Problems with Vanagon Overfueling-Poor Running

[Aynsley]

Hi All,
My names Scott, and I'm from Medway in Kent.

I'm currently experiencing problems with my Vanagon GL 2.1 MV engined Westy Camper, in that it has a serious problem with fuel consumption (just come back from the Beautiful Days Festival in Devon and it was doing approx 10 mpg!!).

Problems started last winter with a split water pipe, which resulted in revs going haywire etc, and van stalling. Pipe was replaced, as was coolant, and all bleed successfully. At the same time i replaced the 2 sensors (blue & black) as i'd never had the temp gauge working (which now works wonderfully!!).

Van runs fine on start up (smooth through rev range etc), until its put under load when at approx 3k revs it stalls, burbles and then shoots forward (once pedal is put to the floor) with much smoke and smell of petrol. I thought fuel starvation/ blockage etc, so replaced the fuel pump and fuel filter, but alas still no joy. Ive looked up Vanagon syndrome, but rather than happening sporadically, its happening every journey.

Since then I've replaced the battery, starter motor, distributor cap, rotor and leads and plugs, as well as the breather pipe (oil breather tower?), and it still misfires/ loses revs etc before it catches its breath and carries on. On one outing it cut out completely, so called the RAC, who did a few checks (they sussed starter was knackered for instance), and they reckoned the injectors were working ok (as i thought they might have been blocked).

Has anyone experienced anything similar, or knows anyone locally I can take it to please?

[jason k]

Possible lambda fault. Look at the exhaust. Find the lambda sensor. Track the wires back and unplug it. Ecu will go to a base setting. See how it drives then.

[Aynsley]

Thanks for reply.

I did think about that (have looked at previous posts etc).

Before the weekend I did try and get the Lambda sensor out (its in a stainless exhaust and not a CAT) but it was pretty solid and wouldnt budge! I did unplug the Lambda leads before coming home yesterday and revved it, but didnt really notice anything. Does the van need to be warmed up first, as i thought about that, but with all the camping gear in the back i couldnt really be bothered to unload it all at the first stop.

I'll try running with leads unplugged and see what happens.

[Aidan]

Disconnect the battery for 5 mins whilst you are disconnecting the lambda lead - you only need to sdisconnect the single wire (the signal wire) and make sure that the loom end is totally insulated and not adjacent to anything that could lead to slight voltage leak across.
Disconnecting the power causes the ECU to reset to base levels, the ECU is slightly adaptive so whilst it's been running rich it's been trying it;'s best to run clean and has adjusted it's maps to the max.
Check that the fuel regulator is getting vacuum from the plenum chamber by unplugging the hose and running a jewellers screwdriver or similar into the spigot to check that it's clear, I had a similar problem on mine caused by the spigot being gunged up so no vacuum so full fuel pressure in all situations which isn't right

[California Dreamin]

Note* I had a random 'overfuelling' issue...when it 'went' it was like the engine was on choke.....turned out to be the Lambda sensor.
Easily diagnosed as others have said...just pull the harness plug apart (hot) and the engine 'should' run without issues, plug it together again and the fault returns.
If it turns out to be the probe then.....
Be careful of 'cheap' replacements...only fit Bosch/Beru or NGK (think their lambda's are from another division called NTK)

Martin

[Aynsley]

Due to other issues (University Assignments and the Isle of Wight Scooter Rally), I wasnt able to take the van for a spin until yesterday, with the Lambda sensor unplugged.

However, it now seems that all my problems have disappeared and the van didnt miss a beat, so many thanks guys for the info and solution.

I take it I wont do any 'lasting' damage if i use the van with the sensor unplugged, at least until i get a replacement, although I dont intend to do much mileage! Then I've got a whole new issue with a severe case of galvanic corrosion as the thing is well and truly seized in, so may need some penetrating fluid or similar to help ease it out.

[California Dreamin]

Unfortunately years of extreme heat and corroding exhaust emmisions (acidic water) make this 'the norm' I'm afraid.
Best bet is a gas plant and get it nice and hot.
Your local exhaust fitter might do it for a tenner.

Martin