CA smog, help needed

rolling blackout

New member
Failed smog today. High hydrocarbons and high NO.
20131205_092717_zps79c252f0.jpg~original


I checked the temp of the cat and found the inlet at 404ºF and the outlet at 412º. Seems to me I have a bad catalytic converter, just wondering if there's something else I should be looking at?
 
Register to hide this ad
Usually high HC means the oil is old. THis happen to me one time on my 86' Beater. I rarely use it and change the oil maybe once a year.

Change your oil. If not time to change the CAT.
 
Usually high HC means the oil is old. THis happen to me one time on my 86' Beater. I rarely use it and change the oil maybe once a year.

Change your oil. If not time to change the CAT.
If the cc wasn't operating properly, it should trigger an error code, have you checked?
You don't need a scanner, just jump the two terminals and count the CEL flashes.
 
Was the truck hot when they tested it? That helps with borderline ones.

My last CA test was just after replacing the Cat (OEM was stolen). An aftermarket was only $90 or so, and it's just 4 bolts on my 92. But for the test I went at lunch and only drove it a half mile or maybe mile at most. Not the best before a test, and my numbers were much higher than before.

We moved and I don't have to test anymore, but I'm still curious of how the aftermarket $90 cat compares to the Toyota $900 part.
 
I did change the oil before the test and drove it for about 45 min on the way to the test. I just tested the egr valve and it appears to be operating correctly, but I'm not so sure about the egr vsv. The vsv does get a signal to turn on/off but I can't feel any vacum from any of the hoses. Does anyone know what state the vsv should be in without the "on" signal to it? Should it be open, allowing vacuum to flow?
I also just noticed something interesting, even though I live in CA, this 4runner says it has federal emission standards and is not to be sold in CA!
 
If the cc wasn't operating properly, it should trigger an error code, have you checked?You don't need a scanner, just jump the two terminals and count the CEL flashes

No CEL, but I don't think a faulty cat would trigger a code (in my case) because there is not a O2 sensor after the cat.
 
The Fed version shouldn't matter. It's probably the same as the 92 3000gt I messed with, that the CA version does have a few extra emissions things, and the ECU then is a little different to take these things into account. I've seen a few things in my 92 FSM's that are specific to CA (a charcoal canister, etc) and then in the service specs there's a couple things they call our to change or not change on the CA model.

But they are mostly the same. Personally I'd consider dropping in a new aftermarket CAT since it's under $100 and so easy (assuming your's is 4 bolts like mine….at some point they switched to welding it in, but even that wouldn't add too much to have someone install). But that might just get you past this smog test, if it turns out that something upstream is fouling the cat.
 
I tried looking for a bolt in CAT a while back, and they don't make them with flanges unless it's from the dealer. The first CAT I got was from Performance Products, around 1998, before they got bought out by Eklers a few years later. Most people have them welded in since it's pretty easy to un-bolt (steal) them because of the ground clearance.

OP, was your T4R from another state?
 
Emissions & Vacuum

I did change the oil before the test and drove it for about 45 min on the way to the test. I just tested the egr valve and it appears to be operating correctly, but I'm not so sure about the egr vsv. The vsv does get a signal to turn on/off but I can't feel any vacum from any of the hoses. Does anyone know what state the vsv should be in without the "on" signal to it? Should it be open, allowing vacuum to flow?
I also just noticed something interesting, even though I live in CA, this 4runner says it has federal emission standards and is not to be sold in CA!

Yes, the VSV hoses often get mis-routed, especially the three small tubes
just under the passenger side plenom, during a valve cover/plenom removal.
You would have foul smell and poor idle. Located low on pas fender on 3VZE.

First http://personal.utulsa.edu/~nathan-b...74layoutan.pdf
Will help visualy.
The VSV are Blue is PAIR, RED (brown) is for Fuel Pressure up and Green is EGR.


The top of the VSV is from the vacuum source and the secondary goes to the item its running.
EGR vacuum comes from 2 vacuum lines to the modulator then from there to the top of the green VSV, From the bottom of the VSV (bleed off filter) goes to the main EGR valve.
EGR only turns on when a cruise or light throttle is happening.


PAIR, From manifold to a one way valve then to of the Blue VSV top, Out to the PAIR valve.
Only turns on during deceleration.
Fuel pressure up, From Manifold to the Red (brown) to the regulator.
Turns on during acceleration dropping vacuum to zero increasing fuel pressure.
Fuel pressure up can be bypassed if the VSV is bad.

You have to pay special attention to line routeing, the vacuum hoses ARE numbered for your convenience, take your time!
Remove the modulator top cap and clean out the carbon in the internal filter with CRC throttle body cleaner. (located next to EGR)

Bills86e
 
Last edited:
Thanks bills86e, that's a huge help! It does have an odd smell at idle, and is slightly ruff. I'll keep looking at the egr system. I pulled the egr valve off and found a little bit of carbon on it and in the intake manifold.
 
I tried looking for a bolt in CAT a while back, and they don't make them with flanges unless it's from the dealer. The first CAT I got was from Performance Products, around 1998, before they got bought out by Eklers a few years later. Most people have them welded in since it's pretty easy to un-bolt (steal) them because of the ground clearance.

OP, was your T4R from another state?

My 92 4runner is a CA one, but after my cat was stolen I checked under quite a few similar aged 4runners (all likely just a little newer…such as having longer roof rack rails so '93-'95) and I think they were all weld on.

At the time, 7 years ago, I was able to order a bolt on cat just fine. I think it was from sound pro or something like that. I haven't checked on rock auto to see if they still have bolt on ones, and when I had my muffler replaced he just welded it on to the cat….so I don't have a completely bolt-on one anymore. ….but I have a welder now, and I'm slowly getting a little better with it.
 
Good dig N figgering out my mess!
It is NOT a very good picture of the configuration to the metal tubes to EGR-Modulator,
fuel regulator.
I'll try to get the good ones, up date my Url's. Thanks!
 

Members online

Forum statistics

Threads
278,307
Messages
3,554,056
Members
248,016
Latest member
Advally Service

Trending content

Back
Top