Start/restart or stalling problems


jake_beaulieu

New member
UPDATE 3: ROUGH IDLE WHEN COLD
1982 air cooled Westy

Ah ha! I have finally nailed this problem. After all the sophisticated trouble shooting with the multimeter it turns out all I needed was a can of carb cleaner. I sprayed every gasket and hose in the engine with carb cleaner while the vehicle was running. When I hit the intake manifold gasket the idle immediately shot up. I replaced the gasket (and the injector seals while I was down there) and now it runs like a top. Thanks for the pointers Capt. Mike.

Jake

jake
jake_beaulieu@yahoo.com
 

icarus

Moderator
I'm not sure if this is the right thread,,, but,

I have a '86 syncro with 105,000 miles. For the last several months it has developed a peculiar problem. Every once in a while starting off, the engine will just die. It won't stall completely, but just run at idle power. Quickly shutting off the key and turning it back on seems to "re-set" something and it runs fine. Occasionaly I have to "re-set" a few times. The first time this happened I was just running down the road, fully warm. Every other time it does it after a cold start. At first I thought it was temprature related beacause it was -20c. but after that it seems to do it at random, ergardless of outside temp. The only other clue I have is the two times I have washed the car at the self serve car was (removing road sand and salt) I had to "re-set" several times. Once the car was warm it ran fine. Each time once the car runs fine it will be fine for long trips, never a hiccough! Sometimes the car will go for weeks without doing this, so tracking the problems is difficult

I switched the ecu with a spare on the recomendation of my guru, but no avail. Other than these symptoms everything is fine. Good fuel mileage, good power no complaints. It is more of an irritant, and of course the worry of will it quite entirely? (I also have the wiring harness fix installed, but haven't traded it for another.)

Any suggestions as to where to start? Thanks


Icarus
 

Capt. Mike

Moderator
The throttle valve switch on Digifant vehicles, part #025-906-011A, is susceptible to water damage. Although generally protected (sits top right of engine) from road splash, washing engines and underchassis may get it wet. Bentley 24.58. It may just be poor contact of the electrical connector.
 

icarus

Moderator
Thanks for you advice.

I removed and inspected all the plugs. The only one that showed any moisture was the plug for the crank case breather switch. Since my problem is so intermitent, I guess I will have to wait to see if I have cured anything.

Any other advice?

Thanks

Icarus
 

ronwolffjr

New member
Any deductions regarding 'warm starts'? I have read this string several times and have yet to figure out what causes this issue - which seems common in Vanagons as well:

1976 Bus starts and runs beautifully.

After 20 miles to about 150 miles, if I attempt to start the motor again (say after sitting for 15 mins) it takes many many cranks and some gas pedal jiggling to get it running.

Once running, it's like a dream.

Curiously enough, fuel stations do not have this effect on the VW.

I believe this is so because the motor does not have enough time to cool to that 'critical point' where it stubbornly will not start easily.

I have diagnosed just about everything in the AFC system, and this one does stump me. Is there a part similar in mid-70's buses that show up in Vanagons (V. syndrome aside) that would create this situation?

Thermo-time switch tests OK.

The limited tests I can do (per Bentley) on the Aux. air valve seem to fly through.

The #3 temp sensor is new and resistance is fine.

To sum up: Why do these vehicles (w/out Vanagon sydrome) have these similar reactions? Reading the strings has not provided me with a concrete 'culprit'.

Any suggestions, or "cure experiences" would be greatly appreciated.

Thanks very much.
 

Capt. Mike

Moderator
The most logical still seem to be the cold-start valve Bentley 10-4.2 or the double relay, 10-4.1. Failure when cold is obvious, but conversly, if the valve is leaky, or working when warm and it shouldn't be, it causes flooding of the engine which is equally hard to start.
 

Capt. Mike

Moderator
Transferred to consolidate same topic.

andy b. Junior Member Posted February 24, 2005 09:59 AM

I read on a website about "The Ultimate Fix"
It helps with stalling, idle problems and power. So I gave it a try and it has worked great! I simply replaced all ground straps(engine to engine compartment, Trans to frame, and battery to frame) be sure to sand off the paint and dirt. I also cleaned and reconnected all the ground connections on the drivers side cylinder head. Besure to clean all connection well. I found replace ment straps at my local Napa store.

My van has never run as good as it does now. The idle was a mess and low power and had starts. I wish I would ahve done this first before checking all my control units and sensors! Check it out at www.vanagonauts.com
 

Adriane

New member
Posted October 13, 2002 10:13 AM by Capt. Mike on page 2 of this topic: The idle stabilizer is meant to adjust for load.

