Q: Tuning Air/Fuel Mixture on 1977 Bus with Fuel Injection

[equinox]

Background:

Colin is a great guy! Very friendly and extremely knowledgeable! It was great to have him over and 1. Try to figure out what was going on with the bus and 2. Get it at least run able where I can take it from Place A to Place B without worrying about breaking down and also not die during deceleration and coming to a stop.

Being a smart and well educated person, and likewise having worked on cars as teen and person in my early 20’s, it’s now been 25 years since I really worked on a car myself besides brakes or oil changes and I had ZERO experience with VW’s and buses.

Colin took the time to draw up and explain things and working 1-on-1 and me doing the work, I was able to gain hands-on experience that doesn’t come with shipping the bus or vehicle to the local mechanic.

To Summarize:
We did many starts and trips and testing the vehicle in park and under load. We did a compression check and vacuum check and checked all of the valves and adjusted them ourselves. A few of the things we did are (and not in this order):

1. Replaced many cracked hoses, thou leak check with WD-40 resulted in no air leaks including the S-hose.
2. Adjusted all valves.
3. Adjusted the AFM including wiper and remapping.
4. Adjusted the air bypass
5. Replaced the super strong accelerator return spring with a more appropriate one
6. Replaces the air cleaner (the one in there was horrible and did not accommodate the appropriate area and seal
7. Replaced the Electronic Ignition on the distributor with a points-type one. It was missing the appropriate clip to retain the rubber boot going into the distributor. I fabricated one out of retaining clip(s) I had bout at HomeD recently. Bent it a certain way and cut out a square with a dremel. Worked PERFECTLY! Soo if anyone needs to know or see it, let me know!
8. Replaced all ground spade connectors
9. Adjusted the timing and idle to ensure right
10. Moved the distributor 1 tooth (evidentially it was not in the correct orientation and hard to get to the distributor screw. Colin said they put it in wrong and why orientation was incorrect. A quick pull and spring and resetting and boom..in the right spot.

What We Found:
A lot of the above was inconclusive. What we did find out is that…
1. The #3 cylinder is not working. Pulling the wires made no change to engine tone or speed. There is something wrong with it and the bus is basically running on 3 cylinder. The spark plug threads looked like shit, so Colin was having a little bit of a time getting the compression gauge on. It measured like 80-85psi and my most recent readings last year showed it low at 110 psi on that cylinder and about 145-150psi on all others, so something with that cylinder.

Colin is adamant that points are the way. I personally don’t think so for this reason…if it runs better with it, it’s only because of the condition and blowing gas out #3 and maybe messing with the air/fuel and computer throwing everything off. What adding the point distributor did was it changed the engine from running rich (correct me if I’m wrong on this Colin) to running EXTREMELY lean! We had to put the bypass all the way in and still was lean! That’s why the AFM had to be adjusted and remapped to get it to idle right and I think ended with the AFM at 4 turns out.

When we did the initial drive, the engine was chattering like anything. Colin said you hear that? Yep. He said the hydraulic lifters were not pumping up. From checking and adjusting the valve, it was inconclusive, but maybe the bottom of a valve or cam profile is worn? In any event and after a long while and heating up, it did simmer down.

Another item that Colin suggested did not appear to be functioning correctly is the auxiliary air regulator. The idle is not as good as it could be. What we did DEFNITELY helped, but this component may not be working and I should look to replace.

Current Status:
In the end, the vehicle went from dying when slowing down and stalling, running very rough, and losing power/backfiring under load.

It now idles significantly better and I can fire it up and take it from one place to another. It is running on 3 cylinders (root cause unknown) and aux air reg may not be working. Colin did his job to get it running (not his fault it cannot be completely fixed at this time). It does run rougher and need to baby the gas pedal when cold until brought up to temperature.

Next Steps:
With the #3 cylinder causing loss of power and the current condition, I will continue to use it, but need to contemplate the next steps. Any suggestions? Is it worth it to dig into the root cause only to repair the issue on an engine last rebuilt 10+ years ago, thou the other 3 cylinder appear fine, but between distributor 1 tooth off, threads on valve train, etc., it may not have been exactly right? Or, if I want this 100% reliable and for cross country trek’s, should I just use and in the meantime (or charge) and save $$$ and just drop a new rebuilt long block or shortblock in (again like I was thinking 3 years ago along with contacting Colin) and call it a day?

