High idle cold start --sorry

[82DMC12]

So after cleaning and testing everything and all the research i came across a picture of throttle spool spring and realized mine was either an old style or something rigged up from previous owner. I changed out the spool spring and cold started it today and it jumped up for a second but then dropped down as soon as i threw a rev. then it hunted for about 30 seconds but stayed under 1k rpm. Huge improvement from before! Maybe something to do with what Parzival mentioned earlier in thread? tensions on the springs? Its only been one cold start try but i am hopeful its fixed.
Last question for the week hopefully, I ordered the other return spring(pic) seems as though I have to tear a lot apart to get to that bolt. Any suggestions on easy way to replace it?

Thanks


Dave T.

In the first picture, you can increase the tension on the top spring for the throttle spool by holding the spring and lifting it out of the two channels it's currently in, and rotate the top of the spring clockwise so that it fits into the next pair of channels. Does that make sense?

In the second picture, you will need to remove the throttle body from the car in order to adequately service (grease) that spring. You'll have to remove the W-pipe, disconnect the two wires from the back of the idle speed microswitch, and disconnect the linkage from the lever that hits the idle speed microswitch. Remove the vacuum hose from the bottom of the throttle body. Then remove four allen cap screws to remove the throttle body with the black bellows attached. Now you can work on it on a bench.

Andy

[Rich]

Last question for the week hopefully, I ordered the other return spring(pic) seems as though I have to tear a lot apart to get to that bolt. Any suggestions on easy way to replace it?

Andy posted good answers for both of those springs.

The spring on the throttle butterfly shaft (much harder to replace than the spool spring) might not need attention. Yours doesn't look like a PO tried to grease it up and it looks pretty clean.

These springs don't "lose tension" over time so if it was installed correctly and is as clean as it looks then it's probably delivering the design torque to the shaft linkage already and there is little need for a new one. The coils seem to have space between them, not gunk, so very little friction there. To be extra sure you can blast its coils with aerosol brake cleaner right where it sits. Fully open the throttle linkage by hand to get at more of the coils for cleaning.

Final check: Does the throttle linkage arm with the "idle screw" on it now bottom out reliably against its stop every time your foot's off the gas? And the idle control circuit is engaged in that condition? Then there's no need for mo-better springs.

[Elvis]

Did you already test a known good idle ECU ?

[glockworks21]

thank you for all the help. a lot was cleaned up and tested. I think the bulk of the problem was that tension on that old style throttle spring. The high idle seems to be fixed! I will be posting my next issue in a moment.. )

Thanks!