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Robert, UK Qualified Car Technician
Category: Car
Satisfied Customers: 4340
Experience:  Fully qualified / self employed garage technician in the UK
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I have a Vauxhall combi van which very recently had a full

Resolved Question:

I have a Vauxhall combi van which very recently had a full engine overhaul, new injectors, turbo, valves, piston to the tune of £2000+. On Friday after about 20 mins of driving the exhaust overheated to the extent that a fire broke out on the exhaust hanger rubbers causing a fire brigade call-out! The exhaust now shows a white residue in the tail pipe and in general looks cooked! The van has only done less than 200 miles since the engine work was done.
The garage when told about this stated the cat had failed and become blocked and that caused the temperature rise. The engine seemed to be running ok at the time of this fire though.
Any theories as to the cause and are the garage being honest?
Submitted: 1 year ago.
Category: Car
Expert:  Robert replied 1 year ago.


Hopefully i can help..

From the beginning - what was the intial fault & reason / tests carried out for a full engine rebuild?

Customer: replied 1 year ago.

The engine just packed in without warning. Various people looked at it and all said it needed a new engine! It only had 44000 miles on the clock!

I had some work done on my Chrysler by this garage so had them look at the van. They suggested reconditioning the engine as a more reliable option than buying one from a scrapper or cheaper than buying a new block and having to then buy new injectors, turbo etc.

They have all the equipment needed to do this so it was all done in-house.

Expert:  Robert replied 1 year ago.


Ok.. If the cat had actually blocked or collapsed internally or caused a restriction in the exhaust system this in turn can cause the exhaust system to overheat to the point that it would become red hot or glowing over period of time during use..mainly at the engine end to towards the blockage and this in turn could set fire to under the car or anything in the vacinity like your rubber exhaust the rest of the exhaust would be fairly cool..added to that a restriction in the exhaust too can actually cause lack of power or a complete non start situation depending on the extent of the a way that the blockage causes too much back pressure...bit like some one sticking something in the tail pipe the engine wont fire up...That why i was wondering if this wasnt the initial problem to begin with if they havent touched the exhaust to date.Many things could cause a blockage from external damage / oil/antifreeze contamination entering the cat / or the engine has been overheating / possible missfuelling....I do hope this helps..If you require to ask anything further then please continue before you rate

Robert, UK Qualified Car Technician
Category: Car
Satisfied Customers: 4340
Experience: Fully qualified / self employed garage technician in the UK
Robert and other Car Specialists are ready to help you
Customer: replied 1 year ago.

So basically the garage can tell me its the cats fault and not the fault of the reconditioning work. it just seems strange to me that the cat was ok before the engine packed in and within a short time after the reconditioning work it collapses. The AA recovery guy suggested that un-burnt fuel had entered the exhaust and that made me wonder.

The exhaust had white deposits in the tail pipe, if these were from the cat then it cannot have been blocked, could it?

Expert:  Robert replied 1 year ago.


Well a Cat doesnt collapse or block up through that short space of time without any performance issue..this is something that builds up over period of driving or during a intial fault with the car prior to failure - if fuel had entered the cat or the exhaust then you would have thick white/dense smoke,diesel smell - low mpg or even diesel fuel spots over the back of the vehicle or around the tail pipe...if an overfuelling issue was the case to cause that you would have incomplete combustion again..missfiring / dense smoke out the back - if its was overfuelling through a failing injector then normally diesel gets into the oil sump - mixes with the engine oil and overfills it,that could certainly cause oil/fuel to get into the exhaust system./blow internal oil seals due to the high volume of oil/fuel mix - white deposits is normally an ash substance maybe cause by the overheating burning through the build up of soot off internally....From my understanding anyway..and from what you have said - it strikes me - as nobody has actually tested and come up with reason for the failure in the first place " in regards ***** ***** actually was found/reason to cause the engine to pack up" - decided to rebuild the engine with a whole load of expensive parts without any evidence to back it up wether it require to be or not..and now there maybe the slightest possibility this could of been a restriction on the exhaust system that eventually got to the point where the engine lost power cut out and wouldnt start - only way they could of checked was to drop the manifold and start the engine ..if it ran then you know the exhaust was at fault..

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