[SGKent]

I would replace the plug wires unless they are new already. Check the EGR for leaks. Also check #3 injector if Colin didn't already, You can swap the #3 and #4 injector wire to see if it is the connector. A NOID light is cheap and can tell you if the injector is getting a pulse.

The reason points are best on the 1977 is that the ECU relies on a pulse from the coil to shape the injector pulse. That is how Bosch designed it. When an electronic ignition is used, some brands change that pulse so the ECU gets confused and causes problems that are hard to diagnosis. Just be sure to carry a spare set of points and keep the distributor cam lubed once in awhile. I put a little lube on it when I change points, and again at each oil change. Also a few drops of oil on the wick under the rotor when changing points.

You have enough compression in #3 to fire so that is why I would look at the wires or injector / connector first. You got a lot done in a half day. Best guess is you'll find that gremlin in #3 and be back to normal. That may also be why the compression is down a little on #3. It may come back up once it gets some use.
_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[aeromech]

Try plugging the brake booster line and see if #3 comes back to life
_________________
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[aerosurfer]

Did you confirm that #3 is actually getting fuel? Did you swap the fuel injector plugs on 3 & 4? If the plug is not seated on the injector or there is a break in the wire and it’s not firing, then of course it will show no change in power when the plug wire is removed.

Check the series resistor for a broken wire. If you swap 3 & 4 and the problem follows, you have isolated it to electrical with the harness or other components

Again still no pictures with this thread....
_________________
Rebuild your own FI Harness..My Harness

77 Westy 2.0L Rockin and Rolling Resto!

72 Sportsmobile (sold)
79 Tran$porter... Parts car money machine (gone)

[SGKent]

Aerosurfer and AeroMech made excellent suggestions. I say this not to just comment on their posts, but to elevate their suggestions to your to do list.
_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[aerosurfer]

[SGKent]

maybe Gary did not see this.

Best guess is that the brake booster and decel tee into the plenum right near #3. A leak there would lean out #3 more than any other cylinder.
_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[Randy in Maine]

Also...

I wonder if the problem with the #3 spark plug hole has anything to do with it?

I can't remember if this car is an automatic transmission.....

[Amskeptic]

Do you think I left any stone unturned? With this guy and his eleven pages??

Seriously??

Yes, we swapped wires and injectors, but why bother? The damn starter draw showed beyond a shadow of a doubt that the compression was low on #3. So did the 44% leakdown (was it 44%?) We established that we had spark and fuel the instant we looked at the plug and saw all the evidence we needed that it was warm, brown at the insulator, and pulling the fuel injector plug did cause rpm drop.

Equinox is understandably not yet relinquishing his confusion over the stupid Pertronix unit being responsible for that horrible running, bucking and back-firing. I did say the misfires made for a richer mixture, and now that we have much more frequent and reliable combustion events, the actual fuel mixture is leaner than it was. SG Kent, I agree that ECU likes the points/condensor trigger pattern better than a Pertronix.

This car finally drove beautifully for 3 1/2 cylinders once we had addressed a bunch of stupid issues, like lousy valve adjustments and split vacuum hoses and the worst cheap air filter I have seen. This bus gave us good acceleration, smart upshifts, excellent kickdown, and docile trolling into the garage. But that weak cylinder is not helping keep the airflow smooth through the AFM.

Equinox, as you all know by now, is a bright committed guy chafing at the bit to get things perfect NOW, but we have some details to deal with - the good news is that the house did not get cleaned off the foundation . . . yeah, ask him.
Colin

_________________
www.itinerant-air-cooled.com

[Globespotter]

Valiant efforts and very good advice. My gut is that some people just shouldn't have a bus. Sell it to someone who will appreciate and love it and move on. It's been 3 years for crying out loud.

My 77 Westy (that Colin & I worked on a couple of years ago) dropped the intake valve seat on #3 recently. The engine is out being rebuilt now.

I'm not screwing around with $1000 here or $2000 there at some mechanic who doesn't really know what they are doing. I'm biting the bullet and getting a proper rebuild at an air-cooled specialist.

Do you love your bus? Then treat it like you do. At the least, change the damn air filter.
_________________
1977 Westfalia - October 2015 - Current
1971 Super Beetle - May 2012 - Current
1979 Westfalia - 1986-1991
1971 Super Beetle - 1977-1980

1971 SB Survivor Story: https://globespotter.com/
Road Trip Thread: https://www.thesamba.com/vw/forum/viewtopic.php?t=511800&highlight=
My 77 Westy Thread: https://www.thesamba.com/vw/forum/viewtopic.php?t=647114&highlight=

http://vw-mplate.com/mcode.php?lang=EN&id=30990
https://vw-type2-id.xyz/mplate/72067382

[Amskeptic]

[Zeen]

That's certainly a solid, nice looking bus, worthy of all your effort and investment. Good luck!
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The consequences of your decisions should not be confused with fate.

