Intercooler Hose/ Engine Tone

[Denny57]

Dear all

I've just found this forum it looks great and a really useful resource
I have owned 5 VW Diesels over 18 years e.g 2 Jetta MkII and 2 Passats (Hatchback)
Currently I have a 2002 Passat Estate 130TDI owned since June 2005 with 150k on the clock with Full Dealer Service History.

About 6 months ago it began to make a noise similar to a slight exhaust leak and then recently the large Intercooler hose burst and I lost power.
My mechanic quickly found the problem and replaced the hose he also found a lot of gunge in the inlet manifold but no exhaust leak.
He was however concerned about what might have caused the hose to burst in the first place but wasn't sure.

I now have the car back and although it runs great it still has the unusual tone to the engine, although this may be unrelated I still feel it might have a baring on the hose failure.

If anyone can comment I would be grateful

[brogandb7]

Hi Denny,

Thought I would compile a list of things for the members in general. Here's some items that might be a useful point to start a process of elimination...

Motor Noise: Muffler Explosions
Possible Causes
Mixture not exploding regularly
Exhaust valve sticking
Dirt under exhaust valve seat
Sticking breaker points
Ruptured muffler

Motor Noise: Popping or Blowing in Carburetor
Possible Causes
Not enough gasoline (open needle valve)
Spark retarded too much
Weak battery
Incorrectly timed inlet valves
Inlet valve not seating
Defective inlet valve spring
Dirt under inlet valve seat
Pitted contact points on timer

Motor Noise: Hissing and Squeaking
Possible Causes
Poor lubrication (causes squeaking)
Leaking or ruptured muffler
Leaking around spark plug
Leaking cylinder head packing
Loose joint between motor and exhaust manifold
Loose valve spring chamber cover
Broken insulation on spark plug
Broken piston rings (blowing sound)
Tight piston rings (scraping sound)

[Dave Elcome]

The above list does seem fairly comprehensive, but your noise may well be much simpler to trace.

My 130 TDi developed a similar noise to that which you describe, after not too much hassle I traced it to a poorly fitting air intake hose onto the air filter body. I can only assume that with time, and numerous removals to change the air filter, that the retaining mechanism becomes weak, the end result being that no matter how many times you push it back into place, it 'rides up' in use, it only needs to move by about 1/2 inch max to give the induction noise, you can also see on mine where it has rubbed on the underside of the bonnet.

I suppose I could splash out on a new hose, what I in fact did, was to fix a piece of foam on top of the offending hose, such that when to bonnet is shut it applies a light enough pressure to push the hose onto its correct mounting position.

[Denny57]

Hi Brogandb7 and Dave

Thank you for the Fault List and possible solutions I'm sure some will apply to my engine although it's a diesel, I'll certainly check the exhuast.

If there isn't already one on this website your list might be used as a basis for a more comprehensive stock faults and solutions list.

and thanks Dave for the info relating to the new engine tone I will have a closer look at the air intake.

Many Thanks to both of you for taking the time to reply

Denny

[dannyboy68]

although this is a very late response, it may help others out there. i spent many years working with agricultural turbo deisels (fendt and massey ferguson, to be specific) and and whenever an intercooler line ruptured it was from being saturated with engine oil ( incompatible lubricant for the hose material ).

oil from a leaking turbo or issues with exhaust gas recirculation ( usually the problem with the fendts ) let oil into the intake system and would soften and swell the hoses until they burst.

so, anyone with a turbo car and spongey hoses, look for a sloppy turbo bushing or plugged EGR system.

dan

[Denny57]

Thanks Dannyboy

I have now sold the car but before doing so had found out that my mechanic had botched the intercooler hose replacement causing me so much trouble.

I got some money back from him and had the hose replaced at another garage

I gave all of the details to the purchaser

Many Thanks once again

Cheers

Denny