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Wed Apr 24, 2013 7:55 pm

the problem is going to be to find someone who understands the AFM as well as what an air cooled VW needs to keep from over heating. Justin is the only one I know who even touches late bays here in town. There are a couple other places but they specialize in early bays. It is a really sensitive adjustment and frankly I only took the time to learn it cause after 3 rebuilt AFM's by the main US rebuilder failed I had no choice but to learn it.

BTW - although Ken at Busco should be able to get you a good used one cheaper. http://www.thesamba.com/vw/classifieds/detail.php?id=1439151

You might read this site and see if it helps: http://www.ratwell.com/technical/Smog.html

Wed Apr 24, 2013 8:29 pm

ivwshane wrote: SGKent wrote: I need to stop this now that I have had dinner and my mind is functioning again. The clamp will not work as it is downstream from the cat. You will have to weld a bung in. That is how it will have to be. If they have a regular tail pipe sniffer you can put some penetrating oil on the cap on the bottom and see if you can get it loose. They can insert the sniffer there and set the idle CO but I don't think that will be enough to solve your issue.

That or get a new exhaust and cat then drop by some weekend or get your own LM-1

I was wondering why one would need access before the cat and the other method didn't.

It sounds like the best option is to take it to a test center and just adjust and re test. I can change it back to pre adjustment settings to keep things safe/rich. And when money gets flowing again I'm just going to upgrade the exhaust and then I might stop by;)

Sgkent knows the AFM inside and out. He is the wizard when it comes to these. Have hime or Colin dial you in for added security.

Fri Apr 26, 2013 3:52 pm

Fuck it! I'm just going to bite the bullet and replace everything:|

I went to the smog only place to try and dial in the AFM and I got it close once but then after adjusting it againt to get closer it got farther off, I then set it back to the previous spot and it was way off again:|

There must be more going on so I'm going to get real intimate with my bus and spend a lot of money and fix this myself with my own tools.

This is one sure fire way to force me to learn.

So on my list of parts this is what I plan on getting, if you see ANYTHING I am forgetting please let me know OR if you think there is a better replacement part/kit I should look at let me know!:

LM2 (I can't find an LM-1 that's any cheaper than an LM-2 brand new)
Exhaust pipe from samba (mine was welded to the CAT)
Emico CAT that is CARB II certified with O2 sensor bung hole (and I believe it comes with the plug)
Vacuum hose kit from German supply (out of stock)
Decel hose from GeeBee
Aux. air regulator to air plenum from GeeBee
Oil breather hose from GeeBee
Valve cover gasket from busdepot (OEM elring/germany)
Fuel line kit (german supply but are sold out)

I also need the correct gaskets for the CAT and pipes, what/where should I get?

I also would like an in dash guage that will fit in the clock location that does RPM and engine oil temp, any recomendations (yes I will search)?

The links below are for me to make it easier to find everything again.

Vacuum hose kit
http://www.germansupply.com/home/customer/product.php?productid=17614
Fuel line kit
http://www.germansupply.com/home/customer/product.php?productid=16400
GeeBee Hose
http://www.thesamba.com/vw/classifieds/detail.php?id=1327089
GeeBee Breather hose and Decel hose
http://www.thesamba.com/vw/classifieds/detail.php?id=1220031
BusDepot valve cover gasket
http://www.busdepot.com/021101481
Emico CAT
http://www.emico-catalytic.com/appchart/product.php?prod=335057
LM-2
http://www.amazon.com/Innovate-Motorsports-3837-Di...ovate+lm-2
Exhaust Y pipe
http://www.busdepot.com/021251531
Hardware Kit from german supply
http://www.germansupply.com/home/customer/product.php?productid=17019
Muffler from Busdepot
http://www.busdepot.com/071251053c
Tail Pipe from Busdepot
http://www.busdepot.com/071251053c
Exhaust gasket kit from german supply
http://www.germansupply.com/home/customer/product.php?productid=18188

Fri Apr 26, 2013 8:04 pm

Welcome to the didn't pass smog so now it time to spend some money club.