[SGKent]

you are doing a good job. Hang in there. Really. You are close to an answer.
_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[equinox]

"I would replace the plug wires unless they are new already."

Already new. Replaces them, plugs, and coil last year.

"Check the EGR for leaks"

Colin did and spray a lot of areas with WD-40...no significnt change in engine running. The lines with cloth had the runner worn and cracked, no leaks were found, but we replaced with new hose (just rubber). Can I get any of that cloth covered rubber hose??

"You can swap the #3 and #4 injector wire to see if it is the connector."

"Also check #3 injector if Colin didn't already, You can swap the #3 and #4 injector wire to see if it is the connector"

We checked by moving the injector wires as well as computer harness...nothing significant noted. I like the suggestion of swapping injectors and see if it follows it! I don't have or know what a "NOID" light is. I did buy a complete SET of injectors! So I have available and could put on this engine...or a new one!

Yeah, Colin mentioned the reason for points and differences. It's crazy it went from super rich to lean witht the swap, but again, with the electronic, it is probably compensating for the messed up cylinder and engine. If corrected and good EI, electronic would probably be a better way.

The #3 had like 100 psi last year and only 80-85 psi this year! Seems like a significant trend in the wrong direction, but if the plug threads are shitty and stripped, I wonder how much is blowing past it?? You could see black half way up the lnog threads!! Can this plug thread be repaired without pulling the engine or is it gonna put a lot of metal in the cylinder and suck?

"Try plugging the brake booster line and see if #3 comes back to life"

Ok. Colin pulled a few lines and tried things, but to no avail. Not sure if he did this, but I can try it.

"Did you confirm that #3 is actually getting fuel? Did you swap the fuel injector plugs on 3 & 4?"

No, I don't think so. We did not check spray of injectors or swapping or anything that I am aware of and due to time. We just wiggled wires and checked of changes, but non appeared.

"Check the series resistor for a broken wire."

I did check the resistance thru the harness previous and was like what was it 9 ohms or whatever. It was fine all cylinder. I WILL try either swapping injectors, or putting on one of my brand new ones and see what happens.

"I wonder if the problem with the #3 spark plug hole has anything to do with it? I can't remember if this car is an automatic transmission"

Yeah, I'm wondering about #3 spark plug threads also...at least for lost compression and mixture due to loss. YES, it's an AUTOMATIC transmission. I wanted a maintenance-free truck, so...auto trans, EI, fuel injection, etc.

"Yes, we swapped wires and injectors"
Oh, looks like Colin did that. Yes, we got a LOT done in the time alotted and went right to work and at it!

"So did the 44% leakdown (was it 44%?)"

Leakdown from 4/28/2015 showed 1-5%, 2-4%, 3-19% (leaking mostly from the rings, some for the exhaust noted), 4-2%

"worst cheap air filter I have seen"

That air filter was ridiculous! Thanks for the new one. Damn, that thing fits nice nested in the plastic thing! I wonder if I should fix that diaphram in it at some point?

"the good news is that the house did not get cleaned off the foundation"

Yes, a storm front was arriving and tornado alarms going off right (a rarity where I live) when Colin and I arrived at the house! We didn't get sucked up in the tornada...but I had to scramble as soon as I got home and move my Silverado-Blackout Edition and Solstice into the wood to protect from the hail...which DID happen and heavy rainfall while our buses where nestled next to each other with us in the garage!! :O That was INSANE!

"Sell it to someone who will appreciate and love it and move on."

That's NOT happening. I think Colin can convey...I'm upset my bus is sick and trying EVERYTHING to fix it, but have a passion for it. As he said, I am very smart and very well educated...just no background at all with VW and buses. I had hands-on experience with Colin and with my prior experience, ramp up knowledge was quick. A VW, German engineered car, and bus is quite significantly different that an American (GM/Ford/DCX) vehicle!

"I'm biting the bullet and getting a proper rebuild at an air-cooled specialist."

I'm down with that and why I suggested it. Did I replace the air filter...YES, I DID (and recently)!! I had no idea it (filter) was a piece of shit, so I think you're being a little short-sided, because your vision of the situation is flawed. I love my bus. I've put $28,000 in it. I replaced the air filter...and everything in it, except the engine!! I'm trying to see if I can get it work before I throw in the towel, say funk it, and yes, just put in a complete rebuilt long block...which I'm willing to do...if I have to. I've lost Summer, after Summer, after Summer and why I'm saddened. ...

