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> Rpm doesn't drop to idle very fast
Ian Stott
post Oct 6 2011, 05:09 PM
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As the title says (the idle is around 950/1000) but it doesn't drop down to that very fast, it is almost like driving a vehicle with a sticky throttle. I have just installed a new (rebuilt by Jeff Bowlsby) relay board and cleaned up my grounds and cleaned the engine compartment. Any ideas what is going on?

Ian Stott
Moncton
Canada
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luskesq
post Oct 6 2011, 05:16 PM
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Knowing what year, what engine and whether it