Hi Guys,

 

So after an eventful week. Despite running perfectly fine the Fabia has decided that it still wants to play funny buggers and that I believe it wants a new injector on cylinder 3. Every so often when we stop at the lights or are stationary the EML will start to flash soon as we knock it over 2000rpm it goes out and every so often it will start to misfire. Turn the car off and then back on after a few seconds and we are off and away right as rain. 

 

If it could be anything other than a dodgy injector I am open to suggestions. Bare in mind that I have replaced all the ignition coils and spark plugs already at this point and run injector cleaner through the system.

 

So does anyone have any experience removing and replacing an injector on this engine type (BMD) as much as the misses is dying to get a MKII Monte Carlo we cant afford it whilst I'm at uni lol.

Remind me, have you done a compression test yet?

Yes I should have put that lol. One of my friends who actually runs his own garage came round and did it for me the on Saturday. Compression is good across all three cylinders. I couldn’t tell you what the readings were I just left him to it 

Oh, that's good news.

I think injector removal/replacement is fairly straightforward, though I've not done it, to date.

A screw or two to free the fuel rail, a clip to release the injector from the rail, a wiring connector to undo, then a bit of pulling.

May need a new o-ring or two when fitting replacement.

Rag to catch spilt fuel; no smoking!

That seems way to straight forward! Is there no pressure to release from the fuel system first? 

 

If if it is that straight forwards I just need to find myself an injector then lol 

23 minutes ago, mikey362 said:

Is there no pressure to release from the fuel system first

 

Oh yeah, Schrader valve under a grey plastic cap at the nearside end of the rail.

Injector part number looks like 03D 906 031 C, from here: https://skoda.7zap.com/en/cz/fabia/fab/2005-453/1/133-133040/#6

Looking at that, it seems like it's maybe easier to leave all three injectors clipped into the rail, then pull all three out with the rail, then undo clip (item 5) of the one you want to replace.

 

Or maybe take all three of the clips off, and pull the rail off all three injectors?  Let us know what's easiest?

Edited 2 May, 20197 yr by Wino

Thanks wino, and yeah I’ve looked at the diagram and that’s the right part number to.

 

I'm thinking of having a trip to my local scrappy to see if I can get an entire rail with injectors. Make sure they all work and clean them out. Then just swap the entire fuel rail. Probably much quicker when actually under the bonnet lol.

When you say clean them out, what is your plan for doing this, I don't think that you can try tricks like forcing them open and reverse cleaning with a suitable fluid.  How much would it cost to get all 3 checked/serviced at a fuel injection place? Doing that would allow your car to stay on the road and then get properly checked injectors fitted when convenient, there will be no history with scrappy supplied injectors - just my thoughts as getting the same results from your engine after stuffing used injector(s) on that car might then send you off in the wrong direction.

 

Edit:- if a new injector does nothing it might be a control wiring issue.

Edited 2 May, 20197 yr by rum4mo

@rum4mo Your not far off my plan to be fair.

 

If I can get the entire rail I was planning on getting the 3 injectors from the scrappy cleaned out and check they work. I’ve seen the videos on YouTube about cleaning the injectors and I’m not equipped with the time or equipment for doing it so I was planning on passing them on to my mate who can get them sorted for me where he works.

 

The car isn’t about to die so I’m not in a dramatic rush to get them done unless the car really starts to Chuck it’s dummy out.

 

Its that or if I can’t be bothered to go to the scrappy I find a refurbished one as I know it’s cylinder 3 that’s the issue.

Move the one from cylinder 3 to another cylinder, and check that the fault moves with it, before spending any money?

That’s a good call actually Incase it’s the wiring 

...which is more likely than injector failure.

If it is the wiring, what’s the solution? New injector loom? 

9 minutes ago, mikey362 said:

If it is the wiring, what’s the solution? New injector loom? 

 

Repair the existing loom by chopping out the dodgy wire and splicing in a new length.

 

Is this a trick question?

9 hours ago, sepulchrave said:

Is this a trick question?

