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DuckRyder
Going to start trying to figure out the idle speed. It idles quite high when warm and properly when cold.

Is this the type of thing that a ECU/MPS/CHT mismatch can cause? idea.gif

I'm going to start running down pblanders page and checking everything, is there anything else that comes to mind?
DuckRyder
Allright, I may have answered my own question, but generated a few more.

It had a "037 = cu13x" ecu and a 043 MPS.

If I read the chart right that won't work.

So, I put a "052 = cu16x" ecu in and it seems much better.

Now, both of the mixture adjustment screws on both ECUs have clearly been F-ed with. one was maxed out one way, the other maxed out the other. Now, normally I wouldn't start screwing with that stuff, but since its already screwed with, I figured I'd take a shot at it.

In combination of the mixture and idle speed screw, I have it idling about 1000 luke warm. I'll warm it up and see if it maintains, and obviously a cold start will have to wait till morning or later, but:

1) Are there any "baseline" settings for:
a) Mixture potentiemeter
cool.gif Idle speed screw.

2) What am I missing?

The decel valve is completely removed and plugged if that helps.
Dave_Darling
The baseline settings are "whatever works". There should have been a mark in the little ring around the ECU knob, at least at one point. That was the factory setting where the knob had zero effect on the idle mixture. It's a decent place to start your adjustments from.

To me, sounds like you have a failed AAR. Pull the hose from the air cleaner to the AAR when the engine is idling cold. Does air get sucked in? That's good. Plug it back in, drive for 5-10 minutes. Now pull the hose again. Does air get sucked in? That's bad...

You can take them apart and repair them, but you should make certain that it's the AAR itself that is bad. Is it plugged in at the bottom, and does that get +12V when the fuel pump is running? Is the housing of the AAR grounded? If so, and the AAR doesn't close, then it's dead.

If you make that determination, I or someone else can post about repairing the thing.

--DD
DuckRyder
QUOTE
To me, sounds like you have a failed AAR. Pull the hose from the air cleaner to the AAR when the engine is idling cold. Does air get sucked in? That's good. Plug it back in, drive for 5-10 minutes. Now pull the hose again. Does air get sucked in? That's bad...


Right you are.
I'll test the electrics as soon as I get a chance. I have another one as well (I think).

It runs MUCH better with this 'puter.
DuckRyder
QUOTE
spray PB Blaster into it liberaly and soak it to free up the rotary valve inside. If the heater works it will get hot and the valve will turn. You try it with 12v to it.


woohoooo

Worked like a charm (assuming it opens again when cold)

Hell, I'll get the piece o shit running right before its over with!
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