Basically im trying to eliminate a rough idle problem my Z has quite a lot when at running temp, I have had to live with this for 6 months now and it is really getting irritating & deffinately embarrasing and id like to solve the problem so im working my way through everything possible that isnt quiet right with my Z, so far i have removed intake pipes and cleaned throttle bodies (throttle jams on occasion, still after cleaning), set the tps to correct setting, set idle as per insructions found here, AIV's have been removed as per TT guide checked air filters (all ok), due for all oil's to be done (next week hopefully), found 1 small fuel leak (cured ages ago). help needed before i get fed up and get rid which i dont wana do coz i love my Z sooo much.

 

The part in question here i think is part of the PRVR system which was removed before i bought it, i dont think it's been done right, Please look advice needed before i give up the Z.

 

P.s thanks in advance & if any of you guys are ever in the plymouth area and wana get together, it'd be cool to see your motors and have a natter a beer iv'e never been to any meets etc before, but im dedicated to my car's, I always have been.

 

This part on the plennum (circled in yellow) on my Z has no pipe on it to connect a hose to, it has a screw in it blocking the hole!!!!! is this ok? it was like this when i got it! could this be causing my idle problem? will i be able to get one from nissan? is it an important part? id like to have piped correct advice needed.

 

what is the other end of this hose connected to? is it the fuel regulator or someting? im not to sure but would like to know..... im trying to cure a rough idle which settles after about 30-45 seconds after coming to a halt, sometimes stalling.

 

 

 

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Have you checked the plenum to manifold bolts for tightness? I spent ages with a mate who also had a shiny plenum- powder coated and after swapping all kinds of bits with mine with no improvement we spotted the plennum was actually loose - maybe some stripped threads with it being off and on again! Sometimes the gasket would seal and all was well and other times rough idling with air being drawn in.

Have you checked the plenum to manifold bolts for tightness? I spent ages with a mate who also had a shiny plenum- powder coated and after swapping all kinds of bits with mine with no improvement we spotted the plennum was actually loose - maybe some stripped threads with it being off and on again! Sometimes the gasket would seal and all was well and other times rough idling with air being drawn in.

 

Sorry if i confused things mate, the pic above is not my motor i borrowed it off smithy's site (hope this is ok!) My plenum is not chromed it is standard, is it poss i could still have this problem though?? how much of a job is it to check/replace plenum gasket?

I think you should take a picture ofyour car so we can see the problem, but if it is the feed to the FPR this could be giving you problems!

I think you should take a picture ofyour car so we can see the problem, but if it is the feed to the FPR this could be giving you problems!

 

Here is a picture of mine, you can see the screw, + the small FPR has a short piece of hose coming from it with a bolt in the end blocking it....

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The hoses to the FPR should not be blocked, send a picture of that as well so we can have a look?

Here are more pictures of the FPR + blocked hose & the part on the plenum with the screw in it!!

 

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As Mark said the hose to the FPR should NEVER be blocked as it's the case with your car.

Get a new plenum connector (the one that now has a screw into it) and connect the FPR hose to it.

As Mark said the hose to the FPR should NEVER be blocked as it's the case with your car.

Get a new plenum connector (the one that now has a screw into it) and connect the FPR hose to it.

 

Right ok then, could this be the cause of the rough idle, which settles after about 30-45 seconds?

 

Is this a nissan part?

Are all the small vacume hoses 4mm? so i can buy some more coz i need to redo my boost gauge lines aswell as new hose for the FPR.

Right ok then, could this be the cause of the rough idle, which settles after about 30-45 seconds?

 

Is this a nissan part?

Are all the small vacume hoses 4mm? so i can buy some more coz i need to redo my boost gauge lines aswell as new hose for the FPR.

 

It is a Nissan part but one of the breakers on here can sort one out for you, and yes get some new hose and redo the boost gauge hose as this will affect your idle as well as the fpr hose, do it asap as incorrect fuelling can damage your engine!

Been down my local Jap garage today,they reakon they have this part in stock second hand somewhere, Nissan wanted £12.61 +vat back order 8 weeks, gotta go back tommorrow for it, My facory boost gauge is all plumbded in fine it's the boost gauge hose for my hks gauge im missing at the moment. cheers guys really appreciate your input, Ill let you know the result once sorted.. Thanks :bow: