Hi,

My wife's Fiesta gets warning light and limp mode when going uphill. We've taken it into the Ford dealership 3 times and still no fix. Any suggestions? Details as follows.*

When going up hills (or even relatively modest inclines), the warning light on my wife's 2010 Fiesta 1.6 diesel comes up (on a daily basis) and the car goes into limp mode. If she stops and restarts the car the fault will clear...*until the next bloody hill. I have connected a bluetooth ODB2 to her car and I see a P0299 (turbocharge underboost) error.

We took the car into the Ford dealership and they said the (suprisingly expensive) intercooler needed replacing. My wife asked if that would "definitely" fix the problem and the dealership said yes. However, got the car back and the problem was still occurring.*

Back to the dealship and they cleaned an air sensor they said was covered in oil. Got the car back and the problem was still occurring.

Back to the dealship and they replaced the air filter that they said was clogged up. Got the car back and the problem was still *bloody* occurring.

To be fair to the dealership, intermittent faults are harder to fix and they haven't charged us after the (suprisingly expensive) intercooler. But we are getting sick of the hassle.

Does anyone have any suggestions?

Thanks

Brett