My understanding is that it is NOT legal to alter the emission control for any vehicle, the 300ZX couldn't get past EPA with its emissions, so they added in a few things, AIV/EGR, to get it to pass. That isn't to say that the emissions WOULDN'T pass, but if the person testing it knew where they were looking you would cop it for having tampered with the emission controls put in place by the manufacturer. It's written on a plate, somewhere in the engine bay from memory, that the VG30DE/TT engines require an AIV/EGR/Something else in place. You're not, legally, allowed to remove these.
what about the fact the later models z32's didn't have the AIV and ERG systems?. This is what doesn't make sense to me saying you have to have these emissions installed when nissan removed it from our cars later on. If i was to swap the engine sticker to a later one that doesn't list any of the early model emissions parts would you still get done for not having it. Also when do people need to get an EPA test done on a car? isn't it only when a cop pulls you over on a random night and checks the car and slaps on a yellow sticker or something because if thats the case then all you need to do is not get pulled over by the cops or not mod your car to get the attention of the cops.
EGR wasn't removed according to 90TTZ or Pex (can't remember ) AIV's were definitely removed on the Series 2 Zeds. Whether or not it was removed in later models is not relevant as it was originally fitted to YOUR Zed. Unless you have a later model engine installed you have to have it. Stupid, but thems the breaks.
As ive said im looking to it right now and from all reports the 98+ VG30 differently didn't have EGR's but again all hearsay. It is silly. Still the biggest problem i've got with removing the EGR is the talk about engine pinging which im worried about. So thats why im researching it more to find out which models kept/lost and what Nissan did to the engine if the EGR was indeed removed from the factory z32.
There's a ton of information around about egr's and what they do. If i had known what I know now, I would have left mine in place, instead I listened to others who have since retracted or at least back peddled away from there initial reason for deleting it in the first place. The EGR valve, or Exhaust Gas Recirculation valve, is a vacuum controlled valve which allows a specific amount of your exhaust back into the intake manifold. The exhaust mixes with the intake air and actually cools the combustion process. Cooler is always better inside your engine. The exhaust your EGR valve recirculates also prevents the formation of Nitrogen related gases. These are referred to as NOX emissions, and are a common cause for failing emissions testing.
98+ was never exported either. Emmissions laws in Japan (although usually stricter than ours) maybe so that an asbent EGR maybe permitted, although I seriously doubt it.
Its why i haven't removed my EGR yet and don't know if i ever will because it's probably to big of a job for minimal benefit
I'm keeping mine... It also helps with cruising speed fuel economy. And Karl, '94 to '96 were exported to the US and Aus. Some bloke in Melbourne has a '95 TT (J3T SPD??), maybe he can have a look at his.
Just read the wiki on EGR : Id be very interested in how the EGR is controlled and when it comes on and off. Anyone know ?
It's controlled by the ecu, the valve is closed when the engine is idling, at high rpm, starting, when the engine is cold, or very hot.
Thanks for that, although we dont have specifics, (still interested if any one knows the exact operation thresholds), is it reasonable to say that the fear of pinging is usually at higher revs and since the EGR doesn't operate at "high" revs that its removal isn't a concern from this aspect ? Probably a bit broad with out more specifics on how the EGR is controlled.
Um question When getting aftermarket dumps etc for the TT is there anyways to even keep the EGR, since I've not heard of one, (correct me if I'm wrong) aftermarket headers keeping a spot for the EGR?
Not sure if you are actually correct here. Where did you get the quote about exhaust gasses ( approx 350 Deg c) cooling the intake air? Quick read (and it's not very comprehensive) of the service manual states that it is controled by ECU via EGR solenoid and vacuum from the intake. Doesn't say when it operates, but logic dictates (TT) that it would not operate during possitive boost ( intake pressure would escape into the exhaust), or at idle, so that really only leaves during over-run, ( high vacuum and no requirement for power, no load, ) so still cant see how an emission check would pick up the fact that it wasnt there
Everyone, please have a good read of this thread on TT.net. It has all the technical info some of you are chasing and lots of replies regarding how these engines without the EGR still comply in some of the most stringent emissions testing in the US today.
