1.4 mpi low performance

[110ivan]

My Fab 1.4 (8 valve Skud engine) is driving me mad.At anything below 3000 rpm,the engine is sluggish in any gear,I can't drive the bloody thing slowly in 3rd or 4 th gear and when I engage fifth the power instantly dies,it feels like pulling on fifth gear.Even when I was driving on the autostrada in sicily last week at around 140 kmh in forth gear,I put it into fifth and the engine will take a long time to build up the revs and gain speed again,A friend of mine in a 1.2 Fabia was simply flying by past me.The engine is constantly hunting at anything between 800 and 950 rpm on idle speed and the car really struggles at a slight incline,again in first gear,wheels started to spin with traction control on,as I had to rev the bloody thing,nearly burnt the clutch,when the friend of mine again in his 1.2 fabia,without traction control,went up nice and easy and even engaged second gear in process......The fabia's only got past 50,000 kms last week,dealer connected the computer but no faults appeared...Car's got a heavy rattly timing chain....could this be the cause,maybe the timing's out....Any ideas please as I'm desperate ?.

[ultra_joel88]

throttle body?

[ap0gee1978]

Dodgy coolant temp sensor can cause lumpy idle as well, and won't necessarily throw up a fault code (see my guide, here - soon to be supplemented by a thermostat body replacement guide :thumbdwn: ) but in this case, I'd give the throttle body a good clean in case the butterfly valve is sticking. As long as you don't remove it, it won't need resetting. Just be careful not to clean it with anything that can shed lint, otherwise it's next stop: inlet manifold! :eek:

HTH

[snownrock]

SWMBO's car does exactly the same, bought the temp sensor and housing, still havent had chance to fit it though because of the weather and lack of a garage/driveway. So hopefully that will fix it, going to replace the coolant when it gets serviced in a couple of weeks to (aswell as a full healthcheck) so hopefully all will be well.

@ Apogee, i can get to the throttle body right (just take the breather pipe off at the back of the block?), but what would you recommend to clean it, would WD40 be ok or wrong? im a complete beginner spanner monkey.

[ap0gee1978]

@ Apogee, i can get to the throttle body right (just take the breather pipe off at the back of the block?), but what would you recommend to clean it, would WD40 be ok or wrong? im a complete beginner spanner monkey.

Yeah - it's under the black slug thing at the top of this pic (as ever, ignore the yellow oval!)

ISTR one of the securing nuts is a little fiddly to get at, but nothing a socket extension won't solve. I think the 'recommended' cleaner is carburettor cleaner, however I used white spirit, I think. Meths would probably do also. As WD40 leaves a residue, however, I'd be inclined to use something else - you want any drips or smears to evaporate otherwise you won't really be doing any good...

[snownrock]

Grand, thats what i thought it was, now if it would ever stop raining i can have a go at fixing the damn thing. I shall nip to halfrauds then and buy something appropriate if it looks like it needs cleaning.

[110ivan]

I have a can of Wurth's carburettor and throttle body cleaner ?.Should I use it with the engine running or switched off ?.

[ap0gee1978]

I have a can of Wurth's carburettor and throttle body cleaner ?.Should I use it with the engine running or switched off ?.

I did it with the engine off, since you need to open and close the butterfly manually, which would have, er, interesting consequences if it was running. AIUI, you would have the engine running if you were cleaning a carburettor, but obviously you're not. Doesn't the label tell you how to do it?

[110ivan]

What about the rattling timing chain ?.Does it effect timing,engine is running like a bag of nails.

[ap0gee1978]

AIUI, a worn chain just makes a racket. That's the advantage of a chain over a belt - it can't slip as the teeth on the sprockets locate positively in the links of the chain. Because the engine is pushrod rather than overhead cam, I believe the consequences of a snapped chain would be less severe than a snapped belt too, however I don't think your car's got to that stage yet!

Mind you, if the chain was that loose, then there'd be a bit of play that might affect the timing, I suppose. There was a DIY guide for the Felly (same process on the Fabia), but I'm afraid I've no idea where it is now...

[snownrock]

Think im just going to replace the temp sensor tonight regardless of weather as it wont take long, see if that makes a difference, then do the thermometer housing when its serviced.