finally got my Z back on the road after 3 months! all running sweet when the car is warm but when its cold there is a bit of a ticking noise which i believe to be the manifold.

 

the really nasty noise starts when i start driving. anything between 2k - 3.5k there is a really nasty screeching sound. dosnt sound like a belt slipping and only does it when its moving, in any gear. its quite a loud sound.

 

also the car feels down on power. im used to driving a fiat coupe turbo with 220bhp so i expected a modded 300zx to feel at least sliiightly faster but it just dosnt.

 

it has full decat, 360 degree turbos, jwt chip @ 14psi, blitz induction kit.

 

i havnt been able to get to a rolling road yet but it definatly dosnt feel like 300bhp..let alone anymore the mods would give it.

 

any help would be great,

 

Joe

Somethings is definatly wrong, i had a coupe once too but the zed will kill a standard one.

 

What does your boost gauge read at full throttle?

 

That ticking noise could be a manifold but then again it could be a sticky lifter.

 

You might have a boost leak somewhere.

so would be worth doing a boost leak test if you can.

That screeching noise... maybe a leak? or a noisy turbo? i hope not

at full throttle the boost is just off the scale..but then at idle its not exactly zero. i know these guages are very inaccurate so im not sure what to think.

 

both the ticking and the screeching noise only happen when the engine is cold. once its warmed up everything is fine.

 

it can be very embarrasing driving past people on a cold engine with it screeching away!!

 

also..how good are the standard temprature guages? mine seems to be in the middle most of the time but occasionally, mainly on a motorway, the guage will drop in tempreture, sometimes to zero. im thinking a loose connection but it can make you a bit paranoid!

 

Joe

So it only makes the noise when moving?

yeah only when moving and the engine is cold. once you hear the turbos start to spool up it quietens down and stops. also..when its cold the car hesitates quite a bit before boosting. id never use any real performance when cold...i dont go over 3.5k but it hesitates getting there.

 

Joe

elaborate on the screeching noise?

 

 

here i found this: http://www.300zx.co.uk/forums/showthread.php?t=61461&highlight=screeching+cold

 

Probably a siezed pully somewhere ac pump/alternator etc

common fault which makes a loud screech is the alternator belt slipping when cold

its simple to tighten up , do a search on here , what is your tacho doing ?? does it all of a sudden Rev after a hesitation ,.....i think you have a mix of problems , with the main one being the clutch cant handle the mods youve done and its slipping , and the aletnator belt is slipping at the same time and i would do an ECU diagnostic and check for boost leaks like Jimmy says

 

good luck mate

 

Steve

i agree... and yes the alternator is very easy to tighten up, once you get underneath its very clear.

the screaching sound to me like you have a boost leak and it will get worse if you just leave it, do a leak test as jimmy said.

With the noise as he discribed it, doesnt seem to be a leak as he has full boost and a leak is more of a ssssssssssss noise screech is most prob a belt...... but he said its down on power so its hard to tell without seeing it up close. And im sure the zed is faster than a stock coupe, although mine was rapid running at 1.2 bar. :D

the screeching noise definatly sounds more like a belt than a boost leak but it only happens when its cold orr when the cars been driven round and the parked up for 10 -15 mins. so its had a little bit of time to cool off. il jack it up tomorrow and see if i can tighten the alternator belt.

 

been changing my friends manifold and putting a decat pipe on my friends..ehem *saxo* but it took all day as the new manifold had the worst designed bolts in the world so i had no time to look at the zed.

 

also..the ticking noise..could it be the manifold or something else? again it only does it when its cold. would a sticky tappet not tick all the time?

 

Thanks

 

Joe

Check the water pipes at the front are not leaking a bit onto the belts, this was happening to me once ,making the belts slip at start up and i just had to tighten up the hoses and it was ok.

But check all them belts anyhow.

If they are tight and its still doing it then either the alternator or the aircon pump bearings are siezing.

ok, had a look today but cant find any sign of leaking pipes.

 

ive oiled some of the pulleys and had a good look but cant really find much.

 

also, to add to my problem, the ticking noise has started happening constantly even when warm. the cars starting to sound like a banger! without the noise the engine is quiet and sounds fine.

 

when it went in for a cambelt/waterpump change the mechanic said there was a small crack between the manifold and turbo..could this cause the ticking?

 

cheers

 

Joe

ok, had a look today but cant find any sign of leaking pipes.

 

ive oiled some of the pulleys and had a good look but cant really find much.

 

also, to add to my problem, the ticking noise has started happening constantly even when warm. the cars starting to sound like a banger! without the noise the engine is quiet and sounds fine.

 

when it went in for a cambelt/waterpump change the mechanic said there was a small crack between the manifold and turbo..could this cause the ticking?

 

cheers

 

Joe

 

yep if its a hairline crack in the manifold it would make a ticking noise when cold, but normally disapears when the metal expands unless its goten bigger and making the noise constantly.

yeah the noise used to go away when it was warm but after a bit of..'enthusiastic' driving (not breaking speed limits, just fun) last night its started happening all the time. it gets a bit quieter when its warm but its still there.

 

so is that ******* screeching noise!! i cant think what it can be!!

its so embarrasing driving round with it screeching away!!

 

Joe

anyone?? is it possible to repair the manifold by welding the crack up? or does it mean new manifolds because i really dont have the money now after a £700 cambelt and waterpump change!

 

please recomend someone who might be able to help me!

 

Joe

you probably could weld it..... but getting to the manifold is gunna be a bitch...

argh! i cant afford this!! is it an engine out job? i might have to sell my fiat to finance this car!!

 

Joe

Yep i think it is :(

But hay welcome to the club :)

 

Get a mechanic to check over it again just to be sure it is that.

 

Hay more reason for a uprated rebuild :)

decide whether to keep the 300 or the fiat, both are high maintance cars, Buy a run around and keep one or the other for plessure ):

oh lord! how much do we think that might cost then? i would love to get an uprated rebuild its just im so short on money after the cam belt!!

 

im going to be keeping the 300. im thinking maybe a little run around would be a good idea though...

 

i think all my zed needs is the manifold and this screeching noise sorting out,

 

then theres the problem of it being hesitant under boost while the engines warming up..

 

then the problem of it feeling underpowered..

 

then the petrol smell...

 

and the leaking roof

 

but apart from those small problems its great!

 

(oh and the front bumper scrapes..over everything!!)

 

 

Joe

I did exactly the same thing, i spent 400 quid on a cambelt change only for the engine to start smoking big time a week later, did a compression test and :( wasnt good, so i looked on the bright side and im currently having it rebuilt with a few uprated bits.

 

I think an engine out and in is around £550, but if you decide on this then its best to have the rebuild and get it all done while its out coz if it gives up in a few months time youl be gutted. So you will have to decide what you wanna do.

a stock rebuild including labour is around the 2000 mark.

1300 labour 700 parts,

 

but mate it might not even be your manifold making that noise so just have it properly checked out first.

yeah thats very true.

 

need to speak to a mechanic sharpish then i guess. :( i just want it to work!!

 

thanks for your help j1mmytt..

 

il get it in the garage and let you know what the result is!

 

Joe

ok good luck. I hope its something silly thats wrong :)

just out of curiosity...what would the rebuild involve? which parts would be replaced etc?

 

might have to get myself (another) credit card!

 

Joe

pistons/rings, bearings, all gaskets including head gasket, head skimmed, rebore, crank ground, head work? but do a thorough search on here theres loads of info on rebuilds. it all depends what u wanna do and what needs doing, ul prob wanna have the turbos rebuilt aswell......£££££ sorry :(