You are going down some of the same paths as I did. My high HC at idle was from vacuum leaks, one big one from working on the brake master, and a bad distributor. After I got everything sealed and replaced the distributor it went to high CO. I became exhausted racking my brain with adjustment, second guessing myself, and finally throwing new parts at it.

Mine ultimately turned out to be the heads.

From what I have learned on mine, if you are blowing HC's post cat I going to strongly lean towards a lean misfire. I added a cat in the testing process and fixed my lean misfire condition, that lit off the cat and next test the HC's (lean misfire) were catalyticly converted to high idle CO (rich). My head problems were the cause of needing to run rich at a idle to run decent.

If you GEX stamped into your case don't worry about the exhaust... report in the making on my smog related but completely separate topic.

Fri Apr 26, 2013 8:19 pm

Quote: I went to the smog only place to try and dial in the AFM and I got it close once but then after adjusting it againt to get closer it got farther off, I then set it back to the previous spot and it was way off again:|

I warned you it isn't all that simple unless you have been thru it before. You'd think 2 + 2 = 4 but it doesn't because the AFM sees in 2 planes instead of one. It doesn't think linear like we do. It also measures how fast the door moves which adds a time component to it as well - and it measures air temperature coming into it so when it sits and heats up that changes things too. Think of it like a batter trying to hit a ball that can be pitched from in front of him, from behind him, or off to either side and at any speed.

When you get the bung welded in that will take a O2 sensor and a cigarette lighter socket let me know.

Fri Apr 26, 2013 8:34 pm

Chris_914 wrote: Welcome to the didn't pass smog so now it time to spend some money club.

You are going down some of the same paths as I did. My high HC at idle was from vacuum leaks, one big one from working on the brake master, and a bad distributor. After I got everything sealed and replaced the distributor it went to high CO. I became exhausted racking my brain with adjustment, second guessing myself, and finally throwing new parts at it.

Mine ultimately turned out to be the heads.

From what I have learned on mine, if you are blowing HC's post cat I going to strongly lean towards a lean misfire. I added a cat in the testing process and fixed my lean misfire condition, that lit off the cat and next test the HC's (lean misfire) were catalyticly converted to high idle CO (rich). My head problems were the cause of needing to run rich at a idle to run decent.

If you GEX stamped into your case don't worry about the exhaust... report in the making on my smog related but completely separate topic.

I hope it's not the heads because that's way beyond overcoming skill with my determination level.

With LM 2 hopefully Ill be able to dial this in. The new CAT should get me close enough to pass smog and the other parts are for "if all else fails" plan.

I just wish the system was controlled via a computer and all tuning handled automatically, it would make finding and fixing my problems so much easier:p

But I bought this bus to have fun camping with and I knew going into it would be a long term investment and it was definitely going to take some money to keep it going for as long as I plan to have it.

Regarding the AFM, when I make changes to the mixture screw on the outside of the unit do I have to re time it? I didn't see any mention of that in the Bentley and my timing was already checked.

Fri Apr 26, 2013 9:27 pm

You have on open loop FI system, trust me it works just fine. L-jet was used well into the age of closed loop systems with the similar AFMs. All gasoline internal combustion engines have the basic needs regardless of type of induction system.

If you don't have one, get a vacuum gauge. Believe it or not this simple tool was spot on at showing a problem. Cheap and report back on idle and 2500 readings including anything other than a steady needle.

I believe it was Amaskeptic that said "listen to what your engine wants" or something like that. If you touched the AFM internally, set it back to known good. Does it still run ok with the idle adjustment all the way in?

Fri Apr 26, 2013 9:35 pm

Chris_914 wrote: You have on open loop FI system, trust me it works just fine. L-jet was used well into the age of closed loop systems with the similar AFMs. All gasoline internal combustion engines have the basic needs regardless of type of induction system.