I had a high idle on my 85 camper for the first time. I was listening to my engine as I went along, and it sounded different, (smooth but working harder) so I checked and while running in neutral, the gauge stayed right up there at about 10:00. No red light. Previously, we leaned toward a low idle in neutral. I am curious about the theory behind load adjustment. I was driving home from the UPS where I dropped off my former 95 pound Westy transmission that was been sitting in the cabin for oh, 7 months. Could the idle sensor still be running from the trip with pressure appropriate to that extra hundred pounds? I would be very interested to know, and a lot of us probably carry around extra weight at times. I'm turning to Bentley and further posts for the full possibilities and tests, but I was wondering if its functioning correctly, if the fluids move around after a bit to accomodate the load? If the right chapter, post, or website explains the process I'd be happy to follow through on the research on my own with some direction, and share what I find here! Thank you~ Adriane
 

Mutz

New member
To question originally posted by tkhaz August 2001 page 1:

I had the same problem on startup when cold, ran a little rough and smokey. (88 westy 2x4) The throttle switch had no continuity at idle. #3 eccentric screw was there but adjustment did not provide continuity. I removed the throttle body and managed to bend the switchs arm with needlenose pliers saving the $115 canadian for a new switch (we'll see how long it lasts). I now have continuity at full throttle and idle and the problem has gone away. If you want to do a quick check of throttle switch, you can hear it click at full throttle and idle. When it clicks, you have continuity. I believe a new switch comes complete with ecentric screw.
 

Capt. Mike

Moderator
Adrianne -- May 9 post:

Sorry, must have missed your post earlier. No, the "Load Adjustment" of this FI system switch means "load" on the engine related to throttle setting, any hills, altitude above sea level, etc. i.e. how hard it works. It does not refer to any direct adjustment for weight beyond the work load difference to move the total vehicle such as between an empty or fully loaded vehcile. Not just a 100# or so. It would have nothing to do with a cargo's weight distrubtion or liquids.
 

Buttercup_81

New member
I am a college student w/ an '81 CA Air-cooled Westy. I recently replaced the fuel filter and O2 sensor. Here's the prob:
She starts up fine, but to keep her idling I need to press on the accelerator. In first gear, she doesn't respond to the accelerator. At a stoplight I have to do a few tricks to keep her going(pushing the brake/gas and pulling the e-brake to stay motionless while keeping her at idle w/the gas) If she stalls, she starts up immediately but needs the pedal pressed to stay running.

How can I fix this problem? I have a Bentley, but do not even know where to begin.

THank you, friends.

Shannon

PS Spark plugs are a powdered white color. She runs fine as long as she doesn't have to stop.
 

treejay

New member
howdy folks. I need help diagnosing my starting problem. I have a 1983 1.9L waterboxer. One day (about a week ago), it just quit starting. Here's what I've done:

- the starter turns fine

- battery is good

- fuel pump delivers fuel to the fuel line

- spark exists

I don't know where to proceed from here.

A friend who is a much more experienced mechanic than myself, suggested testing the relays (Bentley 24.32) To do this it says "remove all electrical plugs at fuel injectors". how does it affect the test if the plugs are left alone?

- I checked to see if their was voltage at the electrical plugs at the fuel injectors (Bentley 24.26). Bentley says "test light must flicker". Instead of a "flicker", I experienced a continuously lit test light. Does this indicate a problem or is this acceptable?

I didn't want to take out the actual injectors to check for spray pattern because I don't have new sealing rings.

Anybody have any insight to help? thanks so much in advance.

ej
 

Capt. Mike

Moderator
If you are going to try to defeat the testing procedure, the results aren't going to do much good. They are there for a reason, even if not specified. The Bentley assumes reasonable mechanical experience so doesn't try to explain everything for the novice. They may be for safety or to avoid component damage. Obviously, if they ask you to disconnect a load to isolate a circuit for testing, and you don't, the test won't tell which is defective. Also picture what is going on in your engine -- if you fill the cylinder with fuel because the injector is 'on' during tests, what happens when the engine starts? It will try to compress a liquid -- which doesn't -- and you've got fuel leaking down through the ring gaps into your crankcase, diluting oil and perhaps creating an explosive condition.

Since fuel injection seals are only about $4-5 for the whole set of 8, it's hard to have much empathy towards skipping a test. However, this is the least likely and you have not exhausted all of the other FI tests. That the electrical injector firing test failed, indicates your problems are upstream of the injector. "Flickering" indicates the injector is going on & off with the ignition stroke as intended; steady means you are pumping in fuel all the time.
 

treejay

New member
When I mentioned that the test light was not flickering, that was based on my observation (and a friend's as well) to the best of my ability. The light could have possibly been flickering at a fast rate that I couldn't distinguish. do you know if this flickering is supposed to be relatively slow or fast?

And assuming that the test light was continuous, and not flickering (which indicates continous injection of fuel), do you have a reccomendation as to where to look next? I will try testing the relays per Bentley. I don't know where else to look.
 

