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Re: 80 Turbo....hunting/erratic...at idle... Posted by Gary Stottler [Email] (#1463) [Profile/Gallery] (more from Gary Stottler) on Fri, 11 May 2012 06:53:09 In Reply to: Re: 80 Turbo....hunting/erratic...at idle..., Slyde, Thu, 10 May 2012 16:38:21 Members do not see ads below this line. - Help Keep This Site Online - Signup |
Slyde,
It's a little difficult to say why it idles until you touch the throttle - obviously a lot of things start to change then when you change the airflow by moving the throttle blade. It is possible that the metering rod in the fuel distributor is sticking, or more likely that the airflow plate is dirty, sticking, or binding somehow.
Once you've done all the air leak checks we talked about, you can take the fuel distributor/airflow sensor off (I would not separate the two pieces just yet)and clean the whole thing carefully with shop solvent. Maker sure that the airflow plate doesn't have any gunk on it (can be caused by any kind of air leak in the air filter housing or PCV) and that it moves easily without sticking or binding and doesn't touch the edge of the metal venturi. It is possible but not common for the metering rod in the fuel distributor to get gum/varnish on it and not move up and down smoothly with the airflow plate. You can remove it (very carefully, don't drop it or do anything to scratch/ding it) and inspect it. If it seems dirty you can lightly polish it with carb cleaner and 2000 grit sandpaper (1600 grit is probably OK, but I wouldn't go any coarser than that). Otherwise, there's not much that can go wrong with the fuel distributor other than an internal leak which does not sound like the problem.
I think that the fuel distributor is available if needed. I hesitate to try a later one. It might work, but you might end up chasing your tail with driveability problems, and I don't recall all the permutations of how they hooked up the modulating valve. Just go by the Bosch part number on the side of the black fuel distributor body. Last I knew there were still a couple in the warehouse and you can probably get a used one from Chip or Bill Jacobsen.
Talk to you next weekend!
Gary
posted by 198.208.15...
_______________________________________ Gary Stottler
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