Firstly hello :) little background

 

Bought my UK 300zx TT on ebay a little while back, with no MOT, so i figured it would need some work.

 

I had the pan welded up, brake lights fixed new horn installed. Failed MOT on brake lines.

 

Had new copper brake lines put in throughout, and the fuel tank and straps replaced.

 

Got the car through its mot has a nice full 12 months HUZAHH

 

 

okay so the current issue

 

until recently its been running fine, now i know the dash board dials are not the most reliable things on the planet but the oil pressure sat steady between 45-60 ish (when warm), but just recently at idle and low speeds we are talking drops to 15psi then raising to 60psi as i get moving.

 

also the turbo pressure gauge isn't returning all the way to -14 (my boost controller is showing -41 to --50 where im sure it used to read -58 at idle)

 

Ive also spotted under the front of the car approx between the middle of the front wheels, the end of a pipe thats cable tied there, no idea what its doing.

 

Now ive pulled the turbo hoses off and the inlets are all clear, there's no dirt or oil from possible turbo bearing leak and my exhaust is clear no blue smoke or anything worrying.

 

anyone A. know what that pipe should be attached to if anything, its under the car. shrug. and B. know what may be cause of the sudden change in the cars oil pressure and turbo pressure behavior (and if indeed its linked to this mysterious pipe), im parked on a cobbled hill so cant really jack up for a better look in the current position.

 

Some pictures below (i know you all love photos)

 

 

 

The pipe is part of the AIV system, you probably have an aftermarket exhaust and no place to plumb them back into the AIV system. A lot of people delete the AIV system anyway so you might want to do this. I believe it should be closed off though not left open, so it could be a cause for a possible boost leak. This could explain the problem with your boost gauge. Also it would be advisable to do a boost leak test to make sure you have no leaks any where else. If you search on google or this forum you can get detailed info on the AIV system and how to do a boost leak test.

 

With regards to the gauges i would advise fitting aftermarket ones as the original ones are not accurate at all.

 

Well done for getting her back on the road looks like a really nice Zed.

 

Regards

Paul

AIV delete............

 

http://s95014253.onlinehome.us/63104/137858.html?*session*id*key*=*session*id*val*

Hello Poodle, welcome to the club :)

 

The pipe hanging down looks to be your AIV, it would have connected to the stock cats. There should be one on each side. I would say that the AIV has been deleted at some point and the pipe has been left hanging. It shouldn't be causing you any problems. If you want to remove it completely; the other end of the pipe connects to a filter box behind the wings (one each side) just unbolt and remove. It's a very common delete. Check here for full instructions on how to get rid ; http://s95014253.onlinehome.us/63104/137858.html?*session*id*key*=*session*id*val*

 

As for the oil pressure, it could well be that the stock pressure sender is on it's way out. It's a common problem. I would recommend that you get separate gauges for both Oil pressure and turbo boost for piece of mind.

 

HTH

 

EDIT: doh, far to slow...

thanks for the info guys its greatly appreciated, ill certaily look at removing the AIV and get some guages ordered up. its a never ending list of things to do. eesh :)

thanks for the info guys its greatly appreciated, ill certaily look at removing the AIV and get some guages ordered up. its a never ending list of things to do. eesh :)

 

That's why we all love the zed mate. :lol:

i need to find some local owners (preferably ones with a boost tester :P )

that AIV line taps into the same vac line as the boost sensor apparently according to that removal guide. which may explain a thing or two about the drop in pressure . the line is dangling under the car, if it was capped off then the cap may have been knocked off, it needs re capping and securing correctly.

that AIV line taps into the same vac line as the boost sensor apparently according to that removal guide. which may explain a thing or two about the drop in pressure . the line is dangling under the car, if it was capped off then the cap may have been knocked off, it needs re capping and securing correctly.

 

Yes it does connect to the boost sensor via a T piece to the boost sender and the AIV solenoid. The safest way to ensure that it's not causing a boost leak is to delete it fully from the vac line. Another common leak problem is the pipe going to the underside of the boost sender. It becomes brittle with age and can split underneath the sender. It's worth checking that it's still in one piece and doesn't have a split in it.

also while im at it, on the left hand side of the engine bay where the manifold starts, there is a two pin electrical connector, its not connected to anything, futther down behind the pipes appears to be its counter part, anyone know what this is or why its not connected. (sorry dont have a photo at this time)

also while im at it, on the left hand side of the engine bay where the manifold starts, there is a two pin electrical connector, its not connected to anything, futther down behind the pipes appears to be its counter part, anyone know what this is or why its not connected. (sorry dont have a photo at this time)

 

Not sure, it could be a few things. If you can get a photo that would help a great deal.

ill try and snap one when i get home later on :) the cars sat at home

i need to find some local owners (preferably ones with a boost tester :P )

 

Where you from?

Im from Skipton (n. yorks / w yorks / lancs border) gateway to the yorkshire dales :)

okay while im at it.... my speedo doesnt work... well thats a lie, it doesnt work for about 15-20 mins then just suddenly starts working and shows correct speed.

okay while im at it.... my speedo doesnt work... well thats a lie, it doesnt work for about 15-20 mins then just suddenly starts working and shows correct speed.

 

Thats a dry solder joint on the back of the clocks. There is a post somewhere with the details of which joint it is most likely to be but i cant remember of the top of my head.

would a dry joint stop it working completely for 20 mins? i can imagine that would stop it working at all, or indeed only work at high speeds as indicated in my readings, but in this case it doesnt work at all for about 20 mins then works fine through all speeds until the end of my journey.

here are the images of those electrical connectors i mentioned earlier.

 

First the upper connector, these are on the passenger side btw.

 

 

then much lower down but not far away is this one

 

sorry this should have been first pic

 

Look like the boost solenoid connectors. Could be wrong though. Do you have a boost controller fitted?

you guys like photos right :)

 

Firstly what i think is my AIV stuff, lots of pipes there :)

 

At IDLE (just started up)

 

At IDLE (warmed up after 10 mins, just starting to warm really)

 

of course it doesnt look too bad like that, but the oil pressure does drop to about 15 when warm (and it didnt before) and the turbo pressure needle never appears to get to the bottom (again it did last week im sure) ;P

Look like the boost solenoid connectors. Could be wrong though. Do you have a boost controller fitted?

 

That's what I'm thinking too....

yeah i have one fitted

yeah i have one fitted

 

Then they are just left disconnected after the install as they are not needed. You can remove the solenoid if you want (i did) but the other connector (top one) just stays there hanging about forever.

guess im gonna have to do a leak test..... *ponders*