2009 Fiesta MK7 1.6 Tdci really weird intermittent issue..

[ayvo]

So as some of you may know, basically a month ago I got my fiesta (1.6 tdci), and in my month of ownership its only done this issue twice, once being 2 weeks ago and the 2nd being today, however this time it was severely worse, I was just wondering if anyone's had a similar issue or heard of it or know what could be up.. Basically what happens is that the engine light flashes on and off (the one with the exclamation mark only not the normal one) and sometimes the airbag light does too, and while this happens, the speedometer drops to 0 mph and the engine judders and feels like as if its about to cut out, sometimes it even does it without either of the lights coming on, it does it quite often and seemed to happen a lot more with the accelerator pedal further down (although I'm not sure if this was a coincidence).. like I said its very intermittent and it's only happened on 2 journeys in my 1 month of ownership, all help and questions are appreciated and welcome, thank you

[ayvo]

Seemed to do it constantly too this morning during the school run, same thing happened about 8 or 9 times just minus the engine light and abs light this time.. anyone got anything? 

[TomsFocus]

Have you got the Forscan cable yet?

[unofix]

FORScan: https://forscan.org/download.html

 

Type 1 cable - ELM327(modified) :- https://tunnelrat-electronics.fwscart.com/USB_Modified_with_switch_ELM327/p4541936_17045457.aspx

OR

Type 2 cable - vLinker FS :- https://www.amazon.co.uk/Vgate-vLinker-Adapter-FORScan-MS-CAN/dp/B0952P4MLP/ref=asc_df_B0952P4MLP/?tag=googshopuk-21&linkCode=df0&hvadid=534732308385&hvpos=&hvnetw=g&hvrand=491027302792504503&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006688&hvtargid=pla-1430824679036&psc=1

[ayvo]

https://www.ebay.co.uk/itm/394228928129?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=k0p0wdnzs3w&sssrc=2349624&ssuid=0y0MDcFSS3S&var=&widget_ver=artemis&media=COPY

I ordered this one since the other one had some really long delivery times, this one should be here within 3 days, the thing is that since clearing the codes the car seems to have been fine, so I'll get it scanned using the forscan once it decides to do it again and I'll update you guys

[YBTURBO]

sounds like the symptoms i had when an injector was failing, in my case it turned out to be a leak in the head gasket soaking the injector in coolant but it could be a almost dead injector, blocked injector, bad wire, air getting in the lines. like the rest have said no1 thing to do is get forscan and an adapter and see what it shows up.

Dont go down the long route i went down of reading too much into it and taking all sorts apart BEFORE getting forscan, all it did was cost me a crap load of time to get nothing done. After getting forscan it showed up a code telling me there was a problem with cylinder 3 and from there i pull that injector and noticed the problem.

Good Luck and keep us posted 🙂

[ayvo]

6 hours ago, YBTURBO said:

sounds like the symptoms i had when an injector was failing, in my case it turned out to be a leak in the head gasket soaking the injector in coolant but it could be a almost dead injector, blocked injector, bad wire, air getting in the lines. like the rest have said no1 thing to do is get forscan and an adapter and see what it shows up.

Dont go down the long route i went down of reading too much into it and taking all sorts apart BEFORE getting forscan, all it did was cost me a crap load of time to get nothing done. After getting forscan it showed up a code telling me there was a problem with cylinder 3 and from there i pull that injector and noticed the problem.

Good Luck and keep us posted 🙂

did your symptoms include the mph dropping to 0mph and engine light flashing on and off a few times like mine?

[YBTURBO]

4 hours ago, ayvo said:

did your symptoms include the mph dropping to 0mph and engine light flashing on and off a few times like mine?

didnt have the MPH drop but mine is also slightly older and a 1.4tdci, but the cog with the ! in the center of it and the random shudder/judder. when i first noticed it, it would only happen once or twice a week maybe then over the next 2 months it got more and more often until the car eventually put itself in limp mode and the cog and ! never went back out. that was when i wasted a whole lot of my time taking things off cleaning them and putting them back before getting forscan that told me it was cylinder 3 issue. and like i say on mine it was a leak on the gasket but there's a whole host of things it could be. Forscan is deffo the place to start if the light is coming on and then going off it should at least have saved a pending code and forscan will tell you what that is  🙂

 

[TomsFocus]

The speedo dropping is caused by losing the ABS speed signal, the engine struggles to work out the precise fuelling because of that and just defaults to a richer mixture which will keep the engine running, but not as well.

It's going to be a wiring fault somewhere.  And given the airbag warning as well, I'd suggest it's probably a fault at the clocks end.  But it could be also be around the GEM, PCM or ABS pump.  We really need some codes for this one...

[ayvo]

Yeah, like I said the codes were cleared since the car wouldn't go back to normal without clearing the codes, once I get the forscan I'll be sure to get it on as soon as the problem happens again if ever 

[ayvo]

I'll keep you guys updated 🙂

[ayvo]

So it happened again.. First time since September 25th which proves how intermittent this fault really is, however this time it was considerably worse, and strangely as soon as the codes are cleared the car starts behaving perfectly normal.. what happened this time is that the speedo kept still dropping to 0 and the engine was juddering (got this bit on video https://youtube.com/shorts/Ex1kYsFV95c?feature=share) as well as all the engine light flashing on and off here and there, but the weird thing that happened this time is that while driving every single warning light came up on the dash, the mileage was just showing dashes (see picture, car was started at this point) and the throttle stopped doing anything at all, and once I pulled over and came to a stop and decided to try restart the car, at this point the car turned off (but the speedo and all the warning lights stayed on) the keyless start button decided to just not react at all, and nothing in the entire car wanted to do anything, till eventually after a few mins of leaving it, it decided to go back to the same issue as before (speedo dropping to 0 and engine light but still drivable).. I got the car hooked up to my forscan and these are the codes I managed to get from it (picture, most of them seemed to be "no communication with... module etc).. all help and questions are welcome, and like I said since clearing the codes the car has gone back to being perfectly normal, as it does every time for a couple of months.. 

 

[unofix]

Well I have to say that is the most "U" codes I've ever seen in one list !!!

So it comes down to the fact that communication on the Canbus is somewhat buggered up.

The common causes of this are usually:

Faulty instrument cluster. Poor solder joints breaking up and causing high resistance, this been the result of the lead free solder that was used at the time when the IC was manufactured.

OR

There is water getting in to the Body Control Module (BCM) which is part of the passenger compartment fusebox assembly.

Your car is about the right age for both of the problems, but it normally affects the Focus more than the Fiesta.

The test for a faulty IC is to thump the top of the dashboard above the instrument cluster when the fault is present. If it changes then you are probably looking at getting it repaired/refurbished.

The BCM has to be disconnected and the connectors and pins checked for signs of water ingress. Look for greenish corrosion inside the plugs.

If neither of them seem to be the problem then you are probably looking at a faulty connector with a loose pin or damaged wire which is on the canbus circuit.