Loud Knocking while Driving, Need Help Options

[86motoman]

I need help. I am currently riding my bicycle to work and school until I get this fixed. That is if I can get this fixed.

1972 Porsche 914 with a 1.7

It does not make noise with the clutch in. whether sitting still or coasting, it makes no noise at all with the clutch in.

It is loudest when accelerating or decelerating. The noise is more of a low knock while accelerating, and the noise is more of a higher knock while decelerating.

The knock gets a little quieter while applying little power from the engine. That is when on a flat surface just maintaining speed it quiets up a little.

Sometimes, not all the time, the knock goes away, just for a few seconds, after taking a corner.

I wiggled the axles. This novice came to the conclusion they are still there.

I felt all of the allen bolts holding the axles against the transmission side and wheel side. They all Appeared to be snug. I emphasize the word appeared.

Any help is appreciated.

[86motoman]

QUOTE (Rand @ Jan 7 2006, 11:24 AM)

If octane was the problem, shouldn't it just be pinging on acceleration? Why would that cause a knock on deceleration?

I am not sure if it would detonate on decel and accel. Something to consider is I haven't adjusted my valves for a long time, maybe 8000 to 10,000 miles. That maybe playing a role in it.

I am not ruling out a cv joint or wheel bearing or transmission failure. The knocking reminds me of when I broke a couple of teeth on a gm ring gear, but who knows. I thought it would be best to start with eliminating the easiest suspects, detonation.

To check the axles do I need to jack the wheel up? What I did is crawled under the car while it was being supported by the wheels. I pushed and pulled on the axle. I believe I went side by side as well, but I should recheck that.