Start/restart or stalling problems

[rgifford]

My 82 westy aircooled stalls at stops after the engine is throughly warmed up. The engine runs fine when it has been running for the first 20min. At a stop the engine is running but as soon as i depress the accelerator it cuts out and i wont be able to start the engine untill 5-10 min. has elapsed. There are two related fixes on these message boards;one is getting the signal trnsformer wiring harness and the other is soldering in a mfd capacitor across #2 and #4 contacts on the air flow meter.Both of the fixes refer to the "vanagon syndrome" I checked to see if a wiring harness has been added and to my inspection - no. I would like to try the 22mfd capacitor fix first. What would you or anybody out there recomend that has gone through this problem? Has anyone tried the capacitor fix and does it work? are there any detail drawings or written instructions on installing this fix?

 

[Capt. Mike]

AFC system is, for all practical purposes, the same as the late Type II's, you may find the trouble-shooting chart posted on my pic site (link from home page, or http://briefcase.yahoo.com/captmike67 ) in the tech diagrams folder easier to use, but I would still double-check the spec values with the Bentley manual for your car.

You symptoms indicate something is running amiss after you reach a certain temperature, possibly one of the sensors, cold-start enrichment system, or idle-transfer switch. The only cure is the painstaking check-out of the entire FI system.

Although Vanagon Syndrome is exclusive to Digifant systems, it's symptoms are not, as all VW FI system use an air-flow meter that can misbehave in that fashion from other sources. However your symptoms are not the same as Vanagon Syndrome, which is a part-throttle and throttle transition malfunction.

 

[mattrick]

I am experiencing a similiar problem. My Westy is a 1982. It starts up cold fine. It runs fine until I shut it off once it comes up to operating temp. It does not stall at stop lights or when braking.
It just cranks over but will not fire when at operating temp. I have had a '73and '79 bus but have never experienced this problem.
The '73 was carbed and would have vapor lock sometimes.
I also have worked on FI for type 4 engines and have never seen this. I have worked on both MPC and APC systems. 914 or bus.
Any sugestions.

Matt.

 

[Capt. Mike]

Without some more info based on the checks you've already run, the best we can do is a couple of generalities.

That you don't have any stalling or running problems, just the hot restart, I think it rules out running side of the FI & ignition. I think you can also rule out the starter if it's spinning freely. Vapor lock on the FI systems is extremely rare due to the high pressure of the fuel system. It over produces and then bleeds excess back to the tank.

However, the dead symptom when hot leads back to the FI. It sounds a bit like the flood symptom of a defective cold-start valve or intake air sensor. Do the FI system check on starting page 24.38 of the Bentley. That can be done with only a test light & ohm-meter and will confirm or eliminate 3 or 4 of the most likely candidates in the FI system related to starting. Good luck.

 

[TVDOC]

In response to the post posted 11-11-2000. My 83 vavagon starts ok at first but after warm up is hard to get started again. Acts like it's flooded. If I keep on the starter long enough and hold down the excelerator pedal it may start eventually if the battery still has power.I don't have a bently manual so anything you can sujest would be very helpful, thanks, Neil

 

[Capt. Mike]

Sorry, best advice we can give is get the Bentley. Repairs without the shop manual is like planning dinner without labels on the cans. [Also note Message Board Guideline #2.]

 

[Capt. Mike]

itional power with colder temperatures.

You've posted this as "getting spark", but are basically describing a bad battery which isn't likely to give you a strong ignition. Did you check the plugs for spark and coil output? First, I'd go to the TIPS forum and read the thread on batteries. (While you're browsing the site, also read the one on oils for winter viscosity tips.) A bad battery can take a 'surface charge' and read 12v -- even occassionally start the car. But as soon as it's asked to generate a stiff load, collapses. Do the load & specific gravity tests described there.

Did your mechanic actually TEST the alternator and regulator? If the battery tests good, they may not be properly charging and give some of your symptoms. "Shaky" & "loose" connections don't normally give your symptoms. The battery is the buffer so the engine isn't affected by those irregularities.

Since your system is FI, the need for a new fuel pump raises questions. It's not common for the electric pump in such systems to be "intermittent". (Unless, of course, they are getting intermittent power.) It may have worked through a slug of moisture or debris that would have been picked up and corrected by the removal and bench tests that should be performed before a replacement anyway.

Dashboard clocks take almost no power and not enough to drain a healthy battery overnight. The digitals take no more than a digital wristwatch and even the old dial style were usually mechanical clocks that used an electric "winder" that would only rewind the clock for a couple seconds every few hours. If it was shorted, it would not keep time or would blow fuses. I doubt there's anything wrong with it.

No offense to your mechanic, but if it's as described, it doesn't sound like proper shop procedures were followed.

