200 10V stumbles, poor mileage

[Konstantine Bogach]

Thank you.  I will figure out looking at wiring diagram, if I stare long 
enough :)

On 12/22/2009 08:59 PM, David Michael wrote:
>
> Hi Konstantine - See my replies below:
> Dave
> On Mon, Dec 21, 2009 at 4:34 PM, Konstantine Bogach 
> <kbogach at comcast.net <mailto:kbogach at comcast.net>> wrote:
>
>     Dave, thank you very much for such detailed response.
>      Can you explain in more details on how to do the measurement in
>     your item 2?  Which points to hook O-scope to?
>
> ==>I made a harness that plugged in between the distributor and coil, 
> and that harness had bare leads on it that I used to connect the 
> o-scope. You could also use "back probes" to connect to the connector 
> pins at either the dizzy or coil. I can't remember which lead is the 
> Hall output - you'll have to check the Bentley.
>
>     Duty cycle sweep is same as before, maybe a little wider (35-65).
>     Air meter plate is always a suspect because you can't see it.  Can
>     I reach it through air filter box?
>
> ==>You cannot get to the roller bearing easily, but maybe at an angle- 
> but it makes it easy to check to see  if the plate is moving smoothly. 
> You want to do it both with no fuel pressure and with the fuel pump 
> energized (only do the latter briefly, otherwise you will fill the 
> engine with gas ;-)  )
>
>     Can coil be bad even resistance test is good?
>
> ==>They can go bad when hot?
>
>     Need to check air cleaner too.   I have no garage and have to wait
>     next weekend - I need at least daylight if not warm weather.
>
>     Thank you.
>     Konstanine.
>
>
>     On 12/19/2009 10:50 PM, David Michael wrote:
>
>         Konstantine,
>         On and off I have had several bouts of fixing my poorly
>         running 200 10V. Some of the issues it sounds like you are
>         familiar with, but here are some things I learned:
>         1. Air leaks. Double, then triple check. Use Scott M's site as
>         a guide for where to look.  Injector seals, valve cover
>         gasket, rubber "igloo" and intake hose clamps all good places
>         to look. All are easy except for the injector seals..
>         2. I fought a poor drive ability problem for very long time
>         before I found that the Hall Sensor in the distributor was
>         sending false signals. I finally found that when I hooked an
>         O-scope up between the distributor and coil, and found there
>         were random "ghost signals" inter-spaced with the sine wave.
>         New dizzy fixed a world of problems.
>         3. When you set your idle mixture duty cycle, make sure you
>         also set the  idle valve control current with the bypass air
>         screw. It's best if you have two meters - one for the mixture
>         duty cycle and one for the bypass valve current. If you cannot
>         set the idle air valve it to 430MA, look for the reason why......
>         How steady is the duty cycle at idle? It should not swing by
>         more than about 30%
>         4. I had a very strange problem where my control pressure
>         regulator was not constant - it would randomly change the
>         control pressure by ~5psi. But that affected the part throttle
>         accelerating, not idle. New WUR fixed that.
>         5. Make sure your air meter flapper plate moves without
>         binding - there is a roller bearing under the fuel distributor
>         plunger, and mine was occasionally sticking.  I fixed it by
>         spraying some  lubricant through the idle mixture setting
>         hole. You have to bend the tip of the lubricant can little red
>         hose at 90 degrees to do this. It would be better to remove
>         the fuel distributor from the AFM but that is a PIA.
>         6. You need to find out if your car is hard to start because
>         there is too much fuel or too little. I did have  a drippy
>         injector once, and it would cause hard starting after 15
>         minutes - but you could also smell gas. It also had no affect
>         on idle.
>         7. Other things I have done that may or may not have helped:
>         New coil, new plugs, new TDC sensor, new air cleaner
>         Good luck
>         Dave
>         90 200 qa 240k
>
>
>