So my Skoda has been misfiring since being sat around for a couple of months.

Checked sparks, little sooty but OK

Checked injectors. All 4 worked (swamped the order)

Unclipped the fuel rail one at a time, found that 2 worked and 2 didn't.

2 on the far left worked, 2 OK the right didn't.

We got a multimeter and tested each one.

We got readings of roughly (left to right)

8v, 6v,3v, 2v.

We assumed there is an electrical fault, my friend thinks there may be an issue with grounding.

Can you please let us know where all the grounding points are so we can clean them up/replace.

Any further suggestions?

Cheers

What engine are you talking about, the fuel rail is just a tube, it isn't electrical.

What engine are you talking about, the fuel rail is just a tube, it isn't electrical.

I have the 1.4 2002 Fabia.

It looks like this. I'll take a picture when I get home, this is just online.

http://ebayapi.loc8apartltd.netdna-cdn.com/00/s/MTA2NlgxNjAw/z/QVIAAOSwPc9WuE9Q/$_1.JPG

We tested the plugs that go from the top of the fuel rail, to the injectors to open them and allow the fuel to inject in

Ok, that's the wiring loom attached to the fuel rail, replace the loom if it's failed.

 

I'd check the coil packs as well if the problem persists, I assume the engine is a BBZ.

I replaced the coil pack last year as it failed on me then. So that should be fine.

I'll try find a loom.

Any chance you know where it would earth to? We want to try clean that cable up too

I replaced the coil pack last year as it failed on me then. So that should be fine.

I'll try find a loom.

Any chance you know where it would earth to? We want to try clean that cable up too

 

Do you only have one coil pack or four separate pencil packs?

Fuel injectors all have a constant 12V connection on one pin, and are energised by the ECU connecting the other pin to ground in a PWM manner. So no full-time ground connection.

They ground through the ECU to the main ECU ground as Wino says. It seems the loom may be at fault.

They ground through the ECU to the main ECU ground as Wino says. It seems the loom may be at fault.

 

I have just one coil pack.

 

We will give the ECU ground a clean up, try that first, I have managed to only find one loom online which is second hand from a breaker, it comes as the whole rail for £25, any chance you guys can find it elsewhere? I've looked but I;m not really knowledgeable about the name and how to search for it

One coil pack means AUB, and that means HT leads, did you replace the HT leads at the same time as the coil pack? If not you may need to replace the whole lot all over again.

 

I thought you said the injectors were working.

http://www.eurocarparts.com/ecp/c/Skoda_Fabia_1.4_2002/p/car-parts/ignition/car-electrics-and-car-lighting/ignition-coils/?413440381&1&deee84706462e4ff5aba031469240adbe71c0ee5&000197

That's the coil pack we put in, I don't think we need ht leads?? Please let me knoeif I did.

The injectors work, but I think the two on the far right don't have enough power to open up. We switched the two on the far right with those on the left, and the problem stayed on the far right side. So the injectors aren't faulty

http://www.eurocarparts.com/ecp/c/Skoda_Fabia_1.4_2002/p/car-parts/ignition/car-electrics-and-car-lighting/ignition-coils/?413440381&1&deee84706462e4ff5aba031469240adbe71c0ee5&000197

That's the coil pack we put in, I don't think we need ht leads?? Please let me knoeif I did.

 

 

No, there are no HT leads on engines with that coil pack. You obviously have the 8 valve MPI engine.

Edited 19 May, 201610 yr by TMB

I give up, I cannot torture people into divulging which engine variant they have so this was all guesswork. Live and learn.

 

Finally after 12 posts we now know it's a 1.4 MPI, take it away guys.