 

Haha no it’s not, I’m used to working on classic minis and that was over a decade ago so if it’s advisable to get a new loom then that’s what I’d rather do.

I would personally just hunt down any wire breaks and repair them. Engine loom is all one chunk, I think, so a bit 'baby out with bathwater' to change whole thing out for one bust wire. All the 12V feeds are easily checked, I think, and the low side wires will run straight to engine ECU pins. Can tell you pin numbering if required.

 

Okay I wasn’t sure if there would be separate parts of the loom that could easily be replaced or not.

 

On the minis we would have just found the wire with a break in it stripped it out and replaced it. It’s not that easy on newer cars lol.

 

planning on swapping the injectors on cylinders 2 and 3 this weekend and then checking the daily codes weather permitting so should have an answer as to what it is soon hopefully

Edited 3 May, 20197 yr by mikey362

Hi guys,

 

sorry for bringing this thread back up but I’m scratching my head and can’t figure out what my next move should be.

 

A couple of weeks ago I swapped the injectors round and it seemed to solve the issue as far as we could tell. As this misfire is intermittent as in, it doesn’t happen every time the car is used. Also if the EML does come on it disappears if you switch the car off then back on and there is no fault code.

 

Anyway it’s been a couple of weeks and I’ve done some mixed driving country roads, motorways and the usual nursery runs and nothing. I went to pick up some new alloys last night and it happened again.

 

Im left with two thoughts is the fuel filter knackered and just letting crap through from the tank, I honestly dont know if it’s ever been replaced . Or could it be that we’ve been using Asda fuel for too long and it’s having a bad effect?

 

as a recap we have

replaced all coil packs

replaced all spark plugs

compression test is good on all cylinders

injectors all seem to be fine

 

I have read about burnt valves but I’d expect the car to misfire pretty much all the time especially once warm which it does not.

 

Any input would be great 😊

Fuel filter will not be the issue, it sounds like you have an intermittent electrical fault in the wiring loom, these are really hard to pin down even for a good auto electrician.

 

I really don't have anything else to add and we're going round in circles now, you need to find and fix the intermittent continuity fault.

19 minutes ago, mikey362 said:

and there is no fault code

What are you using to read this?

 

 

 

I don’t know what it is to be honest @Wino it’s been done through the obd and the laptop at my mates work I’ve no idea what the software is. I thought it was weird when nothing showed up as the car must have thought something was wrong to show the EML but literally nothing not s single code.

 

Anyone know how hard it is to change the loom on a BMD think it might just be easier than hunting down the break.

It's probably VCDS then.

Weirdly, I scanned a friend's Fabia recently with an emissions light on and didn't see any codes via a full autoscan, but got a relevant code when I scanned the engine module separately, so that might be something for your mate to try next time you're passing his place.  

I would suggest another compression test too, with numbers written down for you this time.

 

Virtually no-one on here will have changed a loom on one of these engines, with the possible exception of @Tech1e.  I can't imagine it's that tricky except for access to some of the connectors, like knock and crank sensors which hide away behind the engine, under the inlet manifold.   But unless you buy new for biiiig bucks, any secondhand loom you fit may also have problems, including busted connector latches done during removal.  

Edited 29 May, 20197 yr by Wino

Thanks @Wino I’ll try and swing round to his place in a few days and see if he will check the module and do me another compression test. I’ll see if I can find my volt meter out to do the continuity test on the injector wiring.

 

The loom looks pretty simple I might just inquire about the cost of a new one if I can’t find the break. I mean it’s not the end of the world it’s just annoying the car runs fine otherwise and doesn’t lack any power for what it has anyway.

6 minutes ago, mikey362 said:

I might just inquire about the cost of a new one

 

Sit down before you get the answer.

Randomly picking one of the four possible part numbers for a 2006 BMD shown here, and putting it into a parts site I often use to get an idea of dealership prices, I see this page:

https://www.allcarpartsfast.co.uk/vw-audi-seat-skoda/vw-audi-seat-skoda-03d971595at-harness/