If you don't have one, get a vacuum gauge. Believe it or not this simple tool was spot on at showing a problem. Cheap and report back on idle and 2500 readings including anything other than a steady needle.

I believe it was Amaskeptic that said "listen to what your engine wants" or something like that. If you touched the AFM internally, set it back to known good. Does it still run ok with the idle adjustment all the way in?

When you say all the way in what do you mean? Idle speed adjustment or idle mixture adjustment? On either one I've never gone all the way (either in or out).

For a vacuum gauge is there a particular one I should get? What other parts will I need to use it?

Sat Apr 27, 2013 11:12 am

Try to be as scientific as possible in you testing methods. You want to try to isolate what you are testing as best as possible and if you find something, that something should be able to be repeated with the same conditions.

Before making adjustments to anything, record the initial adjustment so you have a baseline to go back to as needed. When testing for vacuum leaks don't mess with fuel mixture adjustments at the same time.

Three things can cause high HC's 1) Vacuum leaks, 2) Ignition miss-fire, 3) Leaking exhaust valves. There is probably other but I know these are for sure.

(1)
Checking for vacuum leaks includes all items past the AFM that can introduce unmetered air into the system. This includes the S-Boot, crankcase, AAR valve, throttle body, intake distributor, and intake runners. The intake distributor includes the brake booster, decel valve, ignition vacuum advance, fuel pressure regulator, EEC valve on the air cleaner housing, automatic transmission upto a specific year had a vacuum modulator, and all the hoses that connect these items to the intake distributor. Intake runners include the big hoses that connect them to the intake distributor, mating surfaces w\blocks and gaskets at the heads, and the fuel injectors and seals. I mentioned crankcase above because the vent that goes into the S-Boot is after the AFM and any air leaks at the dipstick, oil filler, valve cover gaskets, vent chimney, or excessive blow-by will cause an unmetered air leak too.

You are going to need a Mighty-Vac are similar hand vacuum pump tool to test the vacuum advance, EEC, decel valve, and fuel pressure regulator (FPR). It also came in handy for holding 15 in\HG on the fuel pressure regulator while I was test running with all the above items listed disconnected and intake distributor vacuum ports capped off. The purpose here was to artificially provide the vacuum signal to the FPR to reduce idle fuel pressure that would mask an air leak by providing more fuel. As you might see here, the air and fuel ratio are intertwined and messing with one has an effect on the other. This is the reason to create a standard on one while testing for problems with the other.

(2)
This can be a rough one to isolate but SGKent recommended a power balance test that works great for isolating problems to specific cylinders. While the engine is running, disconnect a plug wire from each cylinder one at a time and record the rpm drop. The ones that drop less are not contributing as much as the ones that drop more. Check the resistance on the plug wires, Bosch wires have solid wire with resistance spark plug connectors and a resistance core coil wire. Check the rotor's resistance. Check the cap for cracks or carbon tracing. Check the timing with a timing light for a steady mark, it should not jump all around. Dwell should be steady as well, jumping dwell can relate to a distributor that is worn mechanically.

(3)
Check the valve adjustments. Regardless of solid or hydraulic it needs to be spot on. My experience with hydraulics on an old Ford 302 is they can be tightened down enough to hold the valves open too. Not sure if this is the case for ACVWs but I am going to assume it is. Compression and leak-down checks are necessary to look for issues like leaking or burned valves or loose valve seats.

Sear's has vacuum gauges and hand vacuum pumps, might get luck with local auto parts as well.

Sat Apr 27, 2013 11:15 am

he was so close to passing originally it only needed a little tweak. Just have to know which way and the sequence to do it.

Sat Apr 27, 2013 11:30 am

Just went back and reread the beginning, he's alot closer than I was so my procedures might be a bit extreme. My head is still stuck in my problems that started small and turned big.

