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Old 09-18-2012, 09:23 PM   #4
SubDad
2nd Gear Member
 
Join Date: Apr 2012
Location: Ottawa
Posts: 172
I like the leaking injector theory.

This car was parked for 8 months until I bought it and another 2 months before I found an ECU that worked. (From a junkyard in Germany - ordered on Sunday delivered on Friday via Canada Post: Wow. ).
I'm on the second tank of gas, into the first (old) one addded injector cleaner.

It's an L-Jetronic, the analog pre cursor to Motronic. It can't be chipped, there's no chip. It could have been opened, but it's held closed by rolled rivets and didn't seem to me have been opened when I installed it, but I didn't check that closely.
I disconnected the MAF (which is actually a VAF, Vane Air Flow sensor, apparently, http://www.diycardoctor.com/how_the_...nsor_works.htm) and because the system has no throttle position sensor it won't even start with no air sensor. It has two throttle switches, one each for WOT and closed throttle.
There's a vacuum pot that holds the throttle off closed except when the manifold vacuum is reduced rapidly. It probably would have started on the signal from the throttle closed switch if I'd held back the pot rod.

While doing that it occured to me (Duh!) that even if the air filter was completely clogged the volume or even mass of air would be reduced, and since the job of the M/VAF is to sense the actual air the air filter can't affect anything but max output.

Yes, I like the leaking injector theory. I suppose a set of really dirty injectors could do the same thing.
I need to think about the inline resistor idea. From the website above: "Inversely proportional systems (L-Jetronic) output a high voltage at idle with the voltage decreasing as air flow increases."

Hmmm.
Sorry for thinking out loud.
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