Used to read the 914 parts diagram catalog like a novel and thought I had it all figured out. But after seeing an old picture in the Classifieds today of an L-jet throttle body with a spring, I realized I don't have this spring.

Porsche calls it the Return Spring 022 129 881 F.

Can someone with a 1.8 L-Jet please post a picture of where this spring connects. I can see where it connects on the TB, but what about the other end? On the plenum, or body sheet metal somewhere?

Thanks,
Bryan

On my old 1.8, it connected to a hole in the rear (vertical) engine tin. I don't know if that was stock or not, though.

--DD

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I have a 1975 1.8, didn't drive it today, will take picture tonight for you

The pic that Type47 shows is the way I remember mine being.

--DD

What is the actual purpose of the long spring? It seems like it prevents the throttle from closing too quickly. The actual return spring is wrapped around the TB shaft.

Wow - Thank you! I never would have found that.

I was wondering that as well.

Mine is 75 1.8L F.I. and since I acquired this teen last 2011 it does not have that extra spring. The return coiled spring is doing his job already. I tried before installing a long return spring but it just hardened my accelerator pedal.

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probably makes it harder to push the gas pedal to prevent you from/make it a little harder to unleash all that HP factory speed limiter?

here is my '75 with 1.8, this is the way I got it, can't tell you for sure if this is correct/factory, 63k miles on it; good luck, please post what you find out

It's like the spring on the 2.0 throttle body--at least, all but the early 73s. The long coil spring is the primary return spring; the one coiled around the throttle shaft is the "supplemental return spring", and is intended to let the throttle close if the primary spring breaks.

--DD

Found this thread while reattaching the return spring on my L-Jet; After looking at the picture I see mine had been on backwards; the outer end had been attached to the plenum instead of the rear tin.

When I connect the spring to the rear tin, it pulls the arm of the throttle body back Toward the rear. So, does this add tension to the main TB spring and make the accelerator pedal harder to push ?

I believe it is a safety thing. So if the big spring breaks the little one will close the TB.

I remember reading a post where someone actually did have the big spring break. He might be the only one alive (that did not die), from not using the little spring.

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1972 1.7 tins. The hole was there from the FI days.
I’ve seen other cars using this hole. Hard to see,
the seal usually hides it.