Bad gas??

[thomast]

1985 Westy 1.9.

1/2 tank gas cruising along at 55mph for about 25 minutes, no issues. Van starts to sputter intermittanly all of a sudden but I'm able to maintain speed.

Slow down to 3rd gear going through small town (in Wisco) and it really starts to sputter/jerk/jive. I think it's going to stall, but keeps running and i'm able to get back up to 55/60mph with some sputtering.

Stop at a stop sigh and the van idles nice and smooth. Start off and heavy sputtering ensues but again able to get back up to 55mph with mild sputtering at 55. Drive 7 more miles to gas station. Put in a 1/2 tank of 91 octane, 1 bottle of STP gas treatment.

Start van and drive for 2 hours to home with not one single sputter after fill up.

I'm inclined to think it was the gas, but since it was only 1/2 tank down, does that make sense? Was it the act of shutting off the motor that helped eliminate the issue?

Nervous about driving it again until I have a good idea of what might have caused it to sputter.

[MarkWard]

To eliminate the possibility of contaminated fuel, I would remove the fuel filter with a glass jar on hand and blow through the filter backwards into the jar. Let the fuel settle and you will have an idea of what is in your tank. If it is clear and no water on the bottom, it might be something else.

Intermittent problems are the hardest to figure out. You need to be ready to test things while it is acting up.
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[dobryan]

Any chance you were driving in the rain when this happened?
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Dave O
'87 Westy w/ 2002 Subaru EJ25 and Peloquin TBD

"To travel hopefully is a better thing than to arrive." Robert Louis Stevenson

MD>Canada>AK>WA>OR>CA>AZ>UT>WY>SD
https://www.thesamba.com/vw/forum/viewtopic.php?t=620646

Building a bus for travel in Europe (euroBus)
https://www.thesamba.com/vw/forum/viewtopic.php?t=695371

The Western Syncro build
https://www.thesamba.com/vw/forum/viewtopic.php?t=746794

[Wildthings]

When the gaskets and hoses on the tops of the expansion tanks and the gas tank itself go bad water thrown up by the tire will get into the tanks and cause the symptoms you are seeing. Time for a reseal.

[dobryan]

^^^^ This.
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Dave O
'87 Westy w/ 2002 Subaru EJ25 and Peloquin TBD

"To travel hopefully is a better thing than to arrive." Robert Louis Stevenson

MD>Canada>AK>WA>OR>CA>AZ>UT>WY>SD
https://www.thesamba.com/vw/forum/viewtopic.php?t=620646

Building a bus for travel in Europe (euroBus)
https://www.thesamba.com/vw/forum/viewtopic.php?t=695371

The Western Syncro build
https://www.thesamba.com/vw/forum/viewtopic.php?t=746794

[thomast]

It was snowing / sleeting a bit will I was driving, but not heavy at all. I drove it in heavy rain about 3 weeks ago for about an hour with no issues.

Thanks for the comments. I appreciate the input.

[bobbyblack]

I'd also go with 'was it a puddle you hit' kind of question... On my recent 'hit a puddle' resulting with the need for a full reseal (not just the fuel tank, but the expansion/rollover ones too). Careful on those plastic tank nipples. After you use a razor blade to loosen the old vapor lines, be sure to clean the stems out good, they are often yet another remove/clean/reinstall AFTER getting the whole thing fully sealed up - for whatever reason, those nipples grow crud in them, and it blocks the vapor/fuel flowing, and then you get even stranger problems. ALSO, be aware that if indeed you are suffering the need for a reseal, you've nearly always got an issue where the charcoal tank in the rear passenger wheel well will have a plugged lower breather tube. You'll get everything done, fill the tank, go for a spin, and the blocked breather will result in an imploding fuel tank... Ask a few people who it's happened to. No fun. That's when you get to start ALL over. New sender, new tank, maybe salvage the reseal kit, etc.

Blah.

Good luck tho.

-bobby
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'87 Westy 'Flossie','86 Westy 'R1','86 tintop GL - Subi2.2 'J2','83.5 stock tintop L 'ZoomBus','74 Karmann Ghia, '63 Notch

[Wildthings]

[bobbyblack]

[syncro2x]

I had this happen with my syncro when coming home from camping. Woke up to slushy wet snow. Van coughed and sputtered barely making highway speed and sucked gas like crazy. After about an hour had to buy fuel. Filled her up and figured it would be hard to start if start at all. Fired up right away and ran perfect all the way home. Seemed like the comfuser got reset. Did it again, about 3 months later when I hit a large puddle off roading. Sealed up everything electrical in the engine compartment with garbage bags and twisties. Never done it since.

[syncro2x]

I had this happen with my syncro when coming home from camping. Woke up to slushy wet snow. Van coughed and sputtered barely making highway speed and sucked gas like crazy. After about an hour had to buy fuel. Filled her up and figured it would be hard to start if start at all. Fired up right away and ran perfect all the way home. Seemed like the comfuser got reset. Did it again, about 3 months later when I hit a large puddle off roading. Sealed up everything electrical in the engine compartment with garbage bags and twisties. Never done it since.

