Hi Friends,
Just completed a beautiful AAZ rebuild. New everything except the block. Got it all timed up and started my break-in. Unfortunately, right from first start the van never idles on its own. It requires holding the pedal down slightly. At first I thought this was just a symptom of the break-in and the parts needing to mate.
Main Problem: After 800km of break-in the engine still does not idle on its own. The engine that blew-up in my Vanagon was also an AAZ. It was however a 1.6/1.9 hybrid. It had the fuel pump from a '95 Jetta TD; thee last year of AAZ. So the pump doesn't actually move in the bracket like all the other ones. It is static timed by moving the sprocket along three channels (vs. three bolt holes like the other ones). It made it more difficult to do as there is little instruction on this style of pump. Anyway, once this engine blew up I went to rebuild another AAZ I had to put in the Van. It's pump was from a '93 Passat and is the ECO style pump without the LDA/Boost Pin. So needless to say I used the '95 Jetta pump from the engine that blew up. There was no damage to the pump; all lower crank bearing.
The new engine has the block from the '93 Passat with everything new (head, turbo, pistons, rings, bearings, etc) and the '95 Jetta pump from the damaged engine.
Here is where it get's interesting (Image below to help),
- AFAIK two shafts on the back of the pump; one for cold start at the bottom and one for idle-adjust slightly above the other one towards the top of the pump.
- The '93 pump had a vacuum actuator for increased idle when the A/C is on. This actuator controlled a wire that pulls the swing-looking lever that is attached to idle-adjust lever.
This lever had a spring; creating return-tension on the swing-lever (I'm not sure if that has any significance.
- On the '95 pump this lever was with
NO spring and had a straw-sized shaft with a spring loaded mounting point attached to the lever instead of the A/C actuator.
- This shaft extended down to the cold start lever (For cars with no A/C). My research indicates that the shaft was suppose to attach to the cold start mechanism and the two worked in concert. For whatever reason this shaft from the idle-adjust to the cold start mechanism was disconnected when I pulled the pump off the engine. I'm not sure if that has any significance.
- I cannabalised this A/C actuator from the '93 pump to the '95 pump so I can hook it up to my air-conditioning system (yes, I have the N-valves and relay); I have not hooked it up yet. This shouldn't affect anything because the natural state of this actuator is off.
Now I've seen diagrams of the different adjusting screws on the back of the pump for max/min and idle-adjust. However, I did not mess with these screws at all and the '95 pump idled just fine in the old engine. But I did cannabalise the actuator. So what did I screw up when I did this transition? How can I fix it while keeping the A/C actuator AND the '95 pump?
Any and all advice, help, scoldings are more than welcomed. Thank you!
Topic: 1.9TD AAZ Vanagon. Won't Idle. (Read 2560 times)
