OVER REVVING IDLE AND CUT OUT

[beejay820]

Hi,
I previously posted about my problems a couple of months back, but no one seemed to be able to respond with a suggestion. So I am posting again with a few more details, as I haven’t been able to get the issues rectified.

Firstly, when I first start the car, it revs to 2500 to 3000rpm. It does settle down to normal cold start rpm after about 10 seconds, or if I blip the throttle. It remains at around 1600rpm for much longer than it used to and it eventually settles down to normal idle. Otherwise, the car runs pretty much normally, just hanging on occasion when I come to a stop.
Here’s the weird thing though: If the car moves, as in rolls down hill at more than 5mph without touching the accelerator, it revs up to about 2500rpm then up and down until I stop. This happens backwards and forwards, but if I remain static, the revs remain at around 1600 for a few minutse until it settles to 750.

Secondly, when I put my foot down and the boost reaches about 15psi, the engine suddenly cuts out and the EML comes on. This seems to have lowered from the 20psi cut out level a couple of months back. I replaced the boost controller and the MAF sensor, because the CEL logged a boost control fault, nothing changed. After three or four trips, the EML goes off.

Any thoughts would be appreciated.

[beejay820]

Originally Posted by beejay820

Hi,
I previously posted about my problems a couple of months back, but no one seemed to be able to respond with a suggestion. So I am posting again with a few more details, as I haven’t been able to get the issues rectified.

Firstly, when I first start the car, it revs to 2500 to 3000rpm. It does settle down to normal cold start rpm after about 10 seconds, or if I blip the throttle. It remains at around 1600rpm for much longer than it used to and it eventually settles down to normal idle. Otherwise, the car runs pretty much normally, just hanging on occasion when I come to a stop.
Here’s the weird thing though: If the car moves, as in rolls down hill at more than 5mph without touching the accelerator, it revs up to about 2500rpm then up and down until I stop. This happens backwards and forwards, but if I remain static, the revs remain at around 1600 for a few minutse until it settles to 750.

Secondly, when I put my foot down and the boost reaches about 15psi, the engine suddenly cuts out and the EML comes on. This seems to have lowered from the 20psi cut out level a couple of months back. I replaced the boost controller and the MAF sensor, because the CEL logged a boost control fault, nothing changed. After three or four trips, the EML goes off.

Any thoughts would be appreciated.

Barometric Pressure Sensor.