Hallo all,

 

thanks to Eric / Danny and the Conzult at Billing I now know I need to replace the knock sensor and the two O2 sensors. B*gger. :cry:

 

I take it the O2 sensors are the same thing as wot the manual calls Exhaust gas sensor (EF & EC-16).

 

I have found the immensely helpful basic procedure for plenum removal here http://www.300zx.co.uk/forums/showthread.php?t=30838 thanks to the immensely helpful andyduff.

 

1) I did the pcv valves and hoses last year - do you think I'll get away without redoing them now?

 

2) If so, from andyduff's list, I need

turbo bypass kit

upper-lower intake gasket

throttle body gasket x 2

IACV gasket

EGR gasket x 2

 

3) Is there anything else I should be doing at the same time while we're fiddling about down there?

 

Like is it a good time to replace coilpack connectors?

 

No mods to the engine.

 

TIA - Gio

Gio,

 

I presume you know that you have to remove the engine to change the detonation sensor?

 

In my opinion you may as well buy an aftermarket det warning system, I believe the RX7 guys have knowledge on these, or relocate the original sensor to the another location?

Nah you don't need to pull the engine to do the det sensor! Just upper and lower intake removal. Upper intake (plenum) is a doddle compared to the rest. Timing belt has to come off as the upper idler pulley is bolted to the lower intake. EGR bolts can be a pain but it is possible. Metal coolant lines that run from the stat housing to the matrix pipes etc have to come off and aren't exactly easy to get to. Metal PCV pipe that runs across the back of the engine is a royal pita too. As always though, with a little bit of patience, it can be done... Don't forget you'll also need the lower intake-head gaskets ;) Since the cambelt also has to come off, could well be worth replacing that at the same time, along with water pump, tensioner and rubber hoses, maybe even new thermostat too....

 

HTH

 

CheerZ,

 

Andy

Sounds like it might be easier to pull the engine :p

Or the tranny - thats one option I'm investigating ;)

Since the cambelt also has to come off, could well be worth replacing that at the same time, along with water pump, tensioner and rubber hoses, maybe even new thermostat too....

 

HTH

 

CheerZ,

 

Andy

 

Thanks Andy, yep - did all those 12 months ago :(

Such is life (trivia time: famous last words of ?)

 

I did read that dropping the gearbox would give access if you had small hands but forget on which website I found it.

 

TopLess, there is a suggested place to relocate which is the back two bolts in the middle (H LeHir, I believe) but as I think has been said here, the best possible location for the knock sensor to detect is where Mr Nissan's engineers put it in the first place ;)

 

Cheers - Gio

Gio, this site maybe?

 

http://www.twinturbo.net/net/viewmsg.aspx?forum=technical&msg_id=718589

 

-Andrew

TBH I'd relocate it unless you need to take the plenum off anyway.

It's a lot of work to change something that's not really all that useful anyway.

Thats right it only works at below 3-3500rpm.

Heated debate time LOL

 

IMO the det sensor (although limitted) does have its uses! Get a bad batch of fuel and the car will pick the detonation up before 3k rpm, put the car into safety boost and stop you from blowing the engine to pieces. If its detting that low, then once you get on boost you got problems...

I think it is all a question of balance, yeah sure it will pick up a bad batch of fuel causing your car to det. But you have to weigh that up against not detecting it by ear and the probability of it happening in the first place, versus resiting the det sensor or the profound cost of replacing it in it's original position!

 

It's up to Gio, but my bet is he likes things the way Nissan done em, so he will go the whole hog, but he has got the silver indicators so who knows :D

I also think (controversial :D) that relocating it to the head may actually cause a bit of false triggering. Its more likely to pick up noise from the valve train etc and assume that its det, whereas in the bottom of the V valve train noise would be minimal...

Gio,

Bearing in mind that your car is standard boost etc etc etc, that is why I suggested you didn't bother with the knock sensor - it's just too much trouble to change it. Get the O2's done (which is relatively quick and easy) then save the knock sensor for when you HAVE to do something else in that area.

The red area is where it checks for det.

 

It's up to Gio, but my bet is he likes things the way Nissan done em, so he will go the whole hog, but he has got the silver indicators so who knows :D

 

LOL yes I like to have other people play guinea pig for strange new things!

 

Thanks to all for the advice - I hadn't noticed all the recent posts thanks to Tony and his new firewall in the office. I am now having it reprogrammed with a very large axe. :D

I also think (controversial :D) that relocating it to the head may actually cause a bit of false triggering. Its more likely to pick up noise from the valve train etc and assume that its det, whereas in the bottom of the V valve train noise would be minimal...

 

i agree, if you are going to change it then fit it in the intended place. i dont think that it would pickup other noises such as valvetrain as it is quite specific of the frequency of sound that triggers it. it may however just not pick it up at all.

