Engine knocking noise from Audi A4 1.8T - diagnosis?

MarkDavis

MarkDavis

MarkDavis

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Went with a mate to have a look at a 2001 A4 1.8T earlier this evening.

Dealer says that the car has a fault with the engine. Basically there's an intermittent knocking / rattling / tappety noise coming from the engine. It definitely doesn't sound healthy when the knocking comes on. It sounds like something hitting something internally that it shouldn't be.

The dealer says it could be the oil pump or pressure valve and does not recommend driving it for any great distance in case the pump fails.

If its historically had an oil pump failure, presumably this would cause the engine damage. If so, can these engines rebuilt, and if so, at what cost? What the likely cost of a recon'd replacement 1.8T engine?

In a best case, and worse case scenario, what could it be and how much could it cost to get it fixed?
 
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I would steer well clear of cars showing those faults, unless they are doing it rediculously cheap so you could factor in a new engine at roughly the right money.

But as they are not rare I would just look for another one somewhere else and save potential major hastle sooner or later...
 
Pump failure doesn't usually sound like a tapping sound in my (rather limited) experience, more usually a whine of some sort.

Could be a number of things, is the engine chain driven ? ...if so, could be chain slap from a slack chain caused by a faulty tensioner, big end on the way out, lifters ...even an exhaust leak can sound a bit like a rattle/tap.

I have a tap in my engine right now, I have a few ideas about what that could be though.

Does your engine have any sort of cam profile switching do you know ?

Also, most obvious one, has it got enough nice clean oil of the correct viscosity in it ?
 
Decent dealers don't sell faulty cars that are easy or cheap to fix. They fix them first and get a better price.
 
Walk away. If it needs a rebuild it will be expensive, it usually costs less to drop another engine in, expect £300-400 labour from a normal garage, not a dealer then the engine will be anywhere from £600 to £800 I would imagine.

Then what if you have more problems, the costs could spiral upwards, just look for a better example.
 
The oil pickup in the sump is blocked causing the top end to knock, the knocking noise should be comming from the back of the rocker cover, the cam chain tensioner isn't getting any oil causing the VVT chain to run slack, this makes the whole lot knock.

If the garage have run this for a while the turbo and tensioner will be on the way out, the VVT tensioner cost me £300+ just for the part (depends which one your engine needs).

To drop the sump and change the pickup cost me £275 in Germany.

In summary unless the car is mega cheap walk away.
 
MarkDavis said:
Went with a mate to have a look at a 2001 A4 1.8T earlier this evening.

Dealer says that the car has a fault with the engine. Basically there's an intermittent knocking / rattling / tappety noise coming from the engine. It definitely doesn't sound healthy when the knocking comes on. It sounds like something hitting something internally that it shouldn't be.

The dealer says it could be the oil pump or pressure valve and does not recommend driving it for any great distance in case the pump fails.

If its historically had an oil pump failure, presumably this would cause the engine damage. If so, can these engines rebuilt, and if so, at what cost? What the likely cost of a recon'd replacement 1.8T engine?

In a best case, and worse case scenario, what could it be and how much could it cost to get it fixed?
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Sounds like a job for AA breakdown repair cover. Buy it, wait two weeks, drive it until it fails, and save yourself a few hundred quid.
 
Yes, i'm going to buy a 355 with impending valve failure and get the AA to fix it for free.........

Care to tell me how your plan would work exactly?
 
Firestar_3x said:
Yes, i'm going to buy a 355 with impending valve failure and get the AA to fix it for free.........

Care to tell me how your plan would work exactly?
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He'd be well within his rights to call the AA out because the car is making a very funny noise, and if they can't fix it at the roadside, they'll pop it to a garage for you. If they replace the oil pump, great. If the problem isn't fixed, claim again. And again. And once more for good measure if the problem's still there. For the cost of AA cover + Breakdown Repair Cover, he can get them to pay for his diagnostic work. If it does blow up in the meantime, and it does cost more than £500 he'll still have saved a few hundred quid. Which, incidentally, is what I said in my first post. I didn't said it would be free did I? Care to be a little less patronising for a while? Kthx.
Janesy B said:
Don't think a new engine will be under £500 :)
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I didn't say it was :). I said it would save him a few hundred quid, not that it would be free :).
 
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