Help!

[AllanOrr]

Hi guys ran into a small prob with the silvia over the last few weeks which is making my walet quite nervous, when i start up the car and put it into gear (this being any gear 1-6) and tap the accelarator there is a obvious crunching noise then after this it doesnt do it agen its only on the start up

me and some of the mechanics cant make out if its drivetrain related or engine? any of you guys came accross this before?
Also the engine is quite tappy had a wee look through the site and cant seem to find any info to figure out if the tappets or big ends and noisey on these cars. This car is still under warranty from Torque GT and has a month left aswell so dont know if I should go down the route.

If anyone can point me in the right direction would be appreciated guys

Cheers

 

[Roots82]

Sounds like it could be the start of VVT rattle. The SR20 motor is prone. Mine makes a slight grinding sort of noise when I first pull away or lift off the clutch and rev the engine.

It's not usually a problem that effects the engine. But try a search on here or the SXoc for VVT rattle and see if it sounds like your problem.

 

[LuPix_S15]

Yeah I get the grinding noise when I pull away sometimes... had this for ages so don't think it's a problem (AFAIK!!) :wack:

 

[tooley]

VVT rattle should only happen on a cold engine, my last 14a and 14 had it after they had done about 70k miles. (so ive been told)

It dosent effect the engine life or performance its just noisy.
My new 15 has a twin plate clutch and a 2 way diff so its noisy anyway but ive not got any vvt rattle yet.

I wouldnt describe vvt rattle as a crunching noise though its more of a metal vibration sound.

Waht do you mean when you hear a crunching sound? is it like a grinding sort of noise?

 

[richy200]

VVT rattle should only happen on a cold engine, my last 14a and 14 had it after they had done about 70k miles. (so ive been told)

It dosent effect the engine life or performance its just noisy.
My new 15 has a twin plate clutch and a 2 way diff so its noisy anyway but ive not got any vvt rattle yet.

I wouldnt describe vvt rattle as a crunching noise though its more of a metal vibration sound.

Waht do you mean when you hear a crunching sound? is it like a grinding sort of noise?

Completely agree with what tooley said and I have had loads of sr's with vvt rattle but i wouldn't describe vvt rattle as a crunching noise either more of what it says really a rattle which happens only on startup.

 

[sx-si]

sounds like the engines ****ed for a second?
vvt is ok especially when its only on start up but quite a while down the line it will just fail compleatly and sound like the engine is dead
when that happens just turn it off and go get a new one from nissan should be around 600-800

 

[Nicely]

Establish if it's coming from the engine or gearbox. If it's the engine, it's sounds like it's possibly the VVT. Depends what you define a crunching sound.

VVT rattle can occur other than at startup. If engine oil is low it will do it all the time. It'll also do it if the sprocket is well and truly fooked.

 

[AllanOrr]

a would say that sounds about right guys its more from the engine cause if i keep just lightly tapping the accelerator it vibrates simultaneously for a few seconds but mainly only on a cold start as yous said is there anyway to get the noise to go away as it realy is annoying or do you just have to wait till the engine heats up before going on your travels

 

[tooley]

i have been told you can sort it by talking the rocker off and removing the valve rocker thingies (im sorry i really have forgot what they are called!! im quite ashamed of my self since im a design engineer for aston martin.) I think they are called the valve rockers they are hydraulic and use the oil but apparently sometimes the oil dosenot go back in and thats what causes some vvt rattle.

Apparently you need to compress them and dip them in oil and decompress them.I have not tried this so i cant say if it works or not

found this but not sure if it helps they are the other side of the valave rocker arms.

 

[AllanOrr]

some man :thumbs: a have txted my mate so tomorrow in work will get onto the guys in nissan with a shopping list, just want to get it running perfect before going mad and speaning loads on performance mods

 

[pyro3113]

i have a similar issue with mine. i'm pretty certain it's the release bearing though but haven't had the time or money to buy a new clutch (may as well do it all one time) and get it changed yet...

 

[AllanOrr]

thats the thing i aparently had 3 months warranty with the car when i got it at the begining of September so i dont know if i should pull the garage up about it or not

 

[sx-si]

pull them up its not goiung to cost anything

 

[AllanOrr]

true mate am not one for making a hastle about things but its making me rather nervous to say the least if its going to open a can of worms and find out other things arent running right