Decel valve springs: replaceable?

[Morpheus]

GM everyone,

After putting my top end back together, I started it for the first time in 2 1/2 months last night.

After a few initial stumbles, the car roared to life and would not settle below 2000 RPM. I adjusted the linkage and actually held the throttle all the way closed and it had no effect. I seem to recall that when I had my throttle body apart for cleaning, the decel springs appeared to be like this picture:
Alex decel springs IMG_4178.jpg
(not my actual springs, but they look like this)

My question is this: Since new throttle bodies appear to be NLA, is there a way to replace these springs? If so, where would one acquire them? If not, is there some other solution? Can the springs be reconditioned?

I know high idle threads are plenty here, and believe me I searched for several hours for the answer to no avail.

[Bitsyncmaster]

If your springs look like that photo, they are NG. I don't think anyone has documented a replacement. You could measure some good springs and maybe use that data to find replacements. Or you could setup a test set to measure the opening of some replacement springs. My guess would be they open around 20 inchs/mg.

[Horsebox]

I can't really help you with your question but the guy in this blog replaced his entire throttle body for NOS, which brought his high idle down somewhat but not all the way...

http://delorean6575revisited.blogspo...-assembly.html

Have you gone for the low hanging fruit first? Such as microswitch connections, does the switch work electrically, does the screw actually trip the microswitch when the throttle is closed, does the idle motor get +12V, have any of the three pins in the connector on the idle motor backed out?

Sorry if that's not what you're looking for!

[Morpheus]

I was able to actually improve the idle quite a bit by adjusting the linkage and such. I'm bleeding the coolant system now, so after it cools off i'll check it again.

Unless someone knows of another source for throttle bodies, i guess i'm stuck. Best part, while tightening the 3 brass screws, I broke the head of one off. It's down tight, so I'm hoping it will hold.

[Bitsyncmaster]

I had bad deceleration springs and what would happen is with the curb idle all the way off, it would run about 1,000 RPM with a hot engine. It would hold 775 RPM until it warmed up. But with that curb idle all the way off the idle would undershoot to about 500 RPM when you took your foot off the throttle.

[Morpheus]

THat's exactly what mine does right now.

Start it up, it runs about 775 or so (haven't hooked up my dwell meter to verify, but it sounds normal and it's below 1000), then when it's hot it won't stay below 1000 - 1200.

[Delorean Industries]

I can hook you up with a good throttle butterfly and replacement brass screw. We have a surplus of good refurbished ones.

[Morpheus]

I'm very interested, Josh! What's the damage going to be?


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[DMCVegas]

THat's exactly what mine does right now.

Start it up, it runs about 775 or so (haven't hooked up my dwell meter to verify, but it sounds normal and it's below 1000), then when it's hot it won't stay below 1000 - 1200.

Lengthen the striker screw for the Idle Speed Microswitch, and then bend the bracket UP to engage quicker. You'll watch for RPMs drop at a slower rate.

[Morpheus]

Robert, how will that fix the springs on the butterflies?