Also it looks like his test port pre-cat might have been changed to one that accepts an O2 sensor. I has different plug and a lot of welding that isn't present in the one SGKent posted.

Sat Apr 27, 2013 12:40 pm

Oreilly auto parts is down the street from me, is a vacuum tester really going to cost $90?

http://m.oreillyauto.com/mt/www.oreillyauto.com/si...;ppt=C0103

Sat Apr 27, 2013 1:32 pm

ivwshane wrote: Oreilly auto parts is down the street from me, is a vacuum tester really going to cost $90?

http://m.oreillyauto.com/mt/www.oreillyauto.com/si...;ppt=C0103

no and it won't get you past smog either. Did you get a bung welded in for an O2 sensor?

Sat Apr 27, 2013 1:33 pm

ivwshane wrote: Oreilly auto parts is down the street from me, is a vacuum tester really going to cost $90?

http://m.oreillyauto.com/mt/www.oreillyauto.com/si...;ppt=C0103

Oh no! I picked a MightyVac brand tester from Harbor Freight for $35.
http://www.harborfreight.com/mityvac-vacuum-pump-39522.html

They have a vacuum gauge too.
http://www.harborfreight.com/fuel-pump-and-vacuum-tester-93547.html

Sat Apr 27, 2013 2:28 pm

SGKent wrote: ivwshane wrote: Oreilly auto parts is down the street from me, is a vacuum tester really going to cost $90?

http://m.oreillyauto.com/mt/www.oreillyauto.com/si...;ppt=C0103

no and it won't get you past smog either. Did you get a bung welded in for an O2 sensor?

I'll be ordering a new EMICO CAT that will already have one on monday when they are open.

Sat Apr 27, 2013 2:30 pm

Chris_914 wrote: ivwshane wrote: Oreilly auto parts is down the street from me, is a vacuum tester really going to cost $90?

http://m.oreillyauto.com/mt/www.oreillyauto.com/si...;ppt=C0103

Oh no! I picked a MightyVac brand tester from Harbor Freight for $35.
http://www.harborfreight.com/mityvac-vacuum-pump-39522.html

They have a vacuum gauge too.
http://www.harborfreight.com/fuel-pump-and-vacuum-tester-93547.html

Thanks!!

I might as well get a compression tester as well, would this work?
http://www.harborfreight.com/compression-test-kit-66216.html

Edit: Not very good reviews so I may need to look elsewhere for that.

Edit 2:
This compression tester looks better in terms of reviews but is it what I need? Or do I need something that will reach harder to reach plugs?
http://www.amazon.com/Equus-3612-Innova-Compressio...ion+tester

Sat Apr 27, 2013 3:10 pm

I went for Sears on the compression tester. It has individual leads for each sparkplug size versus those adapters. It would be a real pain to extract one of those from cylinder 1 or 4.

http://www.sears.com/craftsman-compression-test-ki...=39869:4:0

Little bit more but it's work great for me on aircooled VWs.

Sat Apr 27, 2013 3:20 pm

did you find a new elbow and muffler too? If you can get the gaskets off in one piece, you can use some red RTV and reuse them if you let it cure overnight. Once you have the cat on and the lighter socket in drop by and we can take a look at what is going on.

Sat Apr 27, 2013 3:31 pm

SGKent wrote: did you find a new elbow and muffler too? If you can get the gaskets off in one piece, you can use some red RTV and reuse them if you let it cure overnight. Once you have the cat on and the lighter socket in drop by and we can take a look at what is going on.

No, do they have to be replaced right now? They aren't welded to the existing CAT (I plan on getting an exhaust hardware kit from germansupply).

Sat Apr 27, 2013 3:33 pm

AutohausAZ has the F-pipe you will need for the bolt on factory style cat.

http://www.autohausaz.com/search/product.aspx?sid=...tor%20Pipe

They actually have all parts from cat to tail pipe but they don't sell the CARB stamped cat model legal in California.