# Tappet like noise at 2000RPM - Petrol Injector?



## The Mad Hat Man (Oct 3, 2006)

Ever since I had my 2002 X-T (about 30K miles ago) I have had this annoying rattle from the engine. It occurs on load and seems to cut in about 200RPM. On overrun it disappears and also seems to get quieter about 3000-3500RPM. It is more pronounced when cold, but still there when warm. I mentioned it to Nissan just after i bought it and the response was "cant hear anything". It is still there, arguably it cant be that bad (small ends? ) but it is frustrating not knowing what it is. My assumption is "it wasnt designed with it - it cant be correct".
Whilst perusing another forum, I saw mentioned the issue of "injector knock". I gather this is a known problem with the diesels, but does anyone have any experience of it on the petrol X-T's (mine is a 2.0). Is there a way to identify if that is what the noise is? I have a generic fault reader, but nothing is shown, but I can read "live" data, if I knew what to look for. If it is injector knock, can it be traced to one injector? Is it a case of having them checked - or replaced ?


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## aussietrail (Sep 24, 2004)

I'd get the dealer to check the timing chain tensioner.


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## The Mad Hat Man (Oct 3, 2006)

Thanks Jalal - is this a common problem on the 2.0L petrols?


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## The Mad Hat Man (Oct 3, 2006)

Well.................

Its been a long time, but I think I might, just might, have found the source of this noise.:woowoo:

As I said, I had this noise since I had the car. The only response from Nissan has been either "what noise" or "some engine have their own noises" :lame::lame:, but took the car to a non dealer today and they had a quick listen....... "sounds like exhaust to me" they said, quickly followed by "have a look at this".

As can be seen from the attached pic, the exhaust manifold is cracked (or splitting) by the pre-cat sensor (the black carbon deposit). Looking on the AU site, I get the impression that this is not uncommon.










Cant it be welded, or is it a new manifold/cat? Understandable, I would rather it was the former.
Is it usual for all the heat shield bolts to shear ?

Any tricks, guides, help, folks?


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## The Mad Hat Man (Oct 3, 2006)

Oops

Be aware - this can happen very quickly .

this what it should look like....









Not this.......









you can see from this pic, exactly how little weld was keeping it attached - the small piece at about 11:00 ....









This is what it looks like now - after a touch of Tig......









Although it cant be seen very easily, it is only the boss that has been welded back on to the manifold - I didnt want to risk damaging the sensor by trying to remove the boss.


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## The Mad Hat Man (Oct 3, 2006)

more info - it didnt actually fix the engine "ticking", So i am thinking it must be a sticking cam follower....


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