How to pass CA smog????

[coronan]

I havent been a CA resident in a while but SMOG is intense NOW!!!

In NV its just an emissions test. IN CA they do all kinds of extra tests.

Any how my van had very high CO and HCs.

I also failed on ERG modulator not delivering vacuum to the EGR. I see in the manual that there is a filter that needs to be cleaned. and I need to check the VSV or bypass it for my next test.

I will change the air filter and check plugs.

Anything else???


THANKS!!!!

[timsrv]

The HC's and EGR modulation are likely connected. These vans use a BVSV (Bimetal Vacuum Switching Valve) to activate the EGR modulator. This component is also notorious for getting brittle and breaking. When it breaks this creates a vacuum leak AND prevents the EGR system from functioning. Here is a picture of the BVSV:





The next thing you should check is codes. If there are any stored in the ECU these could be important clues.

Things that can cause high CO are:

Dirty air filter
Bad TPS (Throttle Position Sensor)
Bad O2 sensor
Bad ECU temperature sensor
Bad AFM (Air Flow Meter)
A leaky injector



Things that can cause high HC are:

Broken BVSV
Improper ignition timing
Bad distributor cap
Bad rotor
Failing coil
Failing plug wires
Worn out spark plugs
Vacuum leak(s)
Failing catalytic converter
Low compression in 1 or more cylinders

If you get a code for bad TPS or O2 sensor, then I'd replace these and have it tested again. If the van is overdue for a tune-up or an air filter change, then address these things 1st before taking it back for another smog test. Good luck. Tim

[coronan]

I'll come up with a full inspection this week.

This is off the top of my head...
Compression was low last time I checked (110psi). I just made a leakdown tester but haven't used it yet.
Plugs were recently changed. But I do have a misfire around 2000 rpm with no load.
My BVSV is broke, but I bypassed it so the modulator should have vacuum regardless of engine temp.
I run injector cleaner frequently but have never checked the pattern.
TPS was replaced a few years ago.
02 sensors were replaced last year.
Is O2 voltage output an indicator of it runs clean? What voltage should I look for, for best emissions?
MAF was replaced 1 year ago.

[trestlehed]

2 years ago I had my van smogged. It barely passed, the tech said it was running a little rich.
Fast forward to last month. My mechanic buddy Steve, while doing the new head and exhaust manifold
called me and said he couldn't believe that my van passed smog 2 years ago... Because the EGR sensor connector to
the exhaust manifold was broken off.

Anyhow, that's one more thing you can add to your smog trouble-shooting checklist.
Good luck!

[coronan]

Thanks T!
Its cool to see the TVP community migrating over here!

I had somone swap in an 89 engine and body harness for me after an engine fire.
Turns out the O2 sensor is not even plugged in.

What i believe is the receptecal for it is a 2 wire connector; hanging behind the battery. Did the 89 use a heated O2 sensor?
Is this the proper place to find the precat plug? Can i just jumper 1 of the wires for the 02 output?

[coronan]

O2 sensors:
My book lists the 87 o2 sensor harness to be no color assigned.
The 89 harness lists a "sub o2 sensor" to be 1 brown, 1 black.
I couldn't find the primary in the wire diagram.

I have located the "sub " connector behind the battery.

I also located a one wire harness connector in front of the battery (white wire, female connector) I think this is for primary o2 but but my 87 o2 sensor connector is also female.

I suppose the right thing to do is check continuity to the proper pin on the ECU.

[coronan]

I wonder why my EGR modulator gets no vacuum???

While this fixed my vacuum leak at the time it also rendered my EGR disfunctional.

I will run a longer hose so that it is not kinked. This will make the EGR function before the engine is warmed up. And save me a trip to Toyota. (How much does the stealer-ship want for a Thermostatic VSV Tim?)

[timsrv]

Yeah, establish continuity from the ECU pin to the O2 sensor. The O2 sensor is close enough for you to even run a new wire without too much effort. It's been a few years since I purchased a BVSV, but I'm guessing they'll want around $50.

[coronan]

Almost Done. I'll get the rest checked out next week.

