Idle Control Valve

[Silverghost500]

Von Westy was running really rough today. Rough idle until she really warmed up. Had to keep my foot on the gas at stop signs and red lights.

Tried working with the idle control valve. Unplugged the white electrical connector, same rough idle. Disconnect the rubber hose going from intake to the valve. Same rough idle. Removed the valve from the rubber pipe with the white vacuum line going to it. Engine roared to life, and rpms soared to 1,500!

After reading some threads I tried spraying some carb cleaner into the valve, put all hoses and electrical connection back together. Rough idle. I tried pulling the rubber hose from the intake off and it ran a little better, but then the valve sounded like it was whistling. I could put my hand over the valve and could feel vacuum.

Do I need to try again with the carb cleaner on the valve, or should I go ahead and buy a replacement?
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1986 Volkswagen Vanagon Westfalia "Von Westy"
Honda K24A converversion-Road Testing Phase
3-Speed Automatic

Von Westy YouTube Channel
https://www.youtube.com/channel/UCbhyZYxJEQrUuLnMbLleeIA

[0to60in6min]

it could be the ICU and not the ICV..

https://www.vancafe.com/251907393DX-p/251907393dx.htm

I would suggest borrowing an ICU and try before replacing the ICV, because the ICU is more fragile (electronics) than the ICV which is just a mechanical air pump.

[Silverghost500]

It's possible it's the control unit. I pulled the right taillight out late last night, but didn't have time to really reach in and get to the module. Unfortunately I don't know anyone close by to me that has a working spare I could use to test with. That, and if there was another fault I'd had to impact someone's known working unit.
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1986 Volkswagen Vanagon Westfalia "Von Westy"
Honda K24A converversion-Road Testing Phase
3-Speed Automatic

Von Westy YouTube Channel
https://www.youtube.com/channel/UCbhyZYxJEQrUuLnMbLleeIA

[0to60in6min]

Since you already take the ICU out, you could open it and inspect it for burn component or corrosion. It's very easy, take a thin flat tip screw driver and carefully pry it out of the black box.. if you smell burn component it's not good even there's no visual sign to see.

[vwoldbug]

Has the van been tuned up and compression checked lately .

[Silverghost500]

Tonight's agenda will be getting the control module out and inspected, as well as more cleaning and testing the valve with a battery and jumper wires to make sure it activates with power applied.

@vwoldbug the Westy was running this badly when I bought it a couple of weeks ago. I have installed tune-up parts (plugs, plug wires, distributor cap, rotor button) as well as put new fuel lines, and seals on fuel injectors. I've not performed a compression check. I need to pick up a tester and do that too.
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1986 Volkswagen Vanagon Westfalia "Von Westy"
Honda K24A converversion-Road Testing Phase
3-Speed Automatic

Von Westy YouTube Channel
https://www.youtube.com/channel/UCbhyZYxJEQrUuLnMbLleeIA

[Silverghost500]

Tonight I did a couple of things that might be a bit unorthodox, but hopefully they help me in getting to a final resolution.

I tried my idle valve after having it in carb cleaner spray and blew it out with air. No go. Idle was complete crap, and then the engine died. I found the idle control module, and pulled it out of it's long resting cubbyhole. That wasn't too difficult, but getting the wiring harness off of it was a bit of a hand muscle workout.

With both the idle control module and valve off I started the engine, and the rpms raced to around the 1,600 to 1,800 range. I put my hand over the intake port side where the valve goes in, and the engine wanted to die.

This is where the unorthodox part comes in to play. I looked at the two rubber hoses that connect to the idle valve. I bridged them with another piece of hose. The idle dropped down to around 1,100, and she seemed to like it there.

I decided to take her for a short ride with the bridge pipe configuration. Wow, what a difference! I could hit the gas pedal and she didn't bog. She even was able to downshift when needed, which hasn't happened since I bought her. I took her out for a little bit longer, and surprisingly I was keeping up with traffic pretty well (for a Vanagon).

