While away from home my Skoda, Fabia Mark II 3 cylinder engine had what was diagnosed as a collapsed cat, very noisy exhaust, virtually no power.
 

This was replaced and the car sounded fine.

 

 The garage that replaced the cat said the engine management system showed a fault on the cam sensor, this was replaced before driving the car.

 

I returned home however, the engine fault didn’t clear and the car drove normally at slow speeds, but not at higher speeds or up steep inclines.

 

I use the car for half a day around town parked up, returned to it. Tried to start it and it wouldn’t start.
 

The engine turned but it seemed as though the cylinders were not firing correctly or insufficient petrol was getting to the engine.

 
I tried to read the management codes with an OBDII reader (Topdon Artilink 400, however, it returns a fault saying unable to download information.

 

The only thing I did differently on returning home, shortly before the car failed was to park facing uphill on our steep road!

 

Any suggestions?

 

Anyone near me who can do a full diagnostic reading? 

Did you leave it in a forward gear on this steep hill? 

Yes I did!

Is it a single cam 60 horsepower 3-cylinder or twin cam 70bhp?

Make: Skoda

Model: Fabia 2 Htp 70

Colour: Maroon

Vehicle Type: Car

Body Style: Hatchback

Fuel Type: Petrol

Engine Size: 1198 cc

BHP: 68 BHP

 

Thanks!

I would suggest that you, or someone on your behalf, checks the cam timing. 

There are two removable covers at the gearbox end of the camshafts.

When removed, these give visibility of some slot features on the ends of the camshafts.  They should be parallel to one another, and when cylinder no.1 is at TDC, parallel to the head/block joint. 

Any departure from this indicates that the timing chain has jumped.

Thanks for your advice - I wasn't aware that could happen...!

 

I got a mobile mechanic on the way to take a look and will pass that on to them.

 

I think i need a full diagnostice readout given recent issues with CAT and sensor...

Hi again breezy pete - just found a previous post where you explain further:

 

 

Diagnostic readout will not be as useful as a visual check in this case.

I've just had the cam shaft covers off and the cam marks seemed aligned to my eye

 

I'm wondering if its possible there was an underlying fault (with sensors / ECU / management system) that might have led to the failure of the CAT which was undiagnosed and now CAT has been replaced its still there / failed?

5 minutes ago, Drewphotoboy said:

I've just had the cam shaft covers off and the cam marks seemed aligned to my eye

 

Good start, but you would also ideally take spark plugs out, rotate engine in running direction until no.1 piston is as high as it can go, then check slots in cams are also now parallel to headgasket, to rule out a a chain jump just on the crankshaft sprocket. 

Edited 15 July, 20232 yr by Breezy_Pete
F in autocorrect

Thanks Pete but I'm afraid that I'm not able to do that at present....

If timing chain had jumped would I not have been aware of it when it happened? Strange noise or some indication?

May have happened as you started to crank it over after the hill park-up.

Unfortunately the design of the chain tensioner is such that if the engine is rotated backwards, oil can be squeezed out of it, meaning there isn't enough push on the chain guide to ensure that the chain stays engaged on the sprockets.

Ah - i see your reasoning - although I usually park downhill I have parked uphill many times before.

2 hours ago, Breezy_Pete said:

Did you leave it in a forward gear on this steep hill? 

 

When I read that I thought "Oh Merde!"

 

Sadly I think that Pete is probably correct in this instance as much as we all hope he isnt.

22 minutes ago, Drewphotoboy said:

Ah - i see your reasoning - although I usually park downhill I have parked uphill many times before.

 

Drum rear brakes?

And I imagine that running/turning over the engine is not a good idea??

7 minutes ago, J.R. said:

Drum rear brakes?

Yes!

Just to put things in order...

 

• CAT was replaced on Wednesday
• I was told the engine diagnosis showed a fualty cam sensor - this was replaced - the light was not reset and didn't go out.
• I drove 100 miles without issue but the car was a little sluggish at speed and uphill.
• Felt like it needed tuning.
• Got home and next day did a few short trips around town - no issue.
• Parked up outside house facing uphill.
• Next morning car turned over and caught but very uneven and wouldn't run
• Spluttered, coughed as though misfiring or no petrol.
• Now it doesn't catch at all.

Do this fit your thining re timing chain jump??

Might it be something to do with petrol supply...?

or the fact the person who fitted the new cam sensor didn't clear the fault on the system...?

No, it's definitely the timing, hence the sensor code that won't clear.

Just now, sepulchrave said:

No, it's definitely the timing, hence the sensor code that won't clear.

Please note - The fault wasn't cleared on the system by the person who fitted the sensor - it didn't clear and then come back, the sensor was fitted and I'm pretty sure the fault wasn't cleared on the system before I drove away....

27 minutes ago, Drewphotoboy said:

Yes!

They are leading shoes when facing downhill and trailing shoes when facing uphill.