I had the "Engine Service Now" message appear on the dashboard during a long motorway drive last night. The MIL light was not on.

Came with a very noticeable engine derate.

Car is a 1.0 Ecoboost in a 2015 Ford Focus estate.

I made it home ok with no other obvious issues.

When I got home I plugged in my OBD reader and found the following historic errors in the memory.

 

This morning the error message had gone and the car was back to full power. 

Any ideas? 

 

 

 

If the MIL is not on then it's unlikely that a generic OBD code would have been set.  Try Forscan instead.

If it's an underboost fault, you should be able to replicate that easily enough with a hard pull onto a motorway slip road or similar.

P0420 is fairly standard for 1.0 EcoBoosts now.  The cats do wear out over time.  Sometimes Cataclean will give you a few more months out of the old one.

Thanks for the reply TomsFocus.

I did the new oil service reset routine this morning (switch ignition on with accel pedal and brake pedal pressed for 2mins) which seemed to complete ok.

I wanted to eliminate that incase it came back again.

What will Forscan tell me that the Car Sanner App didnt?

I've never used Forscan before, can you recommen a thread or youtube video to get me started?

Generic code readers (even the very expensive professional units) do not read all or any of the Ford specific DTC's. There are basically two types of DTC, the standard ones common to all vehicles, and the manufactures specific DTC's which are unique to each vehicle maker.

FORScan is basically cloned version of the Ford dealers equipment and can do most (but not all) of what could be done at a Ford dealer.

FORScan:

On 4/7/2024 at 8:59 PM, unofix said:

FORScan (for use with Windows Laptop) : https://forscan.org/download.html

It's what many Ford owners use including some Ford technicians.

• vLinker FS, cable for laptop: https://www.amazon.co.uk/Vgate-vLinker-Adapter-FORScan-MS-CAN/dp/B0952P4MLP

OR

• OBDLINK EX, cable for laptop: https://www.amazon.co.uk/OBDLINK-EX-FORScan-OBD-Adapter/dp/B081VQVD3F/ref=sr_1_5

For diagnostic use only:

• vLinker FD, for android phone: https://www.amazon.co.uk/Vgate-Bluetooth-vLinker-Scanner-Diagnostic/dp/B08H82WC8L
• vLinker FD+, for iPhone: https://www.amazon.co.uk/Vgate-Bluetooth-vLinker-Scanner-Diagnostic/dp/B08H8JHWP2

 

Ive ordered this one for my IPhone

https://www.amazon.co.uk/Vgate-Bluetooth-vLinker-Scanner-Diagnostic/dp/B08H8JHWP2

Also downloaded the free  "FORsanViewer"

Any tips on where to start to investigate my issue once the Scanner arrives? 

You need the paid for version, the free Viewer is very limited. see the following, Comparison of FORScan applications,

 

Hello, i don't know if this trick is functionnal on mk4 :

 

 

Just wanted to send an update on this:

Since I did the oil service reset routine I havn't had the "Engine Service Now" message back and the engine also hasn't derated anymore (over six weeks now)

Checked N75 turbo solenoid? Any leaks?