'79 Westy will not start

atlantagreenwesty Junior Member # 1411 posted 06-30-2001 09:20 PM

A few days ago my bus stalled for the first time at a drive-thru, then had a hard time restarting. I got it started and then drove to work, having to keep the RPM high so it wouldn't stall. Did the same thing bringing her home. Now it won't start at all. It fires, and it hiccups hard a few times like it wants to start but won't. On the second or third try, it gets spark just won't turn over. The tailpipe came off a few weeks ago but I don't know if it would allow to much air to go back in the exhaust? Being the novice mechanic wanting to learn, I have read a lot of the posts and have ideas but still a bit confused. Any help would be great.

Capt. Mike Moderator Member # 11 posted 07-01-2001 07:31 AM

When an engine is hard to start but will run at high RPMs yet not idle down or stay running, it often indicates a vacuum leak. i.e. the engine is getting too much air and the fuel-air mixture is too lean.

You also have a cold=start system (Bentley 4.2) and a thermo-time switch (Bentley 4.3) that could give similar symptoms.

clementine1980 Junior Member # 1091 posted 07-02-2001 04:41 PM

I have recently acquired my first Westy. 1980 Vanagon 2.0 fuel injected. When I purchased it the previous owner said that he had it running about 9 months ago but had not started it since then and when it did run it only ran for 30 sec. I went through and tested the MPC and all the neccessary connections seem to be there. I tested the injectors and they were not firing. The engine cranks over and has been timed correctly. I put in new points and condensor and a new Combi Relay and all of a sudden the injectors are firing. We have fire, we have spark, but the plugs are dry or barely damp after 60 sec of cranking on the engine. I am at a wall, please help...

Ignition problem

Stampy Junior Member # 999 posted 06-16-2001 10:14 AM

I have a '79 Westy with a Cali engine but the FI system is non-cali (I don't have an ignition control unit). I believe the problem is with the ignition, the engine turns over and I can hear the fuel being supplied to the engine but it doesn't start.
Within the past year (with less than 300km of driving) the following have been replaced in order

- Points
- Distributor Cap
- Spark plug wires
- Battery
- Coil
- Condenser

From the coil I have the following wires:
Terminal 15 (+)
- From aux heater blower
- To double relay
Terminal 1 (-)
- To condenser
- To AFC unit

The tests I have done and results that I found…

The coil
1. Measured 12.4 volts at terminal 15 with ignition switched on (is this too high?)
2. When cranking I get a good spark at a distance of 1/4", blue in colour but with a couple orange flashes.
3. With the engine turned so that points are closed and the ignition on
a. from terminal 1 (-) to ground reads 1.3 V (should not have a reading)
4. Used a pencil to open the points when I opened them I got a small spark.
a. from terminal 1 to ground reads 12.2 V
*NOTE: The points and the (+) side of the coil got quite hot during this test (a clue perhaps?)

The new coil is a 12V Wells it doesn't have a visible resistor but neither did the old Bosch coil.

I measured the resistance between the coil terminals and got the following readings.
1 & 15 - 1.1 ohms
1 & 4 and 4 & 15 - flashes of readings between 1300 and 1900 ohms. (not a steady reading)

The coil got really really hot one time when I was running these tests could this have fried my new coil?

The condenser
1. I took off the wire from terminal 1 (-) and with the ignition on I put my test light between terminal 15 and the wire going to the condenser. No light. So it tests ok.

Thanks in advance for any help that you can offer.

Peter & Stampy (named after my fish that died, maybe that's a sign!)

 

[jeverett]

I hope this is the correct forum for this post. I have an '81 Westy (non-CA version), manual transmission with 32k miles. I have the same problems as many of you with stalling and hard starting. I have recently replaced the Thermo Sensor II (the one in cylinder 3), I also replaced the fuel filter. I have run all the Bently diagnositics on the Cold Start Switch (valve) & Thermo Switch, the Air Flow Meter, and the Aux. Air Valve (this is inline from the Air Flow Meter and the Air Distributor). Although the switch on the Aux Air Valve is getting 12v and the Aux Air Valve itself testing fine, the shutter fails to close after the five minute "ignition on" test. My deduce that when the engine is cold the extra air to the Air Flow Meter makes for a good start, but when the engine is warm (and the valve stays open) the extra air leans out the mixture. This gets progressively worse as the engine continues to heat up. The final result is a very lean mixture and an engine which needs constant accelerator application to keep running. If I happen to stall or otherwise kill the engine, it won't start again until it is sufficiently cold that the extra air isn't leaning out the mixture too much. Has anyone else checked out their Aux Air Valve?

 

[Capt. Mike]

The AAR is subject to plenty of abuse and no maintenance. The rotary gate valve is rather delicate but isn't necessarily the freshly filtered since it is also in the decel airstream. It wouldn't take too much contamination to make it stick.

