Club 80-90 Forums

This has been going on a long while now, but I've recently come back to it as I'd like to use the van for a few moving jobs and maybe a bit of a tour next summer - and it has to get to the new place under its own power! I've read pretty much everything in the Wiki and on GoWesty, but I don't seem to be getting anywhere.

The original problem was that it wouldn't idle, and would die if you took your foot off the accelerator. Then it started running rough when warm and became a real pig to start.

Over the last few months this is what's been changed or fettled: idle computer (GoWesty refurb), idle stab valve (Brickwerks x 2 - first failed after a fairly short time), T2 sensor (twice), AFM (GoWesty refurb), throttle body (it's probably a GoWesty refurb with roller bearings on the throttle shaft, but was on the bus before I had it) plus checking idle/full throttle microswitch, dizzy, cap, rotor, leads, plugs and coil, ECU checked by Actronics, all vacuum pipes, fuel filter, O2 sensor. The timing has been set up at 7º at 2500rpm. When cold, the bus will start perfectly and idle at around 900. As it warms the idle becomes a bit erratic but generally it will now idle pretty much all day as long as it's left alone. It will also respond properly to full power-steering pump load. Hold it at 2500 rpm on the throttle when it's warm and its starts to get very erratic, sometimes almost dying and other times revving harder with no movement of the throttle. Take your foot off once it's like that, and it will almost always die rather than idle. It's then hard to start, and won't idle until it's warm again. Sometimes, as it's dying, pumping the throttle will get it to stay running, but it's not really responding to throttle input.

It doesn't smell as rich as it once did, but does if it's restarted when warm. Another trait it has is to die if the throttle is lightly pressed from idle. I can't really say what it's like on the road, as I daren't take it out!

I'm kind of left with getting the ECU checked again (I've contacted ECU Doctor already!) but are there any other ideas? The fuel tank was new about 6 years ago, and the last filter seemed ok when I checked it.

have you tried a vanagon syndrome harness ? Just that to me it's pointing at AFM signal, the parts may be fine but the signal is possibly getting lost before the ECU, trouble is it is hard to check inputs to ecu when it is running and difficult to move the flap in the afm without removing it from engine, but I'd be suspecting wiring breakdown due to heat or poor contact due to thermal expansion or vibration
IIRC I leant my vanagon harness to David krankinwagen to check out a van in Dublin

Hi Aidan. Funnily enough, I remembered that I'd got a GoWesty capacitor harness tucked away somewhere and I'm in the process of fitting it now. Bloody soldering iron's broken, so standby for news later...

Ok, Vanagon-syndrome harness fitted. No difference. I think it's got to be either the ECU or somewhere in the loom. Anyone fancy making me a new engine bay wiring loom?!

I have an MV loom in stock, same as SS I think, I'd have to check they are the same, also have spare ecu

Hi Aidan. Ok, hit me with it - how much?! And yes, the MV should be the same as SS. Even if the ECU isn't the problem, it would be good to have a spare - I used to have one years ago but sold it on this very website, I think, for about £30!

I might be stating the obvious but have you looked at your starter/solenoid? Could be jamming things up as it heats up. And all your grounds obviously.

I have the opposite problem at the moment...unable to hold idle when cold, but fine once warmed up.

Try removing the metal sheaths off the ends of the HT leads.

Humour me.

How is she running these days TimC?

Sorry, guys, been busy with other things in life and the van has had little or no attention in the last few months. However, I'm moving so I need to get it going! I've bought a new (refurbished) throttle body from GoWesty, which has their more sturdy hi/lo microswitch system, and roller butterfly bearings. It doesn't have the SS vacuum-controlled choke system, but starting from cold isn't an issue so I can live without that for now. I'm going to spend today playing with it, hence looking in here again!

Just to recap, I've now replaced the idle computer, idle control valve, AFM, throttle body, plugs, leads, dizzy cap, rotor and all vacuum pipes. I've had the ECU checked properly, and I have the GoWesty 'Vanagon Syndrome' device fitted between the AFM and the ECU. The O2 sensor and temp sensors are new. The only thing I haven't replaced is the distributor. I have a new one, but it doesn't have the TDC mark as per the original which makes it a bit hard to set up - I don't have workshop facilities; I'm doing all this on the drive. I strongly suspect that the timing isn't exactly right, so that's today's task.

danmetallic wrote:I might be stating the obvious but have you looked at your starter/solenoid? Could be jamming things up as it heats up. And all your grounds obviously.

I have the opposite problem at the moment...unable to hold idle when cold, but fine once warmed up.

I have checked and remade/replaced all the earths. I haven't played around with the starter, which is working fine, but I'll check it.

chuckle-bus-tom wrote:Try removing the metal sheaths off the ends of the HT leads.

Humour me.

Why? The leads are new, and the problem predated them.

Still playing with it. Latest change is GoWesty-refurbished ECU and new injectors and plenums. No significant difference. I'm now down to the wiring, everything else has been changed!

Just to double check have you checked the large relay block behind the off side tail light? It really does sound like a vacuum leak...have you taken the idle stabilisation valve off and check the small piece of pipe going down into the engine? That caused exactly the same issues for me.

The Idle Control Unit? Yes, that was replaced by a GoWesty remanufactured unit. Unlike in the DJ, it can't be bypassed. I have replaced all the small-bore vacuum pipes, but I will start looking through the larger bore items. I have three Idle control valves (including the original) and they all behave differently! But the essential issue of pick up and restarting when hot is the same with all three, so I agree it could well be something like that.

I've got a new O2 sensor and T2 sensor to try as well, when I next get a bit of time to play.

Further down the road.

The van had to go to the local garage (a Porsche specialist) for its MoT, so I had them look the whole thing over. It failed the MoT on a couple of things (a couple of minor chassis welds, front brakes, exhaust knackered), so I said fix it and give it me back when you're done.

Well, it's beaten them! They fitted a new Brickwerks stainless exhaust system, and a new thermostat housing with new O2 and T2 sensors. It refused to run at all until new plugs were installed, at which point it returned to the previous behaviour: perfect when cold, all emissions excellent, idles well, pulls perfectly. Get it warm, however, and it'll stall at the slightest resistance and then won't start. Just to recap, the following ignition/injection parts were replaced with new or guaranteed refurbished (mostly GoWesty or Brickwerks) parts: AFM, idle computer, ECU, throttle body, all vacuum pipes, auxiliary air valve (idle control valve), injectors, plenums, distributor, coil, leads, O2 & T2 sensors, starter motor and battery. Is that enough?

If I could get it to Simon up at Brickwerks, I would, but that's just not practical - I'm in Suffolk. Anyone know someone who's good with the 2.1 SS/MV motor in this part of the world?