Hi and greetings from Finland.

 

I've tried asking from Finnish forums for help, but no luck there.

 

Car is 2007 Ford Focus Stw, 1.6 tdci (109hp). 350 000km. Bought from auction.

 

Problem: check engine light is on. Code P0102 (MAF / low).

 

So far, pretty simple right?

 

WELL, so far i have checked:

 

- MAF replaced

- DPF pressure sensor changed

- MAF wiring ok (in ok values according to STAKIS VESA diagnostics)

- even tried different ECU, but as soon as i got the car running it gave the same p0102 error, and a lot of other codes.

- of course, new air filter, hoses checked, no leaks, Egr cleaned, throttle body valve cleaned, wires checked. Wire harness to ECU is open and no wires broken etc.

Contacted the previous owner and he said he has driven with the engine light on as it had no affect on the car performance. BUT, now the dpf is blocked because it has done no regens. Also now it's giving codes for egr and intake air temp. Also the car lacks power.

Turbo keeps funny noise so I assume it has something to do with exhaust back pressure.

 

Washed thd DPF but no luck there. Can't do forced regen on DPF because of the p0102. MAF trick doesn't work.

 

Does ANYONE have any ideas what to check next? I'm out of any.

 

Still, determined to get the car running again.

 

https://ibb.co/F4YPFpW

 

 

Here is some data logged from a 50km drive. DPF is glogged, but can't do forced regen because of the maf p0102 code.

 

Also EGR doesn't seem to open at all.

 

Any comments about the values? I really don't think the MAF sensor is giving those values, it takes readings from somewhere else... Also I found out that the PCV valve "rubber" was faulty, so waiting for a new part to replace.

 

PLEASE, any ideas?

no aydie

1 hour ago, abbas said:

no aydie

 

The MAF and MAP pressures look ok to me.

The Particulate Filter temperature should not be near 500c unless a Regeneration is occurring, or maybe it is getting flooded with raw fuel.

I think the Inlet Air Temperature is measured at the MAF Sensor so it should be almost the same as Ambient, but I'm not certain about that.

The EGR does not look right as you know.

The other thing that I would monitor is the Throttle Valve. On my previous car which was a later MK 2.5, Euro 5 model it was called EGR-TV. This should be near 100% except when Regeneration is occurring, when changing gear and when switching off.   

46 minutes ago, Tizer said:

The MAF and MAP pressures look ok to me.

The Particulate Filter temperature should not be near 500c unless a Regeneration is occurring, or maybe it is getting flooded with raw fuel.

I think the Inlet Air Temperature is measured at the MAF Sensor so it should be almost the same as Ambient, but I'm not certain about that.

The EGR does not look right as you know.

The other thing that I would monitor is the Throttle Valve. On my previous car which was a later MK 2.5, Euro 5 model it was called EGR-TV. This should be near 100% except when Regeneration is occurring, when changing gear and when switching off.   

Thanks for the reply. I'll do some more diagnostics.

 

IAT is on the MAF sensor.

 

The weird thing is that i'm getting 11g/s on idle with the airbox taken out from the engine. So where does that value come from?

 

 

 

5 minutes ago, Andyxxx said:

The weird thing is that i'm getting 11g/s on idle with the airbox taken out from the engine. So where does that value come from?

Maybe that is the default value that the PCM uses if there is no reading from the MAF to keep the engine running. That is Just a guess, I don't know.

Well, i measured some things and there seems to be grounding problems in the engine wire loom.

 

Cleared the grounds, but didn't help.

 

I removed the wire harness from the engine bay and it has been spliced up many times. Soldering joints etc.doesn't look very convincing.

 

I decided to check for used wire looms.

 

My loom number is 7m5t-12a690-JB

 

I already found out similar looms with matching numbers, but the last two letters do not match.

 

Does anyone know the meaning of those letters and will a different lettering (only last two) harness work on the car?