TheSamba.com :: View topic - Failed emissions...used SEARCH...looking for ideas

Mon Sep 08, 2008 3:27 pm

Hi all. I have read other travails about failing emissions and joined the club recently after my 86 weekender failed. The main problem area was Hydrocarbons...3700ppm when the limit is 220ppm :shock: . Also the CO was something like 1.7% when it is allowed 1%. When the van was tested it was warm but had a really bad loping idle that makes me think it is running rich...apparently the sniffer thinks it is too :) The idle would vascilate between probably 500 and 800 rpm (no tach in the van) during the test...this is saddly normal for my van. I searched the posts and read through my bentley and have learned a ton. I actually have been getting decent gas mileage out of the van...about 20 on the fwy with camping gear. The van runs great most the time...but apparently I am not doing the environment any favors. So here is what I have done:

1. I fixed the TPS. It was not working at all...now it works.
2. I then looked into the Idle stabilizer. It was not working. It test ok per the bently and my ohm meter...however, the signal from the ISCU did not.
3. I determined the ICSU is bad. Unplugged it and took the cover off. Smells of burnt electronics and I can see where some of the track look burnt on the curcuit board.
4. I also tried plugging and unplugging the OX sensor...no changes.
5. I turned the idle adjustment screw out to raise the idle. Now it idles smoothly at aprox 1200 rpm (again by ear)

Questions:
1. Is it possible to pass emissions without an idle stabilizer? I checked the wrecking yards and no one has one used...local parts house was 260 for a new one. I'd prefer to put money else where.
2. Will retarding the timing help bring the HC's down? If so would I want the hatch mark on the crank to the left or right of the parting line? (I was thinking left but thought I should double check)
3. One poster mentioned turning out the screw on the AFM 1/4 to 1/2 a turn to bring down the CO but that this would adversly effect the HC's...should I try it anyway?
4. Aside from my continued searching for vacuum leaks, any ideas???
5. I bought the van in an area where smog is not required...so I am guessing none of the smog stuff has been dealt with in years...which makes my bank account sad...

Thanks.

Mon Sep 08, 2008 4:32 pm

I just tested the AFM per bently and it checked out. I then found that the adjuster screw was 9 turns out from being bottomed. As I turned the screw in the engine idled much smoother. From other posts it sounds like the further out the screw, the leaner the mixture at idle...which is the only level that is tested here in Portland. I think I will leave the screw at the setting that is the leanest yet still achieves a smooth idle. On my van that is about 5.5 turns out from the bottom. Does this sound about right? Is there any way to figure out the setting without a gas analyzer?

Tue Sep 09, 2008 2:17 am

the sad news is the bosch inj is sensitive and ridged at the same time.but if its in good working order you would not be here... :lol: :lol:

the idle stablizer can be bought used on e bay or the classifieds here they range about $50.00 on both sites

the o2 sensor shoud be changed if you fail emissons.but be forewarned some of the o2 sensors might not work even new,i went thru 2 sensors before i had one that was working.you might need to replaace the cat converter if it don't come out.

you want the idle around 900 rpm +/- 50

do NOT over lean the fuel mixture,that will give you a HOT running engine,you realy don't want to burn a valve or a valve seat.

a good shop should be able to do a "pre check" on the emissions,for a small fee.before taking it back for testing.

Tue Sep 09, 2008 10:26 am

I agree with CF.

Your idle air valve system has almost zero to do with emissions.

Your engine needs to be REALLY hot, too, before the test. Drive it like it is stolen before the test and do not let it cool off before the test. A good test shop knows this and you should inform them you want it tested right now, hot.

A new cat works wonders!

If you HC is high and your CO real low, your system is out of whack.

You could have a vacuum leak too, of course.

The standard things to categorically replace are the O2 sensor and Sensor II.

Of course, the standard tune up related items and an oil change.

Tue Sep 09, 2008 11:00 am

Thanks guys. I replaced the temp 2 and o2 sensor, have it tuned pretty well and am going to go through the test in a few hours. If I can't make it through this time I will have to hand it over to a shop to get sorted out. The bummer is you pretty much have to always wait inline at the test stations here in Oregon...so if you get it hot it usually is cooled down by your turn. We'll see.

Fri Sep 12, 2008 6:45 pm

Well???? How did it go?

Fri Sep 12, 2008 7:05 pm

Hold on.

Let us look at the whole. The Failed emissions tells many a tale. It is the Simple stuff.

- Blow by in the exhaust system. Look for black scoring and/or put hand near joints. Any puffs from any connection means the O2 sensor is not getting a true read.

- Vacuum leaks. Be good to yourself and the ride you love. If your riding on a PO's work, think again. It is your ride now. learn what these good Folk here preach.

The temp II Sensor and the O2 sensor are just the tip of the Berg.

Fri Sep 12, 2008 7:46 pm

After a new o2 sensor I was still getting poor numbers. I even took it to a shop to get it tuned...got worse numbers than when I tuned it...so I finally sprung for a new cat. This time it passed with 38 ppm HC (limit 220) and 0% CO (how is that possible) and a CO+CO2 mix of 9%. I'm pretty pleased with that :D

Fri Sep 12, 2008 8:16 pm

It means after the tune up all you needed was a new cat. Your cat was bad. Every few years I need a new one too. At under $150 total installed, it is not too bad. Every 3rd or 4th 2 year cycle I seem to need a new one in my gas VWs.

