Strange tapping/slapping sound.....HELP!

[Gütterßnipe]

On a 60 mile motorway journey today - 15 miles in I noticed that when I increased the revs this slapping/tapping noise appeared - then when I took my foot off the gas - the noise stopped......
I pulled over and took a look out back with the engine running and again the noise only appeared when the throttle was opened :?
I checked the oil and added about 300ml - job I should have done about a week ago then decided to carry on with my journey.
The the noise went after about another 10 minutes then came back again when I had to increase revs to get up a hill, then once at the top it gradually disappeared.....

Funny thing is......The performance doesn't seem to be affected?

Then the last ten miles of my journey it re-appeared, lower revs on B roads through all gears - although not there when just ticking over - it almost sounds like I've got a hole in a manifold - strange as new manifold/box only fitted 10 months ago....

Any clues/ideas/help appreciated.....????

Spence

 

[mattyd72]

Have you checked your timing recently, it may be out??
Perhaps a loose head which blows under throttle?


Sent from my GT-I9100 using Tapatalk 2

 

[slow-lane-Matt]

Could it be your CV joints...? They can clank when you accelerate or slow down.
edit (Forget this - didn't read properly can't be this if happens when pulled over!)

 

[Bay-low71]

Have a look here.... Very good site,

http://www.vct2.nl/vwtech/Pages/Engine%20Health%20Check/Noise%20Diagnosis/Engine%20Noise%20Diagnosis.htm" onclick="window.open(this.href);return false;

Have you had any engine work done recently?

 

[aogrady]

Hi,

Sounds like a loose exhaust, blowing/holed/loose heads?

Maybe loose or warped cooling fan, though reckon exhaust...

Alistair

 

[dustrat]

Diagnosing noises with out hearing them is just guesswork. Recentley a friend of mine who has a type 2 had a simular type of noise coming from his engine.It turned out to be the nut that holds the fan onto the alternator inside the fan housing had come slack.This might not be your problem but its worth checking.
Bob
:idea:

 

[Gütterßnipe]

Cheers for all of the replies!

Driving back late last night with my wife and daughter asleep (nag-free zone) I think and hope the sound is exhaust related - again no real change in performance just nasty and loud...

One thing I did notice though - the sound is far more prominent when accelerating and dies off once I've reached a constant engine speed whether it be 2000, 3000 etc...

Would an exhaust problem cause that????

Confused????

Spence

 

[betsy70]

had the similar problem few years back same thing noisey tapping sound but not really loosing any power, when travelling europe took my bus into BBT in belgium and the noise turned ou to be a pushrod it had melted the tip and the rod was shorter than all the others , very simple fix but no idea how it happened . after fully checking evrything else , gaps timing etc replacing the damaged rod , it ran like a dream .

 

[Gütterßnipe]

had the similar problem few years back same thing noisey tapping sound but not really loosing any power, when travelling europe took my bus into BBT in belgium and the noise turned ou to be a pushrod it had melted the tip and the rod was shorter than all the others , very simple fix but no idea how it happened . after fully checking evrything else , gaps timing etc replacing the damaged rod , it ran like a dream .

Ouch!
Did you only get this noise upon increasing revs??

I think I'll check the exhaust first.... Don't need engine work on the run up to Xmas but
Thanks for the heads up!

What will be,will be!

 

[ozziedog]

Does sound like zoorst is making veiled threats about shuffling off its non mortal coil :shock: Usually a way around though. If you run it up to a decent speed in any gear then take your foot off the go pedal and let the engine slow you down using engine braking do you get a lot of popping and banging ??????????

Ozziedog,,,,,,,,,,,,,,, Lets hope it is :mrgreen:

 

[betsy70]

yes when on idle it sounded sweet as a nut lol , wasnt a dear fix tho within minutes of the guys at BBT listening to my engine they sorted it its any easy check just pop off the rocker covers and if a rod knackered youll see it .
hopefully its just your exhaust tho .

 

[Gütterßnipe]

No popping or banging - my whole exhaust system plus heat exchangers are only 1 year old :?
Still I'll try to kill the engine by putting a wet rag over the tailpipe to see if there are any leaks...
Will check under the rocker covers for a knackered pushrod....
**** knows what I'm looking for......out comes the Bentley manual me thinks!

I LOVE WORKING ON MY BUS IN THE GUTTER