The next thing you should check is codes. If there are any stored in the ECU these could be important clues. CEL - Code 5 = O2 sensor open circuit.

Things that can cause high CO are:

Dirty air filter - Cleaned November 2013
Bad TPS (Throttle Position Sensor) - Replaced December 2011 with used, Tested 11-27 Working
Bad O2 sensor -
Bad ECU temperature sensor - Is this on the ECU board???
Bad AFM (Air Flow Meter) - Replaced December 2011
A leaky injector -


Things that can cause high HC are:

Broken BVSV - Bypassed
Improper ignition timing -14* BDC shorted
Bad distributor cap - Looked good no Carbon Nov 2013
Bad rotor - Looked good no Carbon Nov 2013, replaced Feb 2013
Failing coil - Primary = 1.4k ohms Secondary = 9.0k ohms Both with in spec.
Failing plug wires = Replaced Dec 2011
Worn out spark plugs - Plugs color looked good, gap was 0.051, I cleaned and regapped to 0.048 hand have a little more power. I realize this is larger gap than OEM.
Vacuum leak(s) - Checked with carb cleaner and none by ear.
Failing catalytic converter - Cat has blueish color in side and i can see through the honey comb.

[timsrv]

The open circuit on the O2 sensor is reason enough to fail the CO test, so get that worked out & it should solve your CO issue. The ECU is the engine computer (sits behind the the panel nearest to your left shoulder). An ECU can develop issues that lead to high CO, but since we know the O2 circuit is faulty I'd ignore that possibility for now (not likely anyhow). The possibility of a leaky injector is hard to check, and since we already know the O2 is messed up, I would ignore that for now too.

A bypassed BVSV might make the van run a bit rough when cold, but should not affect hot running or have a negative effect on emission testing (just make sure the van is hot & check that vacuum hose to make sure it isn't kinked). As for other possible causes of high HC, your timing isn't terrible, but it should be set to 12 deg BTDC (with the check engine connector jumped). Rechecking timing after the jumper is removed will tell you the electronic advance system is functioning correctly (should jump around 20 deg BTDC). If timing doesn't change, then the TPS could be at fault (not sending the correct idle signal to the ECU). With the TPS, adjustment is critical (a new TPS that's not adjusted correctly is no better than a bad TPS). If you don't know last time spark plugs were changed, then replace them. I prefer the Denso triple platinum plugs as these are OEM and are supposed to last 60k miles.

Cats fail due to being clogged up (running extended periods with open O2 sensor circuits can cause this ). Internal damage such as broken ceramic mesh can also prevent the cat from doing it's job (but not as bad as having a clogged cat). One more thing to consider in the "vacuum leak" category is mixed up or improperly routed vacuum hoses. Check the vacuum hose schematic and verify they are going to the correct ports. Having high HC's due to low compression is not very common. Not much you can do about it anyhow (short of a full rebuild), so unless it's bad enough to make the van run rough, I'd probably ignore that and concentrate on the things you can fix. It sounds like you're well on your way to completing the list & I'm guessing it will pass once you're done. Good luck. Tim

Edit: The above information on timing only refers to 86 - 89 Toyota vans. For 84 - 85 vans, please refer to post #34 (this thread).

[coronan]

Thanks Tim,
Smog Tests are expensive. I only want to do this once more.

Regarding the high HC:
The only thing I changed is the BVSV which powers the EGR. Hopefully This is enough.

Regarding High CO:
If i remember right O2 sensors are only $20. I may throw one at it for piece of mind.
I knew i was running in open loop; and hoped i was getting some needed extra power out of a richer mixture. I'm aware running old gas will foul the sensor. I'll check the voltage coming out of it.

I'm curious to see the spray pattern on the injectors after so many miles. I already have a jig made up to push injector cleaner through the injectors. This guy did a pretty good write up....
http://www.youtube.com/watch?v=dp-ECEpN52k

[timsrv]

Thanks Tim,
Smog Tests are expensive. I only want to do this once more.............

