D-jet troubleshooting, Only one item left on my list! Options

[saigon71]

My 1974 2.0 D-jet is running very strong, but there were two lingering issues with the FI that I wanted to address over the winter:

1. A severe idle "hunt." The engine would rush up to about 1200 RPM, then nearly stall...repeat cycle.

2. Every once in a while the car would buck, most notably at highway speeds...it wasn't bad, just annoying.

Last week I installed a new circuit board in the TPS purchased from Dave Sprinkle a few years back. It was calibrated according to the Pelican tech article using an ohmmeter.

I took a 210 mile road trip over the weekend to test things out. The car now idles perfectly through the entire warm-up sequence. Thanks Dave! (IMG:style_emoticons/default/beerchug.gif)

The problem is that I still have the same bucking issue. All my research points to the TPS. Any suggestions on what to check next?

[watsonrx13]

Well finally had a chance to check the vacuum advance on the distributor.

Here are the steps I took (photos to follow).

1. Removed distributor cap
2. Disconnected the vacuum hose
3. Hookup up a vacuum gauge (hand pump to bleed brakes) to vacuum advance on distributor
4. Pump up the vacuum and checked movement of arm.
5. No movement on arm
6. Hookup vacuum gauge on other line
7. Pump up vacuum and noticed movement on arm
8. Reconnected vacuum line to other side of vacuum advance (using a hose clamp)
9. Test drove car

Conclusion: the car didn't sputter, but now the idle is around 1600 RPM, before was 900 RPM.

So is this a good solution?
If this is a good solution I'll readjust the idle.

Vacuum pump hooked up to first vacuum line


Close up of connection of vacuum pump


Vacuum hose hookup to second vacuum line with extra hose clamp


Wide shot of distributor/vacuum hose connection


Vacuum pump set up


Vacuum pump kit