1981 vanagon air cooled runs but no power

[Jilly Bean]

I have an 81 air cooled vanagon.
When my bus is idling in neutral and I goose the fuel the engine revs up like it should. When I put it on gear and give it more fuel it bogs down and won't move at all. Some times it runs fine. Once it coughed three times while I was driving. I put the clutch in and and it continued driving. It's at the mechanic now. He has replaced the distributor cap and rotor and now he is replacing the engine temp sensor. You got any ideas

[MarkWard]

Could the catalytic converter be falling apart and restricting exhaust flow?
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[AZ Landshaper]

vacuum leaks? timing off? dwell not set correctly? whats your compression?

Cal emissions or federal?
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85 Weekender w/ EJ22
Previously
64, 71, 72, 73, 76, 81, 84, 85 & 87 Campmobiles and Westfalias
and a 67 bug.

[Phaedrus]

Air cooled bus doesn't have a cat, unless it's the CA model. In which case, worth peeking at.

You'll probably get more help in the T4/Bay Window forums.

There are so many variables that could cause intermittent running issues. Kind of impossible to help via internet forums. I'd start with doing a full tune-up if it hasn't had one in ~6000mi. Pull the plugs, inspect/clean/replace as necessary. Check/adj the valves. Do a comp check while you're at, see what the health of the motor is. Check/change the points. Make sure all of your engine bay connections are tight. Replace fuel filter as necessary. Time the thing. Make sure your vacuum advance is working properly. If not, pull the advance hose, plug it, and time all in at 30-34 degrees, whatever makes her happy without pinging.

Don't just go randomly replacing undiagnosed parts. That's not what a mechanic does, or should do... and that can often make it harder to actually resolve the issue... See if it still is acting up after a proper tune. It's really hard to tackle something that's intermittent. I need to see/hear/feel the issue in order diagnose/resolve it...
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1986 WBX (Tin Top Camper)

[AndyBees]

I agree it could be a number of things and likely a combo, thus the variables as Phaedrus mentioned.

The suggested tune-up is a good start but leans toward throwing parts.

My 83 Air-cool, purchased at a Dealer in Knoxville, TN, has a CAT.

The mechanic needs to check the Timing and Dwell (assuming it still has a point dizzy). Also, with the Timing light he can see whether or not the Spark Advance is working and working properly. In the scheme of things, a bad coil can be a culprit that's hard to nail down.... keep that in mind.

Typically, if the Temp sensor goes bad or loses ground, the engine will only idle.

Seems the Air-cool has the ground connections on the left side of the fire-wall just over from the Coil. Your mechanic needs to make sure those grounds are functioning properly. The fuel injection system is grounded there.

Yes, as suggested, check for vacuum leaks.

Keep us posted.
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'84 Vanagon Tin-top, ALH TDI. 1989 Tin-top
1983 Air-cool, 225k miles, 180k miles mine. Seven trips to Alaska from 1986 thru 2003.

[Wildthings]

If it is timed according to the book and the vacuum retard can is bad your timing is going to be way way retarded and the engine will run like a pig. Best to time it at 28° BTDC @ 3500+ rpms, with the hoses off and plugged. If the retard can will not hold vacuum do not hook the retard hose back up to the distributor, but use a screw or something to close it off permanently.

[Phaedrus]

[weswsimpson]

I fought with the same issue for two years, missed out on camping with my boys for too long. I even swapped a carburetor for the fuel injection with no improvement. Spent thousands..... Finally I gave up and did a subaru conversion. Best decision of my life! Did it myself and cheaply. Search for "pokevan no more" for my build notes. I love the van now--hated it for far too long....

I believe that it was a worn cam, but decided not to waste my time to find out. The 80-83.5 are red-headed step-children to this group.... and there's not a lot of parts out there or knowledge. Even the transmission is unique to these years! I found much more support with the subaru-swap community.

If you persist with the air-cooled engine you might want to check out this group, I even had the expert scratching his head after messing with it for a day.... www.itinerant-air-cooled.com

Cut your losses and go subaru power!

[AndyBees]

Pokeman, the guy has an Air-cool and is asking for help. I doubt he's looking to do an engine conversion.

When I did my ALH TDI conversion, I used a 1980 DK tranny. Finding parts was as simple as contacting Weddle.

Except for the engine, practically everything else on an Air-cool is pretty much interchangeable with the other WBXers. As for the engine, parts are available for them too.

During the 7 trips I made to Alaska with my 83 Air-cool it performed well. I did have one break-down and knew I had problems before I left (long story) and knew better than to hit the road. Anyway, looking back on how it performed and my experience with the 1.9 WBXer and 2.1 WBXer, if I had my choice between the three to drive back to Alaska, I'd take the Air-cool hands down. A properly tuned Air-cool is a hoss. But, that's why I installed an ALH TDI in my 84, to make those long trips.
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'84 Vanagon Tin-top, ALH TDI. 1989 Tin-top
1983 Air-cool, 225k miles, 180k miles mine. Seven trips to Alaska from 1986 thru 2003.

[weswsimpson]

[quote="AndyBees"]Pokeman, the guy has an Air-cool and is asking for help. I doubt he's looking to do an engine conversion.

Yep, I had an air-cooled that lacked power too.... I wish someone had "helped me" by advising me to ditch the under-powered engine and go with a Subaru, I would have been time and money ahead of the game.

[weswsimpson]

Adjusting the valves is another important tune-up thing to do... but good luck trying to adjust them with those hydraulic lifters! If they sit for a while, they won't pump up.... then your adjustments are all off.... what a nightmare!

Read up about them here:

http://www.ratwell.com/technical/HydraulicLifters.html

[weswsimpson]

it could also be the air flow meter.... oh, the nightmares are returning just thinking about it....

[weswsimpson]

or a fuel filter full of rust...

[Wildthings]

[MarkWard]

Nice thing about a Subaru conversion is you will never have another problem. Ever
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[74superTN]

actually adjusting hydraulic lifters is super easy...Don't knock an aircooled engine, it sounds like you wouldn't have been happy no matter what, complaining about everything.
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73 Thing
80 Vanagon Westy

[calo1956]

Patients my friend, it takes time, that i can attest to! Mine is a 80, and after the rebuild it took 6 months to get it to the point of running awesome and driving it daily! And now when you drive past me, you'll know its me because I'm grinning ear to ear! You'll get it, your in good hands here, Our fellow Samba members got me to this point, and i thank them all !
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Enjoy the ride....
72 bug
80 westfalia

[danfromsyr]

wet air cleaner,
mice nest in air cleaner
water in fuel from bad seals on top of vapor tanks in wheel wells.
cracked S boot from throttle body to AFM
unplugged AFM
clogged fuel filter/bad gas
tired fuel pump not able to make pressure/volume

to name a few.
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[AndyBees]

[metropoj]

For me, the compression test is usually the first thing I'd look at before I start throwing parts and a mechanic's 'On the clock" time (money) at it.

After that, all the basics of ground wires, Vacuum hoses, etc. AT least you stand a fighting chance .

Good luck on the hunt.
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John.
86 TiiCo powered Westy.