[Ahwahnee]

Are you familiar with the Vanagon Syndrome? Search to reveal details.

A simple test for that problem is that switching the ignition off then on clears the problem until next time. Not even necessary to stop the vehicle (f you are careful) just switch off & on again.

Fix is a capacitor added to the AFM.

[IdahoDoug]

I just had this happen two weeks ago. I filled up and it was instantly gone for the remainder of the trip. I have a theory the WBX may be slightly sensitive to fuel contamination for whatever reason. I had randomly put a new prefilter on my van hours before leaving on that trip, so it was not dirt.

I suspect it was water and I further suspect every fall when the fuel stations up north switch to the winter fuel, the first batches tend to or may be older fuel from last season mixed with fresh or some variation. It's never happened to me in the spring and I suspect that's because the "summer fuel" may be what's in constant use year round by our southerners, so there is no summer fuel sitting and waiting. Where as for winter fuel there may be some sitting.
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1987 2WD Wolfsburg Vanagon Weekender "Mango", two fully locked 80 Series LandCruisers. 2017 Subaru Outback boxer. 1990 Audi 90 Quattro 20V with rear locking differential, 1990 burgundy parts Vanagon. 1984 Porsche 944, 1988 Toyota Supra 5 speed targa, 2002 BMW 325iX, 1982 Toyota Sunrader

[Abscate]

I’ve found the “ bad gas “ diagnosis to be incorrect 99% of the time.

Pulling off 250 ml into a glass container is a good diagnostic, though. If you can’t see water, it is something else.
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.ssS!

[bjrogers86auto]

Sounds like the exact thing that happened to me and it was water in through the expansion tank seals.

It's not immediate. The rainy day could have been a few days before the symptoms. I drove in heavy rain on a Thursday and had issues on the Sunday of the trip.

Methyl Hydrate or "dry gas" as you Americans call it works to help if its not excessive.

Brian
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86 Vanagon GL Westfalia 2.1
18 Nissan Frontier Pro 4X
19 Honda Civic Hatchback

A little rudeness and disrespect can elevate a meaningless interaction to a battle of wills and add drama to an otherwise dull day. Calvin and Hobbes.

[DanHoug]

if you pull the filter off to backflush and check smudge, DO NOT put it back on. for $13 put a new one on. it is typical for an older filter to backflush with black stained stuff.

i've found vanagon plug wires notorious for going bad quickly, resulting in poor running in wet or humid weather. also, make sure the white porcelain insulator on the plug itself is clean. they usually are NOT. take the black conductive RFI shield off the distributor and throw it. you don't listen to AM radio anyway. clean the distributor cap and coil top of dirt, they must be shiny clean brown Bakelite. throw away the cover on the coil also.

keeping the entire secondary ignition system clean is old school maintenance that is forgotten as nearly all new cars have COP.. Coil on Plug. it just isn't an issue anymore but we're driving antiques, that require antique thinking to keep them running smooth.
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-dan
60% of what you find on the internet is wrong, including this post.

'87 Westy & '89 Westy both 2.1 4spd

Past projects can be found at--
www.thefixitworkshop.com

[bobbyblack]

I've had thoughts about how hard it is to "see" what we have going on. My 3 tractors (antiques, of course) have a glass blow, and a nice shutoff inline, so as to take the bowl off and get the crap and water out. Airplanes have a little thingy at the bottom of each fuel tank that you press a needle tip into that is connected to a viewing jar. Easy easy easy. Whats the deal? Why are there not easy to find kits to add something like these options of modern vehicles? 5 seconds, you'd know about crap or water in fuel. Rather than 3 days of forum posts.

-bobby
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'87 Westy 'Flossie','86 Westy 'R1','86 tintop GL - Subi2.2 'J2','83.5 stock tintop L 'ZoomBus','74 Karmann Ghia, '63 Notch

[Abscate]

[MarkWard]

When I was in flight training, part of the preflight inspection was to draw fuel off of both wing tanks into a clear glass cylinder. It was not so much for getting a bad load of fuel, but the problems with condensation forming inside the tank when it was sitting and not completely full.

The vanagon filter is easy enough to access and if there is water in the fuel, some will collect there. Even when I do a service, I like to drain the fuel filter into something just to see what is there. In other words, it's easy to eliminate water in the fuel and get on to checking other things.

My diesel filter has a drain from the factory. Again, I don't think VW thought the seals would fail and let water in. Part of owning a VW diesel is to occasionally drain the filter between filter changes.

When VW first started selling diesels, we had a few marine folks that wanted to add a Raycor in addition to the stock system. They just wanted the extra filtration and to some extent, "see" what was there. Boats are even more prone to water in the gas.
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[DanHoug]

high pressure, water separating fuel filter, with drain port..

http://ph.parker.com/us/en/high-pressure-fuel-filters-water-separator/110a
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-dan
60% of what you find on the internet is wrong, including this post.

'87 Westy & '89 Westy both 2.1 4spd

Past projects can be found at--
www.thefixitworkshop.com