The cam timing had jumped initially and the retarded valve operation created a noisy exhaust which was possibly misdiagnosed but it is possible that the intense heat could have damaged the catastrophic convertor.

 

The cam timing sensor was replaced in error as the problem was actually slipped timing, I have some sympathy here as most garages would replace the sensor first to rule it out and its a cheap easy repair if it was faulty.

 

You took the car back and the timing has slipped further after the vehicle creeped on the handbrake while parked in gear.

 

You now have an undriveable vehicle.

 

How much if any of this is the responsability of the repairing garage is difficult to say.

 

Can you explain what you meant by "While away from home" you and the car or just yourself?

Just to be 100% clear the person who fitted the new cam sensor didn't connect a diagnostic reader and clear the fault before I drove away....

1 hour ago, Drewphotoboy said:

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

 

2 hours ago, Drewphotoboy said:

very noisy exhaust, virtually no power.

 

If you were away but not the vehicle then you would not have heard & felt the indications.

4 minutes ago, J.R. said:

The cam timing had jumped initially and the retarded valve operation created a noisy exhaust which was possibly misdiagnosed but it is possible that the intense heat could have damaged the catastrophic convertor.

 

The cam timing sensor was replaced in error as the problem was actually slipped timing, I have some sympathy here as most garages would replace the sensor first to rule it out and its a cheap easy repair if it was faulty.

 

You took the car back and the timing has slipped further after the vehicle creeped on the handbrake while parked in gear.

 

You now have an undriveable vehicle.

 

How much if any of this is the responsability of the repairing garage is difficult to say.

 

Can you explain what you meant by "While away from home" you and the car or just yourself?

Hi - Thanks for all your help. I sometimes work away and had the CAT and Sensor replaced while away and then retruned home (100 miles drive) drove around town at low speeds for a day OK then the following morning it wouldn't start.

So the concensus is the timing is now so far off it won't drive...

If this is the case what is your advice as to how I should procedd  - I only have fairly basic skills.

Also am I likely to have damaged the valves?

Should I not turn the engine over??

The significance being that its a garage where you are an unknown new customer and too far away for you to tow the car back to.

 

I think given the circumstances and the distance you have no choice but to accept that they were working in good faith and had unknowingly accepted an already damaged smoking gun into their workshops.

2 minutes ago, J.R. said:

The significance being that its a garage where you are an unknown new customer and too far away for you to tow the car back to.

 

I think given the circumstances and the distance you have no choice but to accept that they were working in good faith and had unknowingly accepted an already damaged smoking gun into their workshops.

I think garage were legit and did a good job -  I've used them a couple of times before as I visit there frequently, they just forgot to reset the system after quickly fitting the cam sensor before I drove away, this was a last min addition to the job...

Quick (posibly stupid) quest - is the cam timing on a belt or a chain on this car??

My takeaway here is that leaving car in gear on hill when you've only got drum breaks on rear wheels is a no-no as it too much force will act on timing chain and could cause it to jump or slip??

Thanks again for your help so far...

• What is your advice as to how I should proceed
• I only have fairly diy basic skills
• I could check plugs/cylinder but not about to undertake a rebuild...
• Am I likely to have damaged the valves?
• Should I not turn the engine over??

1 hour ago, Drewphotoboy said:

So the concensus is the timing is now so far off it won't drive...

If this is the case what is your advice as to how I should procedd  - I only have fairly basic skills.

Also am I likely to have damaged the valves?

Should I not turn the engine over??

Finish the diagnostics with TDC check before making any assumptions.

Chain timing on the HTP engines.

Edited 15 July, 20232 yr by Breezy_Pete

OK - I've just had the emergency call out guy here:

• He first reset system and cleared the Cam Fault - when restarted it was still there.
• He cleared the system again and nothing else was showing but the cam sensor fault
• He suggested the new sensor was likely fine and the error was due to cam/crank misalignment.
• He turned the engine over and squirted 'solvent' into the air intake - the engine didn't catch at all.
• He listened to the engine and felt that the engine turned over too easily and quietly suggesting low compression.
• Also suggested that if it had previously jumped just one tooth it might still run but burn hot and over time kill the cat.

His diagnosis is the same as yours - a timing issue - jumped a few teeth. He suggested:

• Tow to a nearby garage
• Strip down timing chain
• Reset timing (without replacing with new timing kit) to test engine.
• If engine runs OK fit new kit and all is well.
• If engine doesn't run due to damaged valves/pistons consider if car is worth spending big money on.

I think I might remove plugs and test cam alignment at TDC to double check (he said he wouldn't bother as he is certain this is the issue).

This all seems about right to me  - any comments....? (And as a newbie thanks for your very helpful advice!)

