whist mapping today we noticed the car was detecting a sound, its a very quiet ticking sound that is only heard at low revs 1000/3000k. It geos away when on boost but was enough for the ecu to notice and sometimes log and put into limp mode.

Has anyone had this before I have noticed that there is a small crack about the size a cm long on my downpipe neck close to the turbo could this be the problem and cause the ticking sound.

any help would be great

 

boost solenoid maybe

 

BCS, injectors or alternator bearing are usual suspects

 

I hope its any of these would the above be noticed as a noise by the ecu.

Iv just taken it for a drive now its mapped and apart from the sound that is there sometimes but not all the time it drives spot on.

I thinking the ticking could be the crack but then I would of thought when it get hot it would close up

 

got mine remapped last month put a 3 port on sh@t my self when i was sitting in traffic with the radio off when i gently pressed the throttle i could hear a quiet ticking noise went under the bonnet and it was the 3 port

 

Is there any way of checking this, My worry is the ecu was detecting a noise and alot of the time putting it into limp mode thinking its DET we managed to map it and seems to be fine some of the time the noise isnt there im just a little worried as hoping its nothing serious. But the more I think about it the more it sounds either something silly like a boost controller or the crack in the downpipe

 

what did the mapper say it was? can he not hear it and identify it with detcans?

if the ecu was detecting it and pulling timing then it is most likely internal to the engine.. best case a valve clearance is a bit large, worse case ringland damaged or a bearing.. which sounds most likely from your description tbh..

Simon

 

the mapper said he could just hear it but didnt sound internal but wasnt noticeable on boost and very quiet off boost somtimes not there at all. Its sounds exactly like a ticking from a cracked exhuast, I have read that any noise like that can log a fault.

 

no the frequency of an exhaust leak is different and wouldn't cause a ticking noise that would cause the ecu to retard timing..
is the noise there if revving the engine at a standard still?

if so if you blip the throttle to 2500rpm and lift off does the tick increase in frequency or remain matching to rpm?

Simon

 

The only time I can hear the ticking is somtimes between 2000-2500k while driving the car the sound isnt there when bliping the thottle only a very small click now and then. The sound also deosnt get any louder with revs.

its sounds exsactly like a ticking you get from a manifold when its cracked

 

clock?

 

bomb with clock connected to it?

 

????

 

I think it is their attempt at humour

it is always possible the tick and the pulling of timing are separate events and it is only an exhaust leak.. but not possible to diagnose it from a txt description on here.. should be an easy thing to know when wiyh the car, or at least know an avenue to go down to help sort it.

Simon