1984 Jetta , TDI WE MUST! (1.9 AHU M-TDI)

[R.O.R-2.0]

Libby, If I have an early 82 or late 81 IP does it have that hole?  I really don't remember it when I took my pump apart about a year or more ago. 

Being that it is just under the cover I suppose I could get to it with less trouble than more but won't do that if there isn't one in the first place.

EVERY BOSCH VE pump has that feature.. no matter the age..

[libbydiesel]

Nope, most of the 1.6 pumps don't, but I've seen a few that did.  The telltale sign is if there is a ball bearing blocking a hole drilled into the surface just above the governor nut, right behind the timing pointer).  If the ball bearing is not present and there isn't a fitting there like on the AAZ pumps, then it does not have load dependent timing advance and the position of the governor shaft is not critical.  

[ORCoaster]

Awesome,  I can look and not even touch and determine this one.  I do have a 1.6 NA engine and the car build date was August of 81.  So it has some but not all the features of an 82.  Another couple of months and I bet I would have had the upshift light and W terminal combo.  I can see the arrow on the dash but there is no bulb or socket behind it. 

That is the answer I needed.  And my memory is as good as I remember it.  quote that. 

[8v-of-fury]

Alright so Thursday I took the pump back off the engine and tore it back down to make sure I had not done something wrong inside in terms of clearancing for the modified lever. I only had time on Thursday to dismantle the pump and verify with another open stock pump that I had in fact clearanced everything correctly, and it was moving freely inside.

I was then away all weekend, so tonight I got the pump together, back on the car and running within the hour. From there I messed with the fuel screw and idle screw. I had the fuel screw backed all the way out so that it was just pushing on the arm of the internal throttle. I also had the idle screw backed all the way out, so that the external throttle was just resting on it. I got the car running and idling, but it did seem that the idle was completely erratic and seemingly uncontrollable.

The idle almost seems to hang like it does to people after they have done the governor mod. I had the external throttle lever indexed so that it would be the same every time, but using that mark i could not get low enough on the idle. Even having both the throttle stop screw and fuel screw backed all the way out. So I moved the throttle one spline over to release tension on the governor cage. Now I have a lower idle but it is uncontrollable. It is either idling like 13-1400 or it idles so low when i put the clutch in that it stalls.

[libbydiesel]

You've done enough swapping that I can't keep track.  What spring setup did you use?  The assembly on the left doesn't have an idle spring installed on it.

As far as your idle symptoms, it sounds like your idle spring is too weak.  When it is too high, the idle spring is at the collapsed and you are engaging the main/intermediate spring part of the capsule.  I have seen that before on a used Cummins pump.  I pulled the spring and stretched it out a bit, reinstalled it and voila, idle was @ 850 with room for adjustment.    

[8v-of-fury]

Lol, Andrew sorry man. Yes I agree I can't even keep track of my own shizz.

I used the setup on the right. It is an AAZ governor cage with the idle screw added, inside a 1.6 throttle shaft. So I did not have to wrestle the e-clip back off the solid governor one. It is a stock 1.6 idle spring on my governor assembly. Interesting, so you think the spring being too weak is a good candidate for the symptoms eh? Hmm, it ran the pump just fine before the modified internal throttle though??

[libbydiesel]

The following is just conjecture on my part.  You changed the lever assembly and altered the fulcrum significantly.  That will change all the spring ratios.  The governor assembly will now be pushing closer to the fulcrum on the assembly and so any motion of the governor will have an increased impact on fueling and could account for the idle spring now being out of range. 

[8v-of-fury]

So as it would seem the stock wastegate was really holding back.. Today i got the pump back together for the 6th or 7th time! Various issues with the modified lever binding up and not acting the way we wanted.. I had a sputtering issue that prompted thevlast tear shown of the pump, and as it would turn out there was some snarff that was in the high pressure pickup.. but it was not the reason of the sputter. It would seem theorizing was retarded and thus causing too low pressure at higher rpm, making a sputter.

i also dissconnected the waste gate to see if the boost was holding back the power to 10Psi or so.. it totally was! Not even pushing the peddle now causes the boost lines to blow off!!!! so gauges and my manual boost controller are next!!

[8v-of-fury]

10mm distributor head timing gauge adapter A drilled out and tapped oil pressure sensor.

[8v-of-fury]

So with that gauge adapter in my last post I finally remembered I made it today and went to check my timing for ***s and giggles. Its running great, but i figured why not since when I initially set it back in March/April it was by ear.

As it would turn out.. the pump was timed to, are you ready for it?? 0.083" or 2.108mm! JESUS. How was it even running? and so well!?

I have since re-timed the pump down to a more conservative 0.050-0.053", and I must say.. I am down on power and there almost seems to be a miss.. Interesting it ran so well with the timing that jacked up.

[CRSMP5]

i have my disco set to 118... so try that.. others w discos say 135ish..

[8v-of-fury]

I set it somewhere between 1.30 and 1.35. It was missing a bit, smoking and down on power. So i loosened the pump, started it up and tapped it advanced a bit more. So I am sure I am at 1.40-1.45 easily.

Weird eh?

[8v-of-fury]

I mean I had it at 2.10mm!!! and it ran great.. but then i got to reading about how the cylinder pressures at this point would be ridiculous.

[libbydiesel]

I have found that they run best with start of injection at 12-13° BTDC.  Because I have a diesel pulse adapter, setting any pump to that regardless of custom internals is very easy.  Without a pulse adapter, with a non-stock pump, IMO, the best you can do is time it by ear or dyno app on a smart phone.

[8v-of-fury]

So with the pulse adapter, it simply measures cylinder #1's injection pulse through the injection lines? Nice. I assume the DI stuff would still be clacky with too much advance, am I wrong to assume this? FRom the 2.10mm setting it started, idled and ran through the rpms just fine.