'81 n/a pump acting funny

[tyb525]

I just got this car a few months ago, rebuilt the engine, new injector lines, yadda yadda, it's running great overall. But I've noticed this thing with the pump that is hard to describe.

In neutral, 1st or 2nd, (3rd and 4th it is harder to detect) when I slowly increase the rpm's to a certain point say 2000-2250, it's like the governor will jump up to about 2500-2750 and level off right there until I give it some more fuel. It's like the pump "wants" to jump up to a specific RPM once it gets close to it, but it doesn't go above that RPM until I tell it to. It feels like I am flooring it for a split second to get from ~2000 to ~2500. It doesn't do it in any other RPM range. If I am flooring it or accelerating pretty fast through that RPM I don't notice it.

It isn't causing any issues really and it doesn't bother me too much, in 3rd and 4th it doesn't really do it because it harder for it to speed the engine up that fast. No air bubbles in the lines, I don't know what the pump is like but it isn't leaking, rebuilt injectors, no smoke except the norm when I floor it.

My thought was it has something to do with the governor spring. Is this what it feels like when someone does the gov mod? I've never done that mod so I don't know. The PO of the car didn't seem to know much of anything about it, he bought it then realized he wasn't capable of working on the car.

[8v-of-fury]

In 1st or 2nd, if you increase revs past 3750, does it want o keep screaming towards redline? or do you  hit a wall of where the acceleration stops?

[tyb525]

I've never intentionally took it to redline because I don't know if the gov mod was done and don't want to rev it beyond what it would do stock (and I don't have a tach). Highest I've had it is 60mph in 3rd, should be around 3650rpm (with GP trans and 155/80/13 tires). I didn't try to go any faster but it seemed like I could have gone a little faster with some time.

[8v-of-fury]

If you neede time to do third past that rpm then you likely have a weak governor mod or none at all.

The pump will stop injectimg before engine damage. The pumps only go to 59-6000 or so.

[tyb525]

Ok, well that's fine by me if it isn't modded. Could a worn pump cause this? Like I said it isn't something I'm worried about, just a little quirk.

I've also noticed that if I keep the pedal in the same place, the governor will keep the car going pretty much the same speed regardless of hills, etc, unless the hill is really steep. It's kind of like cruise control. All I've driven are gassers and I'm used to adjusting the throttle to keep the same speed. I assume that's just a diesel thing?

[TylerDurden]

Very possible the IP in your car is not original. If you can post a pic of the IP & its ID numbers, it might provide some clues.  Bosch made a million types of IPs and the governors can vary (min-max, variable-speed, combination).

[tyb525]

Exactly as it looks on the side:

NR 0 460 494 077
VE R 66-8
(VAG symbol) 068 130 10/AG
011 145                16461
BOSCH Germany

Never mind the duct tape, it's to keep the accel cable from rubbing the fuel line till I can reroute it better