 

1 hour ago, Drewphotoboy said:

I think garage were legit and did a good job -  I've used them a couple of times before as I visit there frequently, they just forgot to reset the system after quickly fitting the cam sensor before I drove away, this was a last min addition to the job...

The fault code is an indication that the ECU detected a problem. Resetting a fault code will not make the fault go away. Not resetting a fault code after repairing the cause will not cause the fault to re-occur. This is a red herring here.

8 minutes ago, chimaera said:

The fault code is an indication that the ECU detected a problem. Resetting a fault code will not make the fault go away. Not resetting a fault code after repairing the cause will not cause the fault to re-occur. This is a red herring here.

Thnaks Chimaera - I was concerned that not reseting system after replacing part might have made the ECU 'unhappy' and caused other problems but clearly not - I think I have the answer (see above)

You can't run the engine with timing cover off, so that aspect of mechanic's plan can't work, I think.

 

And it's hours of work to get it off and on again.

Edited 15 July, 20232 yr by Breezy_Pete

First thing is to verify the timing.

 

If the timing is off far enough, the engine will lose compression because the valves are out of sync and it's impossible to get all the valves in any cylinder to close fully. So we don't worry about compression yet.

 

Second thing is to use a borescope to check the condition of the pistons. If they have hit valves they will be marked.

 

If the pistons look good then I think it's worth a shot at sorting out the timing. You're as well off fitting a new chain and tensioner once you get in there, given the labour involved.

Thanks Chimaera and Pete for advice.

So Check TDC myself (and perhaps see if I can get a photo down plug hole to see if any damage).

Then tow to garage to check diagnosis and put new timing kit on as its not worth not replacing if stripped down to reset timing.

Then fingers crossed...?

Check alignment of cams at TDC then do a compression test to confirm the worst case, no need to pay a garage a fortune to tell you that the car needs head off, new valves, piston & bore inspection and a new timing chain, tensioner & guides when you can do all that yourself and wont be putting yourself in a ransom situation where they have your car stripped down.

11 hours ago, Drewphotoboy said:

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....

 

Please note - what you are suffering from is called denial.

 

Your timing has slipped, the chain has skipped on the crank sprocket, you can check this quite easily by following some simple instructions.

Finish the diagnosis.

Chances are high that valves will have been bent if chain has slipped on crank sprocket, so I doubt it's worth repairing. Get quotes for this scenario to help you decide. 

I think @Crasher may be near or in Nottingham, and might be prepared to give you a ballpark idea. 

Edited 16 July, 20232 yr by Breezy_Pete

4 hours ago, Breezy_Pete said:

 

I think @Crasher may be near or in Nottingham, and might be prepared to give you a ballpark idea. 

 
Right in the middle but booked solid for a month minimum 

UPDATE

I've had the plugs out and checked TDC as suggested.

The cams are both aligned with one another however at TDC they are diagonal (at approximately 7-2 o'clock) rather than dead horizontal (9-3 o'clock).

See below (camera is level at TDC - apologies for the distracting bracket in the foreground)

 

 

So this confirms the problem as you've all advised - timing chain has jumped on crank sprocket.

I think it probably jumped a single sprocket a while ago which resulted in incomplete combustion, poor performance and overheating which killed the CAT ?

Then this week after parking facing up steep hill and leaving in 1st gear its jumped again to the extent that it won't run.

As this is an interference engine this will have probably damaged the valves.

 

I've reviewed GREGSY's experience here:

 

https://www.briskoda.net/forums/topic/497626-has-my-timing-chain-skipped-any-easy-way-to-check/

 

Given my car is outside on a steep hill and I have no workshop, this kind of repair is beyond me so I'm going to ring round some recomended garages tomorrow.

 

I know in the past that you've advised this kind of fault is probably not worth reparing (2021)

 

https://www.briskoda.net/forums/topic/498056-skoda-fabia-2003-12-htp-117000-miles-engine-turning-over-quickly-but-not-starting/

 

Given the current price of second hand cars and the fact I've had the car since new and it's otherwise sound would this still be your advice... ??

 

Thanks again for all your help in diagnosing this - at least now I know what's wrong despite the challenge of getting this fixed (and I've learned not to park facing uphill and leave in gear....!)

I would buy, beg  steal or borrow a compression tester.

 

It won't show full compression with slipped timing but if it shows any on all 4 cylinders then you have dodged a bullet and the car is economically repairable. 

Thanks - I will do that....

 

2 hours ago, J.R. said:

I would buy, beg  steal or borrow a compression tester.

 

It won't show full compression with slipped timing but if it shows any on all 3 cylinders then you have dodged a bullet and the car is economically repairable. 

 

FYP.