Tapping noise

Nissan Navara Forum

Help Support Nissan Navara Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

amw77

Member
Joined
Dec 1, 2011
Messages
16
Reaction score
0
Location
Bellmere, QLD
Hey guys, just new on here so feeling my way around. I have a 2007 D40 and it has started to make a tapping noise from the motor, i'm not really mechanically inclined so i was wondering the best thing to do? I read one post that said something about a VNT solenoid? Don't even know what that is! It sounds to me like a tappet noise.
 
Last edited:
The answer could be different for petrol or diesel engines.

Petrol engines tapping away in the top of the motor usually means valve clearance or a loose cam chain. There are not many reports of the petrol chain tensioners causing problems but things do get old!

Diesels make a bunch of extra noise. The injectors alone make a racket, they also have camshafts and therefore have both chains, tensioners and shims. If it was your turbocharger's actuator you'd hear a thumping more than a tapping sound.

If yours is a manual, what many people (with D40 manuals that develop tapping noises) have found is the hydraulic line heading to the gearbox along the firewall is too close to the firewall and it taps while the engine is running. Put a piece of packing foam in behind it to see if that's it and if it is, get someone to reposition the lines if you don't feel confident doing that yourself.

Either petrol or diesel could have an issue with the cooling fan, either chipped blade or nicking the shroud - or worse, the radiator itself, and that'll be disastrous. I don't think the water pumps generally make that sort of noise, they either shriek or grind their way into oblivion.

I suppose if it's not hugely loud it could also be related to the EGR valve, cycling open and closed through some fault - if the EGR valve opens at idle you'll know it, the engine will run really rough or it will stall.

There's a few things to start with anyway.
 
The vnt part gave away that it's a diesel...

Give us an idea how this noise related to engine rpm. As fast /frequent as the revs or way slower? Whirring type noises come from the pulleys (alternator), in a lot of cases, while tapping noises may indeed just be the injectors. Try to pinpoint as much as possible, where in particular in the engine bay you hear the sounds coming from. If it 's the injectors, adding up to 200ml of mineral based two stroke oil to every tank full may help.
 
Hey mate. It doesn't seem to be doing it at idle, i only hear it when i am accelerating. Seems to rise and fall with the revs, and also seems to get a bit quieter after about 10 minutes of running. Does this help at all?
 
Sounds like a mix of cold injectors + lower cetane fuel.

Try running a tank of BP diesel through it. You wouldn't suffer any bad effects giving the 2-stroke a try, but make sure it's at least JASO-FC or better - Castrol Activ 2T works nicely.
 
Cheers guys, i appreciate the help. I always us bp diesel whenever i can. The car has done just over 100,000 kms. No chips or anything that i know of anyway. Seems like i am leaning towards the injectors by what you guys are saying. You guys don't think it would be the timing chain, or oil pump? Thats just another couple of options that i have read on here as possibilities. I wanted a good opinion before just taking it to someone and getting ripped off.
 
Start with the injectors first, as it'll cost next to nothing. 200ml of two stroke as described earlier, plus a reset of the ecu /fuel pump learning curve (search the forum for how to do this).
 
At 100,000km it would be needing a timing/cam chain (what is it called on a diesel?), don't have one snap on you, one of my work van's just did a timing belt at 101,000km $1500 to fix it for cash, dare say a D40 Diesel motor would be a bit more than the mitsi express
 
Rich, that's entirely likely, but I'd have thought the sound would be more like a rattle rather than a tap which is why I mentioned the chains in passing only.

Maybe we should ask people to upload small recordings of these things, it's helped in the past!
 
At my 100,000 klm service i asked them to check the chain and they said it sounded ok. So i just pour the oil in the tank when i fuel up?
 
Hi there guys,

Sorry to hijack the thread but it sounds like I have the same issues. Its a 06 d40 T/d ST-X. IT tap is much worse when cold, and only subsides when its really warmed up, but is still there when you put your boot into it when warm. It rises and falls with revs. Its done 70 000km. I've just put a load of injector cleaner in the tank, but has made no difference.

With regards to putting 2 stroke oil in the fuel, as you saying put 300ml in an 80L tank? Wont it smoke like heck?. Is it worth waiting untill the tank is down to say a quarter full and then put the right amount in?

Thanks in advance guys
 
It doesn't smoke with that much 2-stroke. 2-stroke oil in diesel fuel is a chemically different thing to 2-stroke oil in petrol. Diesel itself is oily, whereas petrol feels like a solvent. They are not the same thing, and the 2-stroke changes the lubricity a little and changes the combustion characteristics as well.

Mine taps away a fair bit - late 2009 model with 91,000km on it and a lot of that with a 1.8T van behind it. It seems worse in the cold, and for my money that means letting her warm up a little more. I'll throw some 2-stroke in my tank when I fill this time (500ml for 150L sounds ok to me) and we'll see how that goes.
 
Just a follow up, I have put about 200ml of 2 stroke oil in my tank when it was approx quarter full, so say 50L of diesel. Didn't seem to make a bit of difference, still taps like mad when it's cold and its not until she is really warm that the noise reduces. It's still slightly there when warm, but this may be normal noise.

Any other ideas? I hooked it up the the engine scanner I have access to to try and look at individual injectors ( you can do this with the Toyotas) but the scanner didn't let us do it. I also have the ability to switch off individual cylinders so to see if the injector noise stops, but the motor was warm so the difference was not noticeable. I will try again tomorrow morning when the engine is cold to see if it's a dodgy injector
 

Latest posts

Back
Top