The heating coil gets fired up most every time you start the engine; that's lots of heating up of a little tiny wire. And it moves a rather fragile bimetal spring that can eventually take a permanent warp or crack.

Unfortunately, the way the AAR is constructed pretty much precludes taking it apart and replacing individual components. Since your coil and power have already been checked, perhaps some gentle compressed air and an electrical cleaner/lubricant (from the electronic shop -- not the auto shop) to see if can be freed up. It pivots on a pin that could have become corroded.

At the age of your system, a failure is not out of the question. And you've already checked out all of the other obvious parts of the FI system. You might be able to confirm the 'lean' symptom by checking plugs. Unfortunately, the FI and exhausts now scrub so well, you can't tell much by exhaust smoke which would lean towards white if too lean. but that's probably redundent if you can see the valve and have confirmed it doesn't close.

I only checked one aftermarket vendor and they were only a few bucks cheaper than VW OE, so I'd probably go the extra at VW for the warranty.

Lots of luck and thanks for a well planned and prepared post. "My VW quit; what's wrong?" is a little tough to answer.

 

[Capt. Mike]

Transferred from another post to consolidate same topics.

Engine starts momentarily then dies

zack Junior Member # 2402 posted 09-26-2001 10:29 PM

This morning my 1977 started fine. there was some bogging when i tried to accelerate. then i parked my car for work for about 10 hours, when i came out i cranked the engine over and it started and died. it starts for about a second then dies. any help would be appreciated, this is my 3rd vw but first type 4 engine so i am not to familiar with them. thanks \ vwbus1978@hotmail.com

nosliwmit Member # 267 posted 09-27-2001 03:32 PM

A similar problem with a boat I used to own turned out to be due to a clogged fuel filter... The engine would idle ok but died if I tried to give it any more gas.

 

[Capt. Mike]

A '77 is fuel injected so has a cold-start system. Often an engine will 'start' but can't continue to run because the engine isn't getting the right air-fuel ratio for that temperature, or isn't changing into running mode. Checking the FI system is covered thoroughly in the Bentley and there is a good troubleshooting chart posted on the tech drawings link from the home page.

Fuel 'delivery' to the FI problems belong on another forum.

 

[dd00]

Where to start??? My 82 Westy is air cooled with electronic ignition, FI, manual tranny, 129k miles. Engine stalls out totally randomly, sometimes at freeway speed with no warning, hesitation, or with any relation to engine temperature. I have been sucsessful restarting by simply turning the ignition on and off from 4 to 10 times and the engine will resume perfect function. This same procedure is also used to get it started after purposefull shut down (at the gas station, etc..) I know it is not fuel due to the increadibly quick response at which it will stall and restart while engine breaking at freeway speeds (ie. no coughs or hesitations, just full power or nothing).

Hopefully someone has had this type of experience, and knows how to solve the problem.
Thanks
dave

 

[Capt. Mike]

When the system will 'restart perfectly' on a random basis, it means you have sensor or electrical circuit that is malfunctioning and not resetting.

Do NOT rule out fuel supply as something like a faulty ground can cause a fuel pump to shut off until the next bump or jiggle reconnects it.

There are few sensors in an '82 AFC system that suddenly shut off the system and will then restart without waiting for a cool-down phase. Ditto the coil and ignition side, though power to the coil, (term #15) and signal to the ignition/ECU system (term #1) would do it. It doesn't have the sophisticated Vanagon Sydrome processors or circuitry. Most ECU's don't fail completely random.

I strongly suspect an electrical breakdown where either a power supply or ground is becoming intermittent. There is NO short-cut to a slow & methodical check with a sensative volt-ohmmeter. Most ground breaks will show higher resistance even when in their 'working' condition. A test light along is insufficient. This is a basic follow through of the wiring diagram.

"Jump" some of the circuits to see if they fail when supplied independently. Use appropriate caution to be sure your temporary leads are insulated and firmly attached during any tests.

 

[Capt. Mike]

Transferred to consolidate similar topics.

Curious Cold Start Valve

freakeni Junior Member # 2584 posted 11-11-2001 06:53 AM

I'm currently driving through Germany with my 81 manual aircooled gas driven Westy Vanagon.

Symptoms: Extremely hard to start cold, bucking and surging on the highway, stalls with smell of fuel in the air occasionally, uses much too much fuel.

A whileback I took out my Cold Start Vale (csv) at the request of my mechanic (he didnt even need to look at it...thanks Mech) and I've now discovered I damaged the gasket replacing it.

Ok, so I have ordered this from mw Hamburg VW dealer (poor man, perplexed by this US model . . . took ages to find the part on his CPU).

I'm hoping this will solve the problem, but NATURALLY it could be anything from fuel pump to temperature sensors (having just read the similar symptoms and outcomes in this forum).