Did they use stainless fasteners so it can be taken apart easy next time?

Sat Sep 13, 2008 8:41 am

Well there's kind of a story about the cat. I bought a direct replacement one from the local VW parts house. When I went to install it I found the old bolts were pretty corroded and stuck. I started to hacksaw the bottom one off and then decided to check to see how much it would cost to have an exhaust shop put a cat on. I found a place that was only 160 dollars which sounded good to me (only ten dollars more than the replacement cat, bolts and gaskets). However, what I didn't realize was the place just chopped out my old one (including one of the flanges and welded in a new generic one. Not as nice as having a bolt in one...but I hate exhaust work so maybe it will be fine in the long run...just means I'll always have to pay someone else to put in a new cat...

Sat Sep 13, 2008 8:53 am

Well.thats one shop to put on your do not go back to list.
The PO had the same thing done on my Westy. When I collected enough dollars to have it totally re-done...I had it redone.
Seems the catalytic converters only last a year or so, so when you need it to be replaced just unbolt a few nuts, attach the new one and re-bolt it in place.

Sat Sep 13, 2008 4:07 pm

Ya here in Cali they do not seem to last or only perform good enough for a few years. Being able to unfasten the bolts easy is a big plus. You can replace the cat in a few minutes with out even lifting the bus up. That is why I went with stainless fasteners this time.

Sat Sep 13, 2008 4:14 pm

What is all this business about a cat only lasting a year? Are the Wasserboxers harder on cats or something? All my other watercooled VW's (Fox, Scirocco) have always passed emissions, and their cats have never been replaced in the 4 years I've owned them.

-Rob

Sat Sep 13, 2008 5:52 pm

Robw_z wrote: What is all this business about a cat only lasting a year? Are the Wasserboxers harder on cats or something? All my other watercooled VW's (Fox, Scirocco) have always passed emissions, and their cats have never been replaced in the 4 years I've owned them.

-Rob
First I've heard it, too.

My catalytic converter is at LEAST 4 smog tests old. Have another test due this Oct.

We'll see if it gets to its 9th year.

Sat Sep 13, 2008 6:41 pm

What brand cats is youz guyz uzing. I get about twotests worth out of a Bosal..
My muffler is an Ansa and its good for about the same legnth of time.
Adding additives to the oil to take the place of zinc and phosphorous which are now down to allmost nothing can burn out the cats quite quickly.

Sat Sep 13, 2008 9:12 pm

RCB wrote: What brand cats is youz guyz uzing. I get about twotests worth out of a Bosal..
My muffler is an Ansa and its good for about the same legnth of time.
Adding additives to the oil to take the place of zinc and phosphorous which are now down to allmost nothing can burn out the cats quite quickly.
Whatever the brand of the day is when I order. I have gotten the cats from $108 to $125.

Ansa mufflers are cheaply made, I think. My stock muffler has been on through several cats it seems.

We have hydro lifters and our cams are mild, no need for any extra ZDDP.

Wed Sep 17, 2008 10:18 am

I'm currently in the same situation that losith just went through. I have a van with exceedingly high hydrocarbons (2200) and high CO (3-7%) trying to pass an emissions test in Oregon. I've been taking it to one shop that has so far changed the plugs and put in a new air flow meter (purchased from this site, thanks very much). They are currently able to get the HFC down to 400 or so, but that's still too high to pass the test.

Losith's solution is especially interesting to me. My current mechanic says I need a new cat but that it won't affect my HFC test results. Even with my limited mechanical knowledge, that does not seem correct. I also wanted him to change out the oxygen sensor but he said there's no point if I don't replace the cat. Basically, his solution for my passing the test is just to get the van good and hot before going.

I'm hoping some of the experts on this board can offer some suggestions here. I'm willing to pay to get the work I need done done, but I need to make sure the work I'm doing is actually going solve the problem, you know?

I forgot to mention the type of van I'm driving; I have an '84 watercooled Vanagon.

Wed Sep 17, 2008 11:22 am

Is it out of line for you two Portlanders to post the name of the VW folks that did the work on your vehicles? Although I live in Central Oregon, I have been & will be in Portland often & for extended stays as I open up a new store (yeah, in these trying economic times)... so is it bad form or what?
later,
Peter

Sat Sep 20, 2008 8:55 am

I've only owned my van for about a year and a half so I haven't been to very many mechanics yet. I wanted a van with a solid engine and transmission first and foremost, and so far, that's paid off. Now if I can just beat my damn emissions problem...

I can give a tentative recommendation to Halsey Automotive for small repairs. Web sites praise them highly based on their experiences with the original owner, but whenever I visited them I only ever saw the two young guys. They're friendly enough, but not too knowledgeable, and the garage is regrettably lacking in diagnostic tools and equipment. But if you need something small done they should be able to help out.

Sat Sep 27, 2008 2:36 pm

I haven't had enough experience with the shops in question to really say much about them. I think they did there best...my cat was just really bad. When I replaced it my HC went to 38 and my CO to 0%. As cheap as I am I am very happy knowing that my van is not a gross poluter now. I would encourage you to put a new OX sensor on...it will make a difference and a new cat. You should be able to get that done by someone else for 300 total or if you do it yourself 200. Just my two cents worth. Good luck and hope to see you around!!