Hi All,

I have a bit of a problem with my 2005 Mk2 1.6 tdci Focus. It has no DPF, so any problems with that can be discounted.

The problems began last winter, when the car would occasionally start up in limp mode on cold mornings. Normally, this was solved by shutting off the ignition, then starting it up again. This issue gradually got worse and the shut down start up again trick worked less often. I bought a cheap OBDII reader off ebay, which pulled off the faults -

P0047 - Turbocharger/Supercharger Boost Control 'A' Circuit Low

P0102 - Mass or Volume Air Flow 'A' Circuit Low

P0100 - Mass or Volume Air Flow 'A' Circuit

So, as the Turbo works absolutely fine when it's not in limp mode, I bought an after marker Mass Air Flow Sensor and fitted it. This didn't solve the problem, so I took it off and sent it back.

Then, about two weeks ago it started stalling at low RPM. It wouldn't start straight away, only after a minute of being switched off. So I took it into a garage to have a diagnostics done on it, which gave the faults -

P0483 - Fan Performance Part 1

P135B - Glow Plugs

P1632 - Smart Alternator Faults Sensor/Circuit Malfunction

P0102 - Mass or Volume Air Flow 'A' Circuit Low

P0047 - Turbocharger/Supercharger Boost Control 'A' Circuit Low

P1180 - Fuel Delivery System Malfunction Low

P0089 - Fuel Pressure Regulator 1 Performance

P0193 - Fuel Rail Pressure Sensor Circuit High Input

U0073 - Control Module Communication Bus A Off

The garage then cleared it and took it for a test run. They said the the fuel faults reappeared along this the MAF (which I informed them I had tried replacing and didn't work). They suggested I might be having problems with the fuel pump, but as it was working, ok at the time, they sent me home with it. The next day I was driving at 70mph in 3rd gear, so most definitely not low RPM and it cut out on me again. At first, I lost all throttle response and as I coasted to a halt, it then stalled. So I called the garage and got it booked in again. I did a bit of exploratory driving later that day, and discovered it was only stalling on a cold engine, so I let the garage know this when I took it in. I also noticed that when left to idle, the rev counter would fluctuate, dipping, then rising, gradually worsening until it stalled.

The garage has another look at it, drove it on a cold engine (which cut out on them) and cleared the fault codes again. They tried unplugging the MAF sensor, which they said must be at fault since the car worked better (no stalling) without it plugged in. Since I could get a replacement cheaper than them (OEM from Ford this time!) and was easy to DIY, I picked the car up to fix at home myself. Which brings me to this evening.

I drove around for a short while (long enough for the engine to warm up), stopped to get chips and left for home again (the MAF was still unplugged at this point). On my way home the car cut out on me twice. I took it for another spin a bit later, when the engine had cooled down and with the MAF plugged back in. It cut out. I unplugged the MAF, it cut out. I got the engine warmed back up and plugged the MAF back in, and it cut out. I finally unplugged the MAF on a warm engine and it still cut out.

So, I'm left with a lot of questions. If the MAF being unplugged no longer makes a difference, is it not at fault? Which fault could it actually be? Could it be all of them? Could it be something unrelated like the ECU itself or maybe a broken cable?

I just don't know where to go from here, the car is pretty much undrivable. Any insight would be very much appreciated.

* EDIT - Here is a video of the idling fluctuations.

Is the oil level spot on if too much the engine can cause erratic idling, as for it cutting out my missus car TDCI kept cutting out this was caused by a blocked fuel filter was ok on light throttle but anything harder it would cut out and throw up all sorts of weird codes.

I see you have P1632 there is a known fault with the loom from the back of the alternator(I will try and find it) maybe this is a factor ?

just a couple of ideas

I'm not a car technician but the fluctuations in revs could be caused by the engine anti-stall, .e.g. notice how the revs dip and then suddenly shoot back up again as if the engine has detected a near stall situation and has fuelled to compensate.

And those list of faults is quite lengthy :(

try a fuel filter change buddy- had similar symptoms on my focus tdci :p

I think your looking at a corroded wiring issue here.

You have an issue with the fire triangle, fuel, air, and spark, I dont think they are seperate issues...

I would say either get it to a reputable or knowledgable auto electrician, or to Fords for a proper (even if it is more expensive) diagnostics. But the fact that all three are having issues, would indicate a potential wiring issue.

It could be that the turbo is misbehaving, the MAF is misreading and so the fuel management is shot, but as you swapped the MAF, you have removed the chance that it is the fault (although it would be better to have tried a genuine).

I see Mass Air Flow figures somewhere in the problem.. Have you done the obvious stuff like check theres no dead pigeon in the air intake. Maybe disconnect the air intake from filter housing and trial that?

Sent from my GT-N7100 using Ford OC mobile app

Hey All, Thanks for all your replies. I did a fuel filter change earlier, and it seems that it may be mostly cured. When I took it for a test drive straight after it started in limp mode, however after stopping and starting again it seems to be absolutely fine (maybe limp mode was caused by me taking the battery out?). I'll let you know if any problems re-occur, and maybe start checking of some of the other things you guys have suggested.

Thanks Again!

Allen

you really need to reset the error codes, as if they are all coming as a result of this issue you need to see if its still happening, I thought these codes had all come together as a result of the error....

I would definatey keep an eye on it though

+1 clear the codes