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Discussion Starter #1
My Vi has started to lose power and now and then it seems to lose all power at about 4000 revs for about half a second but then picks up after that. This has only just started happening. Also it has recently started to use quite a bit of oil. There doesn't seem to be any obvious leak and the coolant is clear and there is no sign of mayo on the oil filler cap. Has anyone got any ideas as to what could be causing this? I checked the air filter but it seems fairly clean. The plugs and leads were only changed about 1,000 miles ago. Could it be the fuel filter?

Any help would be appreciated.
 

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Discussion Starter #6
Could be valve stem oil seals, is there any blueish smoke from the tail pipe?
I haven't noticed any blueish smoke from the tail pipe but i haven't really been looking for it. I will check in the morning, thanks for your help.
 

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It's just a suggestion, it could also be worn piston rings allowing oil to escape past and also loose compression making you down on power. Get a compression test done on the cylinders.
Also have a look in the air filter for any oily residue.
 

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Discussion Starter #10
I couldn't see any oily residue in the air filter but i removed the air intake pipe from the throttle body and had a look in there. There was quite a bit of oil inside. Does this still sound like worn piston rings?
 

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I couldn't see any oily residue in the air filter but i removed the air intake pipe from the throttle body and had a look in there. There was quite a bit of oil inside. Does this still sound like worn piston rings?
Looking more and more like worn pistion rings, get the compression test done. Worn piston rings could cause pressure in the crankcase causing blow back through the breather and into the intake.
 

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Discussion Starter #12
Looking more and more like worn pistion rings, get the compression test done. Worn piston rings could cause pressure in the crankcase causing blow back through the breather and into the intake.
Thanks, i will try and get a compression test done next week.

If it is worn piston rings, is it a big job to replace them and how much is it likely to cost?
 

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If it is worn piston rings, is it a big job to replace them and how much is it likely to cost?
If it does turn out to be piston rings, replacement is going to be expensive.

What mileage has the car done?

The piston rings are what the name implys. They go around the pistons to seal the compression in the cylinder and to hold oil between cylinder walls and piston etc etc.

Unfortunately they are very deep inside the engine, the engine will have to come out of the car and a complete strip down/rebuild performed. Because of the amount of work it may be worth budgeting for a fulll rebuild with all parts worn being replaced while its apart.

If your keeping the car it may be worth doing. Dont hold me to this, but im sure that a piston and ring set for these engines is in the region of £400. This is just parts alone!

Are you going to do the compression test yourself? You can pick up a gauge from motor factors for about £20 and doing the test is about as easy as changing a spark plug.
 

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Discussion Starter #14
The car has done 105,000 miles. I haven't got a gauge to do a compression test so i think i will ask a garage to do the test, it will probably be cheaper than buying a gauge. £400 seems a lot of money just for the parts. If i continue to use the car is the problem likely to get worse or cause other problems?
 

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The car has done 105,000 miles
Thats not extreme mileage. Im suprised the rings are worn so early on.

If i continue to use the car is the problem likely to get worse or cause other problems?
If you keep the oil topped up fully and dont caine the car everywhere you shouldnt have a problem. As a guide, keep the revs below say 4000rpm.

Forgot to ask, does the car make any noises like ticking or knocking?
 

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If it is piston rings then the engine may have had a hard life. It's probably not worth a rebuild, thicker oil will help 20w/50 and maybe some Wynns smoke stop.
The VVC should really have 10w/40 in it, it's your call.
 

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Discussion Starter #17
Blue smoke started coming out of the exhaust over the weekend. It also started to misfire. I checked the spark plugs and one of them seemed to be covered in a black, oil-like substance. I checked the air filter again and there was a lot of oil in there.

I was worried about causing more damage by driving it so I phoned the RAC to get it home. They done a compression test and there was hardly any compression on one of the cylinders (the one with the oily spark plug) and another one was low. They said it was probably head gasket or piston rings.

The oil and coolant haven't mixed and the coolant level hasn't changed, only the oil level has been going down. Is this looking like it's the piston rings?
 

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Best just to take the head off and go from there. You are going to have to do it no matter what then you'll get a better look at the problem. It could be HGF, but it would be unusual for just the oil to drop and not the water.
 

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Discussion Starter #19
I've taken it to a garage, they are taking the head off today. They said if it's the head gasket it will cost about £250 to change, which seems quite reasonable to me. They said if it's piston rings, seals etc it would be a lot more and possibly not worth doing.

They said they regularly do K series head gaskets and they use the head gasket sets with the steel dowels and have never had one fail after being fitted.

Ashy, i seem to remember reading somewhere that you have a Vi with over 100,000 miles on it. My Vi has done 105,000 miles so if turns out to be the piston rings etc do you think it's worth repairing? I would like to keep the car for at least another couple of years so if i'm likely to get another 50,000 miles out of the engine after having the work done then i wouldn't mind.

The other thing i am thinking is how long are the VVC mechanisms likely to last? I could get the engine repaired only to find the VVC mechanisms dying soon after. I look after the car - frequent oil changes, check levels, always let the engine warm up before using high revs, but it had done 94,000 miles before i bought it so i don't know how it has been treated in the past.
 
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