"Equinox is over the hurdle of disappointment of "professionals", I do believe."

Yes, I am impowered now and enough so that I am on vacation for 9 days starting tomorrow after work. I look forward to really, really digging in further starting this weekend and make my final judgement on next steps. The money I spent with you Colin was invaluable especially compared to these "experts", like Munks, who just kept diggning into my pockets and never resolving the issue or really even making it run consistently, which you have brought it to this status, so thank you!

"That's certainly a solid, nice looking bus, worthy of all your effort and investment. Good luck!"

Yes, thank you, it IS. I had cabinet maker friend from the casino make custom cabinets and kegerator for me! Looking forward to installing it...once I get working 100%. Interior and seats are all new, new canvas top. It's not "perfectly" restored, but very nice. I've had offers for $28-29k for it which would break me even and I turned it down and said...I haven't even used and enjoyed it yet...NO. Let me use it for another 10 years...then maybe yes and we'll talk pricing at that time!

"you are doing a good job. Hang in there. Really. You are close to an answer."

Thanks! Yes, I feel I am. Things are finally getting checked off the list. Looking forward to working on it this weekend and over the next week!


So again, current status is running, lifter taking forever to pump up, at least on that day, but maybe because sitting soo long, last start ups after Colin left, no problem, but there is the issue no holding idle well....until warmed up. Soo, may be that aux enrichment thing. I'll check for leaks and swap injectors ensuring not a clogged situation or something (I think original 40YO+ injectors) as well as other suggestions trying to root out the issue. If I can't and to have piece of mind, I may put in a new engine. I just need to check on the labor expense. How hard is it for me to do myself with auto trans?? Too in depth at this point...no issue paying someone.

[Amskeptic]

[equinox]

I haven't logged the milage, so unsure, I just burnt thru the 1/4 tank or so. I gassed up today and noted the milage, so I can log it and see how MPG is.

Today was most of the driving. I changed out the AAR this morning. The original unit was a 0 280 140 101 / 022 906 045 A. The new unit I got from Bus Depot is a 0 280 140 188. I hope this is an ok cross reference. The site said it was for my bus. All of the connection are the same and installed perfectly.

The idle still won't hold cold. It seems to hold idle sooner (sooner after cold start), so maybe the new unit did...something. At the very least, it's new and not 40+ years old, so I might as well keep it and send the old one back as core.

There was no evidence of lifter noise, even cold! Soo, this is good. maybe just needed to be driven?!?

Likewise, I pulled the spark wire off #3 just to see if any change...sure enough it sputtered and wanted to die, replaced and smoothed right out...soo appears #3 was working today!

There is still that hideously loud trans noise! I went thru the gears and appears in everything except Drive (no noise even in Drive at low idle). I will contact the trans company and let them know they need to look at it.

Attched is a link a video of the Trans noise - https://drive.google.com/open?id=1XxORM3K-f6yk-2s7cz0_qgDJ214YJ3Eg

[equinox]

Van ran great today!

Started right up and idled on it's own (even when cold)! No lift tapping. I checked the trans fluid level and it looks like this, warmed up, and in Neutral (as it says to do on the stick).

The fluid level looks to be WAYYYY over and I wondered what issues this can cause and possibly causing the noise??

Funny. The manual says drain plug, but there isn't one!! In the photo, the fill tube goes into trans and plug in pan to drain it. On mine, tube goes into pan, so I had to loosen and pull out the tube to drain and fill back up to appropriate level.

I also ensure tires were inflated appropriately to tag by steering wheel.

The average MPG was about 13.5MPG over 100 miles. 70% on highway at 70MPH and 30% at road speed of 50MPH.

Although the trans did not make the whine at first, it DID when heated up! Soo, it has to go to the trans company that did it. Occures only in P, N, and R...not D. I'll target 9/1 thru 9/9.

I'm taking a week off during that time, but next week is the BEST cruise....Hines Drive Cruise.

The Woodward Cruise was today and this weekend (which I don't partake in as gimmicky and filled with every day cars and "dream cars" and Hines Cruise next week (which is the very best cruise period in my opinion and you HAVE to have a vintage vehicle to enter the event and there are 30-60,000 vintage vehicles ONLY)! - http://cruisinhines.com/