Capt. Mike

Moderator
I don't have Bosch specs at hand, but another manufacturer specifies their starters turn the flywheel 200 rpm, which sounds about right. The 4-cycle engine only fires every other cycle so the injector would trigger about 100 times per minute. This on-off of current should be very distinct from a continuous steady voltage. Although the test uses a test light for convenience, you could also us a multimeter and monitor the current flow on the dial or digital read-out.

I can empathize with a FI problem, but there is no magic trick or single place to look. FI diagnosis requires a laborious, step-by-step troubleshooting procedure in sequence. The how-to's are quite clearly outlined in the factory shop manual and there are no shortcuts. Bentley 24.18-24.21 just starts the process. Elsewhere in this forum are references to other publications and resources such as the Bosch Fuel Injection and Engine Management, available via at many sources including the site bookstore at Amazon.com. See the "Fuel Injection Troubleshooting . . ." topic. Unfortunately, there are a number of mechanics and shops that use the "throw new parts at it" theory until one fixes it. I'd rather pay up front for competent diagnosis than for parts I don't need.
 

treejay

New member
Originally posted by Capt. Mike:
I don't have Bosch specs at hand, but another manufacturer specifies their starters turn the flywheel 200 rpm, which sounds about right. The 4-cycle engine only fires every other cycle so the injector would trigger about 100 times per minute.
Since it is a 4-stroke engine, shouldn't the injector trigger only during the intake stroke, or 25% or the time?

I can empathize with a FI problem, but there is no magic trick or single place to look. FI diagnosis requires a laborious, step-by-step troubleshooting procedure in sequence. The how-to's are quite clearly outlined in the factory shop manual and there are no shortcuts. Bentley 24.18-24.21 just starts the process.
I'm invested in the laborious FI diagnosis process. You mention that there is an important sequence to follow yet I see no intentional flow to a process in the Bentley. And you mention that Bentley just starts the process. Do you mean that my problem might be beyond the scope of Bentley and my problem might not be addressed in it?
 

treejay

New member
OK, after some patience and vigilance and tenacity in pursuit of resolving my problem, it turns out that the FI brain was defective. I got a replacement from a junkyard and am back on the road.

I arrived at this conclusion by deduction. My fuel injector electrical plugs weren't getting voltage. I traced the wiring diagrams to these plugs both upstream and downstream of the brain. Everything checked out well. So I deduced it was the brain and sure enough. When my suspicions were high, it really helped to take my brain and and try it in another vanagon which I knew was running well. When it didn't start that van, it was quite obvious the problem. Good times with fuel injection. thanks everyone on the board, esp. Cap. Mike for help.

ej
 

Capt. Mike

Moderator
4-stroke does not mean 4 revolutions. A stroke is the up OR down. The 1st stroke is down to create the vacuum to draw in fuel/air. This is when the injector opens to let in fuel. The 2nd stroke is up for compression of the mix. The 3rd stroke is down as the spark plug fires the mixture -- the power stroke. The 4th stroke is up to exhaust the burned gases. Then repeat. An individual FI injector only sprays once per cycle which is 2 revolutions.

The troubleshooting charts in the Bentley 'start' the process by telling you what doesn't meet specifications. You must go elsewhere in the Bentley for further instructions to diagnose, repair or replace. The Bentley will get you through most FI repairs. It does not attempt to do component repairs. Major repairable components often have a reman program; others may not be financially feasible or have sufficient demand.
 

davidaoff

New member
I own a 1990 Westfalia, 80,000 miles. At first the van would randomly die with no sputter. If driving at speed it would cut out completely for a second or two then jerk back to life. If idling it would die, but restart normally. The problem worsened and became more frequent with the van cutting out when driving at speed and would restart if I left the clutch engaged while coasting thus turning the engine over and switched the ignition switch on and off repeatedly untill it took off again. Then one day no start. After tinkering around I noticed that the van would start only when at first turning the key to on I heard, in the engine compartment, a click of a relay, a second of whirring, then silence. If the van didn't make these noises I simply turned the key off then on again till I heard the special sounds, then turned to start and away I went. Upon opening a little 4"x4"x1" black box in the engine compartment’s left side which contains two relays I decided the culprit was possibly one of these 2 relays as they seemed to be the cause of the much desired click and whirr. Ordered 2 of these little relays, stuck them in their respective slots, and the van hasn't ran since??? Even with the old relays re-installed the van won't start??? Checked every fuse I could find, maybe I missed one??? Any ideas? Thanks for your time.
 

Capt. Mike

Moderator
One of those relays is the fuel pump relay; the other the Digifant Control Unit relay. Relays typically work or don't work; not intermittent. I'm guessing you already had an intermittent bad connection, ground or short and your replacing the relays made it permanent.

Wiring diagram of the relays Bentley 97.124; testing relays 20.29; troubleshooting FI 24.61-62.
 

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