More D-Jet, High Idle Lean Mixture Options

[ggress]

Just getting a '74 2.0 running that I purchased few years back. Replaced all fuel lines, vacuum lines, and FI Harness. It runs better than I expected but not good enough.

It idles too fast (1300 / 1400 RPM) considering throttle valve bypass screw is all the way in. Also, it runs lean (using WB A/F meter). I have set the mixture adjustment on the ECU full CW to get mixture around 13.7:1. I think I have covered all the common vacuum leak issues described in other threads. Any suggestions appreciated. I have two specific questions below.


1) Is my ECU P/N correct? The base P/N is correct but not sure what the 090 suffix means.

2) With the throttle valve bypass screw turned in full CW there is still vacuum getting past the screw. Does anybody know if that is normal ? I can put my finger over the port and feel vacuum. Maybe by design it is not meant to provide positive shut off but I don't have enough experience to say one way or the other.

Thx

[era vulgaris]

I'm in the same boat as you, except I've got a 1.7 Djet and my idle won't go below 1200.
I think my issue has to do with the PCV, however I don't think that'll be a problem for you as I believe yours is routed to the air cleaner.

Have you checked your intake runner boots, intake manifold gasket, throttle body gasket, oil filler base gasket, cold start valve gasket, injector seals, and that you have the correct injectors?

Another forum member pointed out to me that his high idle was caused by one of his injectors being installed accidentally slightly at an angle. Even though his injector seals were new, the injector not being dead on straight allowed air to get past the new seal. Could be something to check.