However, let me ask this dumbass question . . . what would happen if I by-passed the csv completely? I mean, leave the sensor connected and valve in place etc, but run the fuel line over it with a tube connection?

Sure , it would be hard to start cold, but what else?

Has anyone ever tried this or is there an obvious reason (which I dont see) that makes this idea very very dumb?

Thanks for any help.

 

[Capt. Mike]

If you've damaged the gasket for the cold start valve into the distribution manifold, you will still have the air-leak, which means everything is running lean. Lean running will tax the FI system's ability to compensate. Lean combustion can cause engine damage if excessive.

If you 'jump' the CSV, remember the splice must handle a fuel pressure >36 psi -- & a leak can lead to fire.

 

[Capt. Mike]

Transferred to consolidate same topics.

Engine stalls out after 5-6 seconds . . .

mattyho Junior Member # 3394 posted 02-16-2002 06:45 PM

Hope this is the right ofrum to be asking under...I just recently bought my first Westy, a 1980 aircooled. I've been trying to get it started, and it will, but will only run for 5-6 seconds before stalling/dying on me. But, for those 5-6 seconds, the engine sounds great! I found one leaky hose from what I believe is the oil breather and replaced it, but no luck. Any help would be greatly appreciated!

 

[Capt. Mike]

Your problem could be lack of fuel delivery, which is covered under the FUEL SYSTEM, IGNITION forum or a failure of the electronic part of the FI system. Per Message Board Guideline #3, what have you checked first? Do a fuel delivery test per the Bentley 20.7 to see if fuel is getting to the FI system. If so, then do the FI system checks indicated under 24.2-17.

 

[tkhaz]

I've got an 87 Westy that starts great, runs for a minute or two, then begins running very rich and emits smoke from the exhaust before stalling out and dying. The problem disappears if I reset the system by turning the ignition off and then immediately restarting. About a minute later, the same thing happens. This occurs whether the engine is cold or hot.

Fuel delivery is good from the pump and at the injectors. The air intake sensor checks OK per the Bentley VOM tests. The O2 sensor was replaced about 20K miles back. The idle stabilizer hums away happily. The wiring harness to the air intake sensor has the Vanagon Syndrome fix and seems to check OK with a meter.

After reading through every post I can find here, I haven't heard anyone with the exact same problem. After checking things today, disconnecting and reconnecting things, I thought I had it licked when I ran it without the O2 sensor cable connected. For some reason, it idled great for probably 10 minutes and revved as it should, no smoke or dying. I thought I had an easy fix with a new sensor but was disappointed when I let things cool off for a few hours and then ran it tonight. Same problem as before. But why did it fix itself for a short time? Also, it seemed to idle happily if I disconnected the air intake sensor wiring harness. It wouldn't rev but it smoothed out the idle. Might I have an air intake sensor that tests OK but really isn't?

Tonight I went for the throttle switch. It tested positive for continuity at full throttle, but nothing at the idle setting. I am unable to adjust anything per the book because it seems that the eccentric screw #3 is missing entirely. There's a hole but no screw. #2 screw is locked down tight. Maybe it's an obvious answer but I'm wondering if the throttle switch is the problem. Would a faulty switch ever idle correctly? Mine does for some short period of time and the problem will always correct itself for a brief time when I reset the system with a restart. I don't know if a bad throttle switch would reset itself like that or would it always be bad no matter what the computer was doing.

I'd be happy to replace the throttle switch (it could be the original with 213,000 miles) but I don't want to go through a trial and error process if I can help it and someone has a better explanation for the symptoms I'm experiencing.

Thanks in advance.
-Tom

 

[Capt. Mike]

C Oda: Many models had a similar connection for a now-discontinued VW special diagnositic tool. Most had the connector wire-tied to the altnernator. It should be capped; use an old master cylinder plug or something similar. The O² sensor also used a similar connection on the left side of the engine. Use the color-coding of the wiring diagrams to isolate the connection for proper ID.

Without knowing what the other two hoses lead to, I can't comment on the 3-way T fitting.

Yes; the idle stabilizer controls ignition advance. Failure can cause the engine to be difficult to start, not start, misfire or stall. Also understand that if the ignition does not advance as designed, you run into the risk of damaging the engine when combustion occurs during the wrong part of the power stroke. FI is an interdependent system -- if one part fails or is sabatoged, the ECU may try to compensate, compounding the problem. Ignition being off, the entire air-fuel ratio gets off and things like the O² sensor are now trying to compensate.

tkhaz: These are classic Vanagon Syndrome symptoms. See the Vanagon Syndrome topic posted this forum.

 

[littlegreen]

Cold start?1?!
Our '89 Westy has recently stopped cold starting without a nudge of the throttle. She requires the throttle to be depressed slightly and she idles rough until she is up to temp. Up here in Maine I'd like to fix her myself. Any advice what to replace/check.
Thanks
Dan