It could be one, it could be both, but that idle control assembly does seem to be the culprit to all of this for mine. Not condoning running all the time with the bridge pipe, but right now I don't have the cash to drop a few hundred dollars on those components. For the little bit that I plan to drive for the next week or so it'll do in a pinch.
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1986 Volkswagen Vanagon Westfalia "Von Westy"
Honda K24A converversion-Road Testing Phase
3-Speed Automatic

Von Westy YouTube Channel
https://www.youtube.com/channel/UCbhyZYxJEQrUuLnMbLleeIA

[DanHoug]

the 'bridge pipe' connection is creating a VERY large bypass around the throttle valve. the air IS metered, so there's that going for it but you'd be better off BLOCKING both the intake manifold hole and the intake boot hole.

i've done that on my 87 and it runs great without the ICV. you have to adjust the idle speed with the large screw on the throttle body.
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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

[Silverghost500]

Thanks Dan. What did you use to block both ports?
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1986 Volkswagen Vanagon Westfalia "Von Westy"
Honda K24A converversion-Road Testing Phase
3-Speed Automatic

Von Westy YouTube Channel
https://www.youtube.com/channel/UCbhyZYxJEQrUuLnMbLleeIA

[DanHoug]

you can use anything that fits in the hole! a cork or whatever. i used the red plastic cap off of a length of threaded pipe for the boot.. i save all those plastic bits for just this sort of stuff.

the manifold connection is a piece of steel tubing sticking up so you need to either put a cork in the end of it or make a length of hose that slips over it with something stuck in the end of it like a bolt to block it off.

both connections are under negative pressure so any tapered plug will stay in... will only pop out on a backfire.
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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

[Silverghost500]

Some interesting findings from the past two days. Kept the bypass hose in between the ICV pipes and drove around that way. Cold crank idle speed was 1,100 rpm. When the engine warmed up idle climbed to 1,800 rpm. Only when blipping the throttle would it calm back down to 1,300, but as soon as I would accelerate off and start to slow down the idle speed was back up to 1,800.

Tonight I removed the bypass hose and took Dan's advise plugging both ICV hoses with corks. Idle speed was now at 400 rpm, and then stalled. Before cranking again I checked the throttle position sensor for the audible click coming off idle. It didn't click, even though it had a week or so earlier when I adjusted it cold. I decided at that moment not to adjust it again.

I decided on a whim to unplug the AFM. Engine cranked and stayed at idle around 900 rpm! The engine finally started to sound like it should at idle. I revved the engine both at the throttle body and then with the throttle pedal expecting the engine to stall, but it didn't. It revved right up, and then idle speed dropped back down to 900 rpm.

When the engine warmed up though the rpms started to climb up to about 1,300 rpm. I decided to try an experiment. Shut the engine off, unplugged the temp 2 sensor. Started the engine and while at first it was rough running it stabilized and idled back around 900-1,000 rpm range.

I stopped the engine, plugged the AFM back in and it would not crank. Only when I plugged the temp 2 sensor back in did in again. Oh, and the audible click from the TPS? Now it was back and audible when the throttle body came off idle position now that the engine was warm.

Now I'm feeling like I've discovered more parts with problems. I don't have any spare parts to swap and narrow down, which means it looks like some hefty parts orders are in the future.
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1986 Volkswagen Vanagon Westfalia "Von Westy"
Honda K24A converversion-Road Testing Phase
3-Speed Automatic

Von Westy YouTube Channel
https://www.youtube.com/channel/UCbhyZYxJEQrUuLnMbLleeIA

[CessnaJon]

FYI, I just installed a new Go Westy throttle body. I still has some deceleration bucking/kicking and a stumble just off idle. These symptoms were aggravated with the a/c turned on. I Disconnected the plug to my idle control valve an set the idle speed I wanted with the big screw on the throttle body. Wow! it runs so nice now hot or cold. No off idle stumble, no bucking on deceleration, and idles so smooth its hard to tell if its still running. So, I'm done with the Digifant idle control altogether.
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1973 Westy (shared birthday)
1990 Westy Multivan
2015 Passat TDI 6sp
2015 Sportwagon TDI 6sp
LR-JET, Gulfstream 159

