1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

High idle for no apparent reason??

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Old 08-06-10, 01:06 PM
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SoxSider
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High idle for no apparent reason??

Another issue with my RX7. This time it's idling much higher than it should. I went to start my car today, and used the choke of course since I hadn't ran the car since yesterday. Well now, with the choke pushed in, it idles at 1500RPM. Before today it idled at around 800-1000.

Playing around with it, I shut the car off and started it again, to see if it would go back to normal. Well, when I restarted it, it idled at like 900 like it should. But, when I revved it up to like 2000, the idle wouldn't go back down to under 1000. It went back to 1500 and stayed there.

I'm confused as to why this randomly happened and I don't like the car idling at 1500. Does anyone know how I can resolve this problem?
Old 08-06-10, 02:59 PM
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Sounds like you have a sticky linkage.

And it should idle at 750.
Old 08-06-10, 03:02 PM
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+1

check for sticking in the linkage and/or the cable.
Old 08-06-10, 05:48 PM
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SoxSider
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Are you guys talking about the linkage on the choke?? If so, how can I lube that up?
Old 08-06-10, 05:54 PM
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Can spray the linkage on carb with carb cleaner working the linkage back and forth,

if that does not remedy it if I dare suggest check for a vacuum leak

Last edited by 13x; 08-06-10 at 05:57 PM. Reason: if less complete of a thought lol
Old 08-06-10, 09:05 PM
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speaking for myself only ... i was talking about the accelerator cable and the actual throttle linkage (the rod and primary and secondary springs that actuate the butterflies). clean and lube them and make sure there is nothing impeding their motion.
Old 08-07-10, 12:00 AM
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Sounds like a sticky throttle. There are quite a few things on the carb that can rub against each other and prevent the throttles closing consistently. Have a look around where the accelerator cable joins the carby, open and close the throttle by hand, etc... it takes a bit of inspection to find if this is your problem.
Old 08-07-10, 03:51 AM
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Try this?

I thought I was having idling troubles similar to yours. I looked at my timing and was ready to adjust my mixture until, just for giggles, I put my foot under the gas pedal and pulled up. Instant cure.

I've sprayed my linkage but I still have the problem. I may need to spray it again, but as of now I still have the problem. I haven't had a chance to determine if the spring is weak or if the dashpot needs adjustment. I've read a thread here somewhere here where someone added a stronger spring to help everything to return to normal.

These cars are old.

Cheers.
Old 08-07-10, 04:54 AM
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Originally Posted by lazlong
I thought I was having idling troubles similar to yours. I looked at my timing and was ready to adjust my mixture until, just for giggles, I put my foot under the gas pedal and pulled up. Instant cure.

I've sprayed my linkage but I still have the problem. I may need to spray it again, but as of now I still have the problem. I haven't had a chance to determine if the spring is weak or if the dashpot needs adjustment. I've read a thread here somewhere here where someone added a stronger spring to help everything to return to normal.

These cars are old.

Cheers.
Dude if pulling the pedal closes the throttle a bit more, your accelerator cable could be too tight on the carby bracket. It needs a bit of play there, try backing it off a bit. There are two nuts that hold it on the bracket on top of the carby.
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