EGR Valve

[thejfed]

Hey guys,

We have a 1990 300ZX. Mechanic says the EGR valve isn't working. We've heard two different things. One mechanic is telling us that the EGR valve isn't necessary and we should buy the block-off kit since Minnesota doesn't have emissions. Another mechanic tells the EGR valve is necessary.

Can you provide any insight?

[Ace2cool]

Not necessary. Delete that bish with a quickness.

[thejfed]

Can you explain why it's not necessary? Again, getting conflicting stuff from "mechanics." Sadly have yet to find a true Z mechanic in MN.

Also, I'm told it's a PITA to get to the EGR valve. Something like 9 hours of total labor start to finish. That sound right?

[GerryO]

http://autos.yahoo.com/maintain/repairq ... 080_1.html

EGR valves help make our air cleaner, reduce the risk of detonation, can leak and are an absolute bear to replace.

[thejfed]

Sooo basically if ours isn't working and we are going to do something about it, we should just block it off instead of replacing it. I'm not sure how much I care about clean air with this car considering it gets driven less than 2,000 miles a year.

[Z31toZ32]

how would your mechanic know that it isn't working? is yours a 96 with odbII? I would just leave it as is until you do some sort of maintenance that requires you to pull the plenum. when you do that, then you can do the official "egr delete" which cleans up a crapload of vacuum lines under the plenum and makes your next plenum pull easy.

[A Paratroopers 300zx]

Here is a link with a ton of info on the EGR valve and delete process:

http://s95014253.onlinehome.us/63104/197828.html

Hope this clears things up a bit!

P.S. On an OBD I system (1990-1995 Z32), there isn't really a way of determining if the actual valve is malfunctioning... unless you pull it and inspect it. Very hard to do with the engine still in the car. Over the years, the valve can become gummed up with carbon and stop working... causing all kinds of issues.

[thejfed]

Engine is developing a rough idle. Mechanic determined it's a combination of the 02 sensors being shot and the EGR valve leaking. While he isn't a dedicated Z mechanic, he's pretty good. I trust him.

[thejfed]

After reading that article, I'm even more confident. My mechanic said basically the same thing. He informed me he could do it with just the upper plenum pulled, but it'll be a PITA. But at this point, it's becoming necessary.

[Z31toZ32]

just because you trust him doesn't mean he is making the right call. these cars are tricky... you need to find a z guy.

anyway, if the car is still at the shop, tell him to ohm the injectors. it doesn't take more than 10 minutes. a rough idle is usually caused by an injector or two going out. here is a guide: http://www.twinturbo.net/nissan/300zx/F ... ctors.html

[thejfed]

It's not currently in the shop but it'll be going back.

I know I need a Z guy...but I've yet to find one in MN. If you can help I'm more than open to finding one I can trust that knows these cars. Will have them check the injectors.

[GerryO]

It's not currently in the shop but it'll be going back.

I know I need a Z guy...but I've yet to find one in MN. If you can help I'm more than open to finding one I can trust that knows these cars. Will have them check the injectors.

Print these materials, ask your mechanic to read through them and he'll be that much closer to being a Z guy.

http://home.swipnet.se/e-solutions/Vacuumleak.html

http://www.mdsmarthome.com/z/Z%20Tech/Z ... 20Idle.pdf