Hello All

Am having problems with my W reg 1.4 (MPI) Fabia and can't find the solution in these forums. I love the car and engine so any knowledge you can share would be appreciated!

Currently, the car idles in a jittery manner, as if misfiring slightly. Also between about 1,500 and 2,500 revs there is hesitancy, as if engine is being held back. I've not experienced the problem to this extent before.

I have tried cleaning throttle valve, replaced spark plugs, themometer was replaced last year so is working, and have recently serviced has fresh oil etc

I drive regularly 100 miles journies, so car gets a proper run quite often. It has done 160,000 miles, so I understand there will be niggles(!) but any ideas you can give would be worth a shot.

Many thanks

JR

EGR valve may need a good clean or even replaced. Also check all vacuum hoses.

EGR valve may need a good clean or even replaced. Also check all vacuum hoses.

Thanks for advice - I thought (from other posts) that MPI doesn't have EGR valve? Forgive my ignorance- what do vacuum hoses do? I have heard a "wooshing" noise on acceleration from time to time? Related do you think?

JR

When my wife's went like that, it was the MAP sensor. The MAP sits in the intake manfold, at the back of the engine. It's square-ish, with wires coming out, pointing towards the driver's side. Try disconnecting it and going for a drive. If the car's just as bad, then it's time for a new sensor. Fifty-odd quid from a dealer, or twenty-ish off eBay.

HTH

There's no EGR.

Have you had the throttle body adjusted using VCDS? This would be pretty much essential on 160k miles after cleaning it. Not sure if it will cure your issues but definitely worth doing. A code scan at the same time may also provide indicators as to what the problem might be.

Has the timing chain been changed/is it noticeably noisy?

Edited 31 July, 201015 yr by anewman

Hmm this problem is a keeper, everyone seems to have it. It's not bad with me, however the timing chain is getting noisy. Worth changin? Umming and arrin. I'm at 8700 miles. Don't know what to do either :'(

Seriously, take a look at the MAP sensor. Made my wife's into a new car, and added about 25% onto the fuel economy into the bargain. Having said this, you'll never get a completely judder-free idle with the 1.4MPi, due to the way the ECU throttles the engine to the point of stalling for emissions reasons. Stopped any hesitation when accelerating, though...

Thanks for all the responses so far. I will try the MAP sensor. I have recently cleaned throttle body and have not adjusted it. Will try that tonight using cable and see what happens.

The timing chain has not been changed and i am not planning to do so unless absolutely neccesary. How often does it need replacing?

At some point I will have to replace the poor old car i think! Has anyone gone from a 1.4 MPI to a 1.9TDI? Did you like it? I do really like the 1.4 engine - such a shame it wasn't available on newer models.

Edited 10 August, 201015 yr by jamier

Its part of the Mpi personality! Although some good suggestions made already, the idle on my baby got worse and worse untill lummox recently did the head gasket on her. TBH tho - I just got used to the judder!

The reason they dont do a newer MPI is because its the last of the "proper" skoda engines its basically a 1.3 felly engine boared out

Hmm "personality"!

Interestingly, have used vagcom to check whats going on and ignition timing at idle is varying madly between 8.3 and 4.5, while MAP remains at 418.2 and lambda at about 4 and injection on time at 4.12.

Do these figures mean anything to anyone??

thanks!

Nice one jamier I'm bumping this topic! Come on guy's anybody got any idea's?

well on mine old mpi it was so called crankshaft speed sensor, cant remember fault number now, although it showed in a vagcom. I know that on some of those cars with higher mileage it is a consequence of worn chain so timing is slightly off. Timing chain kit comes really cheap on ebay dough. Does rhe car come up with any error codes?

Hmm "personality"!

Interestingly, have used vagcom to check whats going on and ignition timing at idle is varying madly between 8.3 and 4.5, while MAP remains at 418.2 and lambda at about 4 and injection on time at 4.12.

Do these figures mean anything to anyone??

thanks!

Hi!

did you found what was the problem with your car?

I have a 1.4 MPI Octavia and I have exactly the same problem. After reading with VAG, the Ignition is oscillating from 3 to 8, and the idle osscilates from 500 RPM to 800 - 1000 RPM.

But, after driving with a higher RPM and the engines heats, the Idle will be steady.

Looks like this happens only in some engine operation mode.

Relu

I'd probably go with either MAP, camshaft position sensor or timing chain. The camshaft position sensor would retard the timing - as would the timing chain - the map could be at fault...

...Of course it could also be the pre-cat lambda stuck on a high signal possibly.