Hi after owning Mercedes for last number of years I now consider myself a ford man and now own a fiesta and focus both 1.6 tdci.

Got a problem with the fiesta which is 2005 zetec climate, bought the car just a few weeks ago it had a number of modifications including straight through exhaust, dpf delete, k+n air filter and a remap though know little details of work carried out, when I bought it the car had two problems noticed very low power at low revs and EAC fail came on if driven hard (usually when revs got to about 3500) disconnected MAF sensor which improved things so replaced MAF sensor and now performs really low revs but still have the EAC fail, I purchased an ODB connecter and have just plugged it up to laptop using ForScan I’ve determined the fault to be P0234-62 which seems to be relating to Turbo Overboost Condition also says Additional Fault Symptom: signal is below Minimum Threshold.

So I have a few questions firstly I think it would be wise to understand whether I am indeed getting to much boost pressure or whether there could be a problem with the sensor that’s providing the reading but after searching I am unclear to what this sensor is and the location of such?

Secondly if I find I am getting too much boost pressure is there anyway to change the tolerance to allow for this assuming that it isn’t significant enough to pose a serious risk to engine and components.

Thirdly if readings are correct and there’s no way or unadvisable to allow the over boost how can I reduce this, I’m thinking adjustment of the actuator arm?

Any help or guidance would be greatly appreciated.

I know this email does not really help, and I don't know the answers to what you are asking. But I note you say 'dpf delete'.  2005 Fiestas never had a dpf. It was approx. 2009 that Fiestas got dpf. (I know 1.6tdci Focus had them earlier than that)