[T3] EVER SO SLIGHT SURGING...

[Jim Adney]

On 30 Aug 2019 at 13:45, B Fye wrote:

> If I hold the throttle at a steady speed on the roadway, any gear, I get
> this ever so slight pulsing/surging in the car.  I can feel it, but it
> isn't enough to impact speedo readings.  It is that slight.  Load, no load,
> down hill, uphill all the same result....  any ideas guys?  Timing is
> moving correctly on the distributor, points aren't burnt, overall timing is
> 30btdc.

Is this the max mech advance achieved at high rpm? Surely you're not 
setting it there at idle. If so, that would be a big problem.

This is a '70 something, FI car, right?

A couple things to check:

1) Unplug the TPS (Throttle Position Switch) if the problem goes away, those 
contacts are worn and the only long term solution is replacement.

2) Check to make sure the air cleaner is not overfilled with oil. There's a step 
inside the air cleaner body. Fill it just to the top of that step. Never turn the 
top half of the air cleaner upside down when you're working on the bottom 
half. Set it rigthside up on something clean.

3) Tire balance? I know this is a long shot, but it might be confused with your 
symptoms. If so, it must be rears, because you'd feel a front wheel balance 
problem in the steering wheel.

> Any chance i could have a clutch not quite 100% engaged?

Always a good idea to check the clutch free play, but that's not likely to be 
your problem. You can test this by flooring it in top gear. If it's going to slip 
any time, that's when it will slip.

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Jim Adney, jadney at vwtype3.org
Madison, Wisconsin, USA
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