[Silverghost500]

CessnaJon, are the GoWesty throttle bodies back in stock? Theirs includes a throttle position sensor too, doesn't it?
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1986 Volkswagen Vanagon Westfalia "Von Westy"
Honda K24A converversion-Road Testing Phase
3-Speed Automatic

Von Westy YouTube Channel
https://www.youtube.com/channel/UCbhyZYxJEQrUuLnMbLleeIA

[Steve Arndt]

[CessnaJon]

Yes, It comes with a new switch. It’s a really fine product. The installation of the new throttle body and disabling the icv has totally transformed my waterboxer.

We should plan an Atlanta Vanagon campout soon.
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1973 Westy (shared birthday)
1990 Westy Multivan
2015 Passat TDI 6sp
2015 Sportwagon TDI 6sp
LR-JET, Gulfstream 159

[Silverghost500]

I went ahead and got on their notification list when it's back in stock. In the mean time I've got a new temp 2 sensor on the way.

@CessnaJon-Yes we do! It'd be great if we could get some Atlanta area based Westies out for a weekend adventure.
_________________
1986 Volkswagen Vanagon Westfalia "Von Westy"
Honda K24A converversion-Road Testing Phase
3-Speed Automatic

Von Westy YouTube Channel
https://www.youtube.com/channel/UCbhyZYxJEQrUuLnMbLleeIA

[Silverghost500]

A few more things tonight and interesting results. Reset the TPS so it clicks right off idle...most of the time. I think that switch's day's are numbered. Still think I should prep for throttle body/switch replacement as a package deal.

Started her up and she ran like crap. I decided to unplug the O2 sensor. Started her up again and she was idling much better, and the exhaust didn't stink like it has been. That in itself was a good thing as last night she stunk up my basement and the whole upstairs!

Then I got the timing light out just to check and see what was going on there. Wow! I'm glad I did because she was way too far advanced! Printed off the GoWesty timing template and applied it. Revved her to 3,000 RPM and started adjusting the timing.

With that effort she was able to stay at a steady 900 rpm. I'd rev the engine at the throttle body and the pedal. Things were looking and sounding better, so I took her for a test drive.

Out on the road she was much more responsive! I was able to get on one of the long two-lane country roads and was hitting 55-60+ without too much effort. Every stop I came to idle was still at 900 rpm.

While out I decided to make part of my test run on the freeway. She was able to do 65-70 mph without fuss. As I was driving along I thought "Wow! This is what I was expecting all along!" The freeway run was about 6-7 miles long.

When I got back to my road she still dropped down to around 900 rpm, but was a loped a bit. She did stumble too at a red light, which had me concerned. I got her home and when I was waiting on the garage door to go up she died. I was able to crank her back up again and get her inside.

At least for a few moments tonight I was enjoying driving her and relaxed a bit. Looking forward to the day when that can become the norm.
_________________
1986 Volkswagen Vanagon Westfalia "Von Westy"
Honda K24A converversion-Road Testing Phase
3-Speed Automatic

Von Westy YouTube Channel
https://www.youtube.com/channel/UCbhyZYxJEQrUuLnMbLleeIA

[DanHoug]

keep in mind these are antiques and have a balanced system... EVERYTHING must be spot on for them to run right as they lack adaptive control that can cover issues.

so. clean injectors, tight high tension ignition system, no vacuum leaks, O2 sensor healthy, no exhaust leaks, good compression and clean valves.

a well sorted out vanagon engine runs just fine albiet with a somewhat lumpy idle. but it takes perserverence and some money to get it there as they are easily 30+ years old. if your oil pressure and compression are fine, the rest can be fixed pretty easily.
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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

[B.O.B.Wanders]

Sounds like you're making great progress!
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83.5 WBX 2WD Assuan Brown Westy, B.O.B.

"It feels good to be lost in the right direction” - unknown