Itinerant Air-Cooled

So, wondering what you think this might be:

We are getting an unwanted surge of power in Drive when we first take off from a stop. It bucks and revs really high, it hesitates when you press on the gas then jerks forward. It will sometimes I've a sudden surge out of nowhere. Then after awhile it goes away, we'll drive s hundred miles with no problems, then when we stop it'll start doing it again. At stop lights, it tries to move forward intermittsntl, it'll surge then drop,surge than drop, pulling us forward. We learned to just put it in neutral at lights when this is happening. There than that, we're great. Heading to Grand Rapuds, Minnesota for a music festival.

This is an Automatic Transmission. 2.1 L Vanagon.

Many far more expert than me will answer, but have you checked your vacuum hoses for a crack? That's where I would start. A crack that is opening and closing may explain why the symptoms seem to go away for some period of time and then return. The driveability problems sound similar to what I've experienced with a vacuum leak.

jcbrock wrote:Many far more expert than me will answer,

We will? I'm late.

What year Vanagon? Dijijet or Digifant? Things we need to know. Idle stabilizer hooked up?
Colin

thejeremynix wrote:This is an Automatic Transmission. 2.1 L Vanagon.

Sorry, you're giving us slightly confusing information here.

An '82 aircooled vanagon would have a 2.0L engine stock from the factory (1970 cc, rounded up to 2.0L for marketing purposes). The later watercooled engines ('86 and newer) had 2.1L engines from the factory. The FI systems on the two engines (air- vs. water-cooled) are quite different and share virtually no parts in common.

It may very well be that you do have a 2.1L aircooled engine, but that immediately implies that someone has installed a 96mm "big-bore" piston and cylinder set, and may also have installed a "performance" cam or other "upgrades" as well in a quest for more power. If this the case and your engine is using the stock L-Jetronic fuel injection system, then you may be in the unenviable situation of having an engine that L-Jet just can't ever be happy with.

In order to be of any help at all, we'll need to know definitively whether your engine is stock or modified, and if modified, in what fashion? Also, if you are using the stock L-jet system, it would help to know if it is the Federal version or the California version.

I'm on a phone one or I'd give a more complete answer. For now I'll report that it is a transmission issue, not an engine issue. One shop says cracked torque converter.

How do I know all this, you ask. Because the OP and I are well acquainted on the facebooks.