A4 ALH not accelerating beyond 75mph

My sons new ride-A4 ALH feels like it's not accelerating past 75mph. I just had the T Belt changed & intake cleaned. My prior A4 seemed to have better acceleration as well with stock set up. Any ideas? I did get a glow plug code. Thanks

One possibility is the intake being plugged up with gunk. Another could be if the timing was not set properly after the timing belt changed.

Who did the timing belt change?

second that... the cam timing is probably off and maybe the injection timing too. does the engine sound more cluttery or louder ?

Turbo not boosting properly? I know my mk3 seemed to have trouble clearing 75 mph and it turned out to be a cracked vacuum line.

Get a vagcom and check IP timing and if you have the capabilites check the cam timing as well. Also pop off your EGR valve and check your intake. Test your N75 valve with vagcom (cycle it) and check the turbo actuator (make sure it is freely moving). Look for cracked/disconnected vacuum lines.

Could also be a bad MAF that reads low, resulting in restricted fueling. VAG-COM should enable that to be confirmed by comparing requested and actual MAF.

Dave

accel issues

Thanks guys! We found a cracked vacuum line. I guess it doesn't take much to mess up performance. Replaced the thermostat too. It ran cold according to my scan guage. Better now & should help the fuel useage. B