 

more importantly, make sure it is done up to the correct torque, as this most definatley affects the frequency that it detects ;)

more importantly, make sure it is done up to the correct torque, as this most definatley affects the frequency that it detects ;)

 

Good point - possibly because it is a piezo element? I shall go delve for the torque setting (unless you know it off by heart hint hint :D )

 

Ta muchly

Good point - possibly because it is a piezo element? I shall go delve for the torque setting (unless you know it off by heart hint hint :D )

 

Ta muchly

 

thats right Gio.

 

torque setting according to Autodata is 21-26Nm

Thanks Paul, I spent half an hour squinting at my pdf manual and couldn't find the figure. Cheers

IMO the det sensor (although limitted) does have its uses! Get a bad batch of fuel and the car will pick the detonation up before 3k rpm, put the car into safety boost and stop you from blowing the engine to pieces.

 

 

Is this still true if you have disconnected your stock boost solenoids ?.

I mean can the ECU still put you into safety boost if you have an aftermarket boost controller and have disconnected the stock boost solenoids ?

Is this still true if you have disconnected your stock boost solenoids ?.

I mean can the ECU still put you into safety boost if you have an aftermarket boost controller and have disconnected the stock boost solenoids ?

 

no, but as long as youve got a chip with knock maps, it will at least retard the timing.

 

take that boost controller off & get some boost jets! :D

Gio,

 

You could bypass the throttle bodies while you have the plenum off, blank off the egr system, remove the prvr system, amongst other ideas.

Gio,

 

You could bypass the throttle bodies while you have the plenum off, blank off the egr system, remove the prvr system, amongst other ideas.

 

Hallo matey - probably not if I want to keep my Captain Stock status! (I am waiting for everyone else to mod theirs so I end up with the only stock 300ZX on the planet and then it will rocket in value hahaha cunning plan.)

 

But just for others who may be wandering what all this is about, what are the pros / cons on doing those things?

PRVR often malfuntions causing your engine to run lean and bang!

 

Throttle body bypass, there is a heating system in the plenum to stop the TB's freezing shut if you live in places like Alaska, it defeats the object of having your Intercoolers because it increases the intake temps, also if you bypass this it will vastly simplify plenum removal!

 

EGR removal, for emmisions control and also lowering combustion temps, this bit of kit often malfunctions and has no viable performance gain!

PRVR often malfuntions causing your engine to run lean and bang!

 

Throttle body bypass, there is a heating system in the plenum to stop the TB's freezing shut if you live in places like Alaska, it defeats the object of having your Intercoolers because it increases the intake temps, also if you bypass this it will vastly simplify plenum removal!

 

EGR removal, for emmisions control and also lowering combustion temps, this bit of kit often malfunctions and has no viable performance gain!

 

Sorry to raise this old buzzard but I have a few questions before I refit my plenum.

 

Me and SPinsky made some blacnking plates for where the EGR tubes enter the plenum only to find that you cant really remove the EGR system with the engine in the car, as the EGR pipes that go to the manifold are a b'stard to get to. Is this right? Just checking.....

 

Also, Whats the PRVR system?

 

And this bypassing the TB system(Or should this be Turbo bypass? Help, confused?? :confused: ), does anyone have a diagram of what I am missing out and connecting to what? I would like to do this but I dont want to fVck it up.....

 

Help please oh knowledgeable ones...... :bow: Plenum goes back on this weekend....

 

Oh, one last question, my Manual conversion kit arrives a week on wednesday, is this easier to fit with the plenum off? :duffer: :)

Sorry to raise this old buzzard but I have a few questions before I refit my plenum.

 

Me and SPinsky made some blacnking plates for where the EGR tubes enter the plenum only to find that you cant really remove the EGR system with the engine in the car, as the EGR pipes that go to the manifold are a b'stard to get to. Is this right? Just checking.....

 

Also, Whats the PRVR system?

 

And this bypassing the TB system(Or should this be Turbo bypass? Help, confused?? :confused: ), does anyone have a diagram of what I am missing out and connecting to what? I would like to do this but I dont want to fVck it up.....

 

Help please oh knowledgeable ones...... :bow: Plenum goes back on this weekend....

 

Oh, one last question, my Manual conversion kit arrives a week on wednesday, is this easier to fit with the plenum off? :duffer: :)

 

Hello matey,

 

Ask on TTnet to see if anyone has removed the egr in situ, I have not heard of it being done.

 

The PRVR adjusts fuel pressure according to the fuel temp, it quite often malfunctions and can make you engine run lean and go bang :slap:

 

 

The turbo bypass removes the heating to the throttle bodies and the plenum, to avoid the throttle bodies freezing open when V cold, pretty redundant when you consider all the dough we spend on cooling the charge air, there are several write ups on how to do it on ttnet.

 

 

I don't think it would make too much of a difference doing the man conv with the plenum in place, but it is always nice to have more room.