimes though, it will only hold 10 pounds of boost for a few seconds, then go to 5 pounds and be utterly gutless....
You can correct the problem by backing off throttle, cutting boost for a brief moment, then get back on the gas again. Then it will repeat the cycle, and loose boost again.
I had it apart the other day when I was replacing the valve cover gasket, and only noticed the following "wrong"
-Line to the PCV is aged and kinked almost shut (ordered a new one)
-Hose from DV to the charge pipe has a small crack in the end (but checked and found no leak).
Plugged My MaxiDas into the car and it's not tripping any codes..
All I can think of is a MAF sensor throwing the car into limp mode, or a boost leak somewhere.
Thoughts anybody??
Thanks!
Josh
p.s, AMU motor, if that makes a difference??
Disconnect the MAF sensor and see if it makes any difference to performance. If performance improves replace the sensor. If it doesn't improve it could be a boost leak, visually check for cracks, collapsed hoses ,loose connections etc
or this link explains a little more
hope this helps
Rob
Scotland Uk
or this link explains a little more
hope this helps
Rob
Scotland Uk
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