CA must be quite different than WA. Here (in areas that require the test), the initial fee is $15 with 1 free retest (must be done within 365 days of 1st test). If it fails the 2nd test you can get a waver. Here's a copy/paste from the DMV.org website:

If your vehicle fails its emissions inspection, you will be required to have the vehicle repaired to bring it into compliance. However, there's a limit to how much money you have to spend on this. If you've spent more than $150 on repairs and you car still fails a retest, you might be eligible for a repair waiver.


FWIW, not only does a richer mixture make your engine run dirty, it also kills fuel economy and performance. Over time it will also kill your catalytic converter. In short, there is no good that comes from a bad O2 sensor.......except maybe avoiding the initial expense and hassle of getting it fixed, but in the end it will cost you more. Tim

PS: Testing injectors isn't too difficult. It's removing them from the van that sucks. If you go to that much trouble you should take them to a professional for cleaning/testing. Most places will charge around $80 for all 4. The other way is replacing with new, but I'd still want to have them tested to verify performance before installation. Tim

[coronan]

Wow.
Major power loss after hooking up the O2, reset the ECU and cleaning the egr modulator.
There was a noticeable change of the exhaust when the egr was hooked up. Unhooking It brought some power back but not all.

[timsrv]

[Burntboot]

Did they swap in the computer from the 89, when they did the harness/engine repairs?
How much of the harness was replaced?

[skibum]

I went in for a smog test and had really high hydrocarbons. Turned out my catalytic converter was hollow. I had a new cat (California spec) installed and went back and had no hydrocarbons. I had it installed in Carson City, NV, for a couple hundred bucks. It also helped the "backdraft" fumes that I would get when the windows were down. What Tim said, too, I paid for the first test, but the second one was free. This was in South Lake Tahoe.

Good luck!

[hikersteve]

hey just a note i was having trouble passing smog in ca and figured out that the smog guy was running it as 90's car instead of mid 80's truck.

this gives you about a 20 point cushion on hcs. and 10 on the other so check. some of the guys are pretty so might want to make sure they are running as proper vehicle.

i did do alot of repairs in trying to pass, i had a malfunctioning egr and it was because the port coming off the air chamber(top of the engine) that feeds into egr was clooged. Had to remove and have cleaned. you cant poke it out because there is a sharp turn in the port. there is a plug that can be removed to clean out but it faces back of engine compartment so dont know if it is possible to do with air chamber on engine

also did o2 sensors, recomend getting oem, as universals are junk and arent plug n play. they are so bad when i went to get oem from oreilys cause the new ones made my van run terrible the gal that worked there refunded my money for universals, even though i had installed the parts and just threw them away right in front of me.

not sure if anyone brought these points up jst skimmed through thread

hope it helps

[coronan]

I discovered a clogged hard line yesterday too. I tried to clean it with compressed air and carb cleaner, I even let the carb cleaner soak for an hour. It didnt want to budge. I bypassed it with extra rubber hose.

The pressure test on the EGR was very difficult. It's hard to tell if the controller breaths or not even blowing on the hose by mouth.
Does anyone else have experience with this test?

"INSPECTION OF EGR MODULATOR"


I replaced the 02 sensor this morning with a bosch.


Unfornutately when I got tested for smog it was not done by a STAR station. Now the van has been labeled as a "gross poluter" and can only be tested by a star station.

Anyone considered registering their Van as a "CLASSIC VEHICLE"???

[coronan]

According to the manual the EGR modulator applies 3" vacuum at 3500 rpm and high vacuum with the R port hooked strait to the manifold.
Mine does.

But the smog test is run at 2500 rpm. my egr will not be active.

Anyone else see a problem with this.
I'm confused.

[hikersteve]

so the actual port off air chamber was clogged on mine not just a line if. your egr is not workin or failing i would check that.
your post are from reno and your tryin to get smogged in CA??
if your talking about classic car in Ca forget it i dont even think they reached the seventies yet. in washington its 25 yrs then no emissions, but cali has some stupid system to figure out and when i asked at dmv, because i have a 84 carb. sr5 wagon the lady just laughed and said it was like 1967 or older wh ich wasnt any nominal timeframe like 20 25 or 30 years. I will try and get a pic to show you port i am talking about tomorrow