2.1 petrol running issue

[lambrettalee]

My 2.1 petrol (mv code,digifant) has started misbehaving on petrol ..on lpg it runs fine.It starts and idles 1st turn of the key, when pulling away there is a massive dip between gear changes and it feels lumpy at low revs as if its going to cut out but doesnt actually do it,it feels slightly under powered also. I have been round and cleaned all connections,disconnecting the lambda sensor made no difference at all but unplugging the temp sensor in the thermostat housing made the revs increase at idle to approx 1400 rpm but it drove without any issues..Have I hit the nail on the head and it needs a new sensor or is it purely overfueling and masking the real problem ?

[itchyfeet]

All of the Vanagons that were ever sold here were fuel injected. The Air Cooled used a version of the L-Jetronic system the 1.9l Vanagon used the Digijet system and the 2.1l Vanagon used the Digifant system. I am so well versed in all of them that I can usually tell people what their problem in within a 5 minute phone conversation. After working on the same car for 16 years, your Spidey Sense start tingling and you can figure it out pretty quick. I would be lost working on carb systems. I have done a few but I didn't grow up with them like many of the older VW mechanics here in the US. The old Beetle guys hate FI and love their carbs. I am the opposite. It is just what you are used to. Here in the US because of emissions they started putting Fuel Injection on the VW bus in the mid 70s and also on many other VWs including the Beetle. I was born in 74 into the age of FI.

Looks like kens your man

[lambrettalee]

Ken Dodd??

[itchyfeet]

http://forum.club8090.co.uk/viewtopic.php?f=10&t=129470" onclick="window.open(this.href);return false;

Its only an air fare

[lambrettalee]

http://forum.club8090.co.uk/viewtopic.php?f=10&t=129470

Its only an air fare

I will start with the coolant sensor then maybe a KENtucky fried chicken to celebrate if correct

[mark]

are you unplugging it when its up to temp? if yes then it sounds like the culprit. also search stabilisation

mark

[lambrettalee]

Yes I am .. Unplug. re start, revs increase then idle drops to 1400 .. Then drives ok ..