'98 4Runner Limited 2400 v6/auto/4wd 198k miles. Failed smog. Suspect egr valve. Books say it's under intake plenum cover. How do I remove the ^&*#^*&@(#^ plenum cover to get at the EGR to clean, regasket and replace?

Thanks!

 

egr ? WAT

 

Ummmm..... 3rd gen 4runners never had EGR... atleast my 97 and my 99 dont....
My 99' failed e-test, i replaced the front oxygen sensor (was original with 200,000 miles on it) and it passed with flying colours.

 

What "books" are you using? Look here for the free online FSMs: http://www.ttora.com/forum/showthread.php?t=59089

Is the ECU throwing any codes? That would be a good starting place. BTW you have a 3.4L engine or 3400cc.

 

Early T-100's (pre-OBDII, I think) with the 3.4L V6 had the EGR. That's what those silly little tubes to nowhere on top of the TB are for. He probably has the Haynes manual that also covers those trucks. 3G 4Runners (at least US & Canada) are all OBDII and do not have EGR's.

 

also, if you check fleabay or anywhere cheesy online, you can search
for '1998 4runner egr' and certainly find a lot of places who will sell you one

so, to locate the egr in the vehicle, it is right to the left
of the blinker fluid reservoir
-----
all you have to worry about is

an exhaust header, collector, pipe, bank 1 sensor 1 a/f or o2 sensor, 1 cat , a second cat, bank 1 sensor 2 o2 sensor and a muffler

and the evap system


you need to get the exact obd-ii code if it has one, or the exact gas analysis on why it failed emissions
testing...and then diagnose this without any egr in the troubleshooting steps

 

Good luck with a '98 A/F sensor or second cat, that's as hard as an EGR. (Both started in '99.)

I agree with last sentence. OP needs help with the diagnosis here.

 

Exhaust Gas Recirculation valve that routes a small amount of exhaust gas back to the combustion chamber to cool it enough so that fewer nox gases go out the tailpipe. When they get clogged, the nox goes up and causes vehicle to fail smog (anyway here in CA). Expensive to replace and usually all you need to do is clean it. But getting to the damn thing is a bit of a puzzle for me!

 

Mountain Goat,

Good grief, of course I have the 3.4L! And I was looking right at it when I wrote that. Brain dead.

Thanks for the tip on the web site. No the ecu isn't throwing any codes nor are there any lights on the dash. I'm thinking egr only because I failed badly on nox and I think reducing nox is what the egr is for. Could it also be the O2 sensor?

 

Yep it is, but its kind of an outdated technology not used anymore that I know of on newer vehicles.

So do you get a CEL when you first startup your engine? If, not maybe the bulb is out. I'd try scanning the ECU for codes if that's the case.

 

I know what an egr is

I meant shock and surprise because there isn't one. on that vehicle.

so I say again. You are looking for WAT ? check near the blinker fluid
tank as I suggested earlier

"But getting to the damn thing is a bit of a puzzle for me!"

puzzling indeed

 

Did you even read my post?
WTF is the point of me replying to ˟˟˟˟˟ noobs?

 

Did you want a medal? Maybe he didn't see it. Maybe if you pointed it out to him nicely, he would fulfill your need for a pat on the back.

 

Nah, i'm just tired of giving people concrete answers and them still playing the ignorant card.
Don't need no f 'en medal.
I told him he doesn't have EGR, and that a new O2 fixed my emissions problems, yet he goes to explain to BigBalls like he doesnt know what EGR is. i think i was pretty "nice".

Again churchill, change your o2 sensor, buy it from urdusa.com (cheapest and fast shipping) and see how it goes. If that isn't it, then go CAT... but mine was fine....

 

Old post but just in case anybody with a 3.4L with VVT fails nox

 

I'd bet on it being either your O2 sensor or your Cat. Since the O2 sensor is a basic maintenance item and is not expensive I would start there. It's not hard to do but I would soak the nuts in some penetrating oil a couple days in advance because they tend to give a lot of folks trouble removing them without rounding them off. I can't remember but I think the CA models may have two O2 sensors. One upstream of the cat and one downstream. I own a 1st gen and a 3rd gen 4Runner and I know that's the case for one of them. Anyway, If yours has two, I would start with the one upstream of the cat. I believe it has more more influence on your engine performance and emissions. Somebody correct me here if I'm wrong on that. An old dirty sensor will give you trouble like your having without ever causing an electrical fault and thus no check engine light.

 

3rd gen 4Runners all have two exhaust sensors, one before the cat or cats and one after. '95-'00 Federal have two O2 sensors and one cat. '99 and '00 Cali's and all '01 and '02s have a wideband A/F sensor in front and an O2 sensor in back and two cats.

They do NOT have VVT at all.

It's a five year old thread. Let it rest in peace instead of tacking on misinformation (directed more at the post above yours.)