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Hello every1, have a problem,was hoping some1 could help me with,

my zx tt as a rattle/knock what sounds like bottom end,

Its weird cause the sound only happens if i blip throttle around 2500 revs

If i rev it high [6000] theirs no noise at all,

And no noise before 2500,

 

Put it on a ramp today, and from underneath the car it sounds like its coming more from the top end of engine,

 

I change the oil every couple of months at the worse for mobil 10w 40, and dont do many miles,

And its allways around the maximum level {dont use much oil, never needed to top up between oil service] But last few days its been getting a little tappy [lifters] so was gonna change oil, then the rattle/knock came,

So i pulled dip stick out [no bloody oil] no oil light came on, and as i say never used oil before,

No leaks and aint smoking so i be fu@ked if i know where its gone lol,

someones nicked it,

I have topped it back up with oil, noise still their and no leaks or smoke,

 

everytime i sort something on the car theirs something else,

 

auto box went [manual conversion]

turbos went replaced them,

clutch went [replaced]

manual box went [replaced]

misfire [cleaned connectors] replaced ptu,air flow meter,cas, was running perfect for 2days now this lol, and thats without shocks, bushes, and other little bits i have replaced,

 

any help appreciated thank you,

 

sorry for going on, but got to say it somewhere,dont want to mention it to the misses ,i think she will kill me,lol

Featured Replies

Cant really diagnose a noise over the Internet, but around 2500 is the typical rpm to hear a bottom end knock.

 

Bottom end will "usually" give a more hollow Knock, whereas the topend will tap.

  • Author

its weird its more a rattle,

 

i have had a few bottom ends go and they normally lose power and get worse the higher you rev them,

 

i have drove it home from work 10 miles as only car had their and it aint getting no worse,

 

thank you

when blipping the throttle to get the knock, remove a coilpack one by one, replacing after you have removed, if the knocking stops on one of them its prob bottom end

  • Author

its typical my sound dont work for some reason on computer,

as yours gone too lol, sorry to hear if it as,

thank you for trying,

i havent got a zed anymore, but the bottom end did go, sounds like sombody tapping the engine with a hammer

  • Author

see mine is not that loud, its god i wish i could explain things better, but im useless at it lol,

 

it sounds more like when a diesal engine is timed wrong on the pump or starved of fuel,

 

looks like its just gonna have to strip it down,

i have another engine being put together with forged internals and acl bearings,

and have a jap shell which is mint what im having sprayed,[same white as mine]

was gonna put engine in shell,

drive mine to all that is done then nick interior and panels off mine,

so i didnt have to go without a zed or car,

and havnt got the money to do it all at once,

 

looks like i just have to get the bus to its done lol,

 

thanks again,

Unplug the vtc solenoid plugs rev it a few times and see if it goes.That rev range is when the variable timing control works and can make a rattle if the springs are faulty.The vtc solenoid plugs are located at the n/s rear of the plenum,grey 2 pin oval plug and the d/s front of the plenum close to the power steering resovoir,grey 2 pin oval plug also.HTH.

  • Author

i try tomorow mate, didnt think of that, i hope so lol,

 

it does it in neutral and in gear, would it det in neutral reving to 2500rpm it does sound a bit like a load of bearings in a jar,

 

thank you

i thought dett only happened when driving on boost

 

Think you can get dett at any time can`t you? If the combustions not right it`ll just happen till corrected.

  • Author

i try variable timing tomorow,

thank you every1

for your advice

  • Author

tried vtc solinoid still their,

sold my other car so have had to use it for work today drove 30 miles and its no worse,

surely it would have thrown a rod by now,[if bottom end]

oil pressure is as its allways been,

nearly 120 on cold start up, low not far above 0 on idle when warm, and moves up to about 30 when driving,

it starting to make me think cam/lifter fault, if i open the bonnet it does sound like its coming from below where the balance bar is located,

any other car id just rip the rocker cover off, but someones put a great big plenum on top just to annoy me lol,

 

as anyone else had a cam/lifter fault,

 

it sort of chatters away, not like the tap the lifter use to make on start up,

 

thank you every1,

when driving does it sound like its tappety at 2500-3000rpm???

 

i drove mine for weeks like that, take ya time and it will go on for a bit

 

have you tried removing the coilpacks like i suggested

 

my oil pressure was like that

  • Author

i did mate and it didnt seem to go,

its hard to diagnose as their so much on top or underneath where noise comes from

thanks

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