Hi,

My Fabia recently started jerking while accelerating in every gear at all speeds.

Its a 2002 1.4 MPi 8v.

I have changed the oil, antifreeze, fuel filter, oil filter, coil pack, spark plugs, air filter and Temp sensor with no luck still!!

Now when I reach about 60mph the car seems to go into 'limp mode' and loses power and the Engine management light comes on for a while.

I have ordered new injectors and rail and hoping this helps but does anyone have any other suggestions?

Could it be the MAP sensor?

Thanks.

Dan.

Edited 23 November, 201411 yr by Ackadappa

Get it scanned with VCDS, that'll tell you the issue

I'd try a compression test.  Cylinder-to-cylinder leak in HG?

I had it scanned about 10 days ago with the only fault coming up as battery/alternator. Which is because the alternator is weak is think.

Ok ill give that a go. Getting desperate as i need the car for work :(

Test the old injectors before replacing them. They might still be usable. I have the 1.4 mpi 8v engine and after I had them cleaned, it was definitely running better. I've also replaced my catalyst. The last one fixed all of my problems. I wasn't passing the emissions test and getting errors from the 2nd lambda probe after the catalyst, saying the fuel mix was too rich. I didn't install a genuine Fabia catalyst, since a new one was about 250 euro, I found a Golf MK5 1.6 litre one and it went just fine. Now, with the car in neutral, when I press the accelerator pedal, it revs much faster as before. Yes, it is a bit akward for a petrol engine to have this kind of problems, but in my case, I belive I've damaged the cat because I'm mostly driving in the city at rush hours, mostly 1st and 2nd gears and a lot of idling. These engines are OHV, not meant to go high revs, but after one year of driving one, I've found that keeping them over 2200-2500rpm it's the best way to drive. The cat is clean, lambda probes are running fine and the mpg increased since I've decided to change gears over 2500rpm. The EML goes on if there is a fault in the exhaust system, starting with the exhaust manifold, oxygen probes, catalyst and so on. If you have a hole in your exhaust the sensors might sense it and change the fuel mixture according to the oxygen level from it. Run a full scan with a VAG-COM interface and post it here, I'm pretty curious about what is says. If you have the possibility, run an emissions test. In best case scenarios, this is how it should look like.

Dan2707 on here has an injector cleaning rig

Hopefully getting it fully scanned soon so i will post the results.

Thanks for the advice.

I will look into it and keep you updated.

Just had it scanned.

Got code P0303 so cylinder 3 is misfiring. Maybe injector problem.

Also got code P0118. (Temp sensor high input)

The temp sensor was changed 2 days ago so not sure why thats coming up.

Run a full scan with a VAG-COM interface and post it here, I'm pretty curious about what is says.

As above.

 'Got code P0303 so cylinder 3 is misfiring. Maybe injector problem.' - check the spark plugs and the wires. It's cheaper to start with the basics.

'Got code P0303 so cylinder 3 is misfiring. Maybe injector problem.' - check the spark plugs and the wires. It's cheaper to start with the basics.

I already replaced spark plugs when I bought the car.

And the coil pack sits straight onto them so there isn't any HT leads.

Might be a long shot as i dont know your engine specifically, but is there a maf sensor between airbox and intake manifold?

My fiesta used to do this and it used to be when the wire in the maf got clogged up and therefor the ecu wasnt getting an accurate air reading.

on the other hand cant see this causing a problem just on cylinder 3, if you think it could be injectors always try some redex first, double dose in your petrol tank should clear any blockage.

Im sure i read that the MPi doesn't use a MAF sensor. I have used redex to no avail.

Running out of ideas other than changing the injectors now :/

Cheers

Do you have CO and Lambda values? A misfire caused by fuelling is pretty certain to give you a bad Lambda and high CO, although it's less certain to throw an error on VCDS (if it does, it will probably be an "implausible value description").

 

Low system voltage can throw errors with all sorts of systems, including ABS, traction control (if you have it), PAS (Furbies have electric power steering, which needs good alternator power to work right) so it's not unreasonable to think that it could cause EMS errors as well. So I'd check the alternator output under load.

I think the car has a weak alternator as the light stays on for a while until i start driving it.

So i will get that checked and i will get some values for the 02 and lambda sensors.

Thanks.

Im sure i read that the MPi doesn't use a MAF sensor.

 

That's right, they only have a MAP sensor on the inlet manifold.

 

Could the MAP sensor cause these problems?

Have you tried swapping the coil packs to see if the fault moves cylinders.  Can;t always guarantee a new coil pack will be top notch, same with the spark plug, swap 3 with 1 and see what happens, if the warning moves then you have your culprit, if not check the gaps, rare for gaps to be fecked but again have see a badly supplied plug thats been damaged in transit etc.

 

Also another thing to check, but you would usually have really bad running, the o rings on injectors can become crappy or may have even fallen off when they have been removed etc.  So check they are all present and correct.  I lost two in a previous engine ( they burn off)   Again if nothing on the spark side swap the injector to see if it too moves.

 

Pain but at east theres not much to move around like on some cars

 

I'd also look at battery after this, a shagged alternator will smash your battery too, so get a proper test done on both.

 

unfortunately it's always a simple thing, but it's locating it the quickest way which is the hard trick to get right

Yeah its becoming very annoying..

Ill try what you have suggested and keep you updated on here.

Thanks.

Have you tried swapping the coil packs to see if the fault moves cylinders. 

 

I don't think you can do that on the MPI. The coil pack is a single, sealed unit which clips directly onto the spark plugs without HT leads.

I think the car has a weak alternator as the light stays on for a while until i start driving it.

So i will get that checked and i will get some values for the 02 and lambda sensors.

Thanks.

The "charge light" is a sort of binary version of a voltmeter, and lights up when the voltage output is under 12v. My Dad had similar symptoms to those on the light which ended in a dead alternator, so I'd get a trustworthy garage or auto electirian to look at that soonest. Odds on they'll not charge for the diagnostics as long as they get the job if the unit needs replacing.

Getting it looked at at the weekend so will get that checked first.. thanks

Edited 26 November, 201411 yr by Ackadappa

I have replaced the injectors but have hit a problem...

The part numbers are identical but the injector loom/connector is a different shape. The old ones were more squared whereas the new one are rounded so i cannot connect them up.

P.s ... the old injectors were pretty filthy so im hoping that was the problem..

Any help is appreciated!!

Get the old injectors cleaned ultrasonically. It's a lot more aggro and expense to replace the injector wiring loom to make the new ones work.

 

These people can do it locally:

 

Company BEDFORD BATTERY CO LTD Address 1-3 WELLINGTON STREET
BEDFORD
MK40 2HZ Contact MICK, PAT, KEVIN Tel 01234 340661

Edited 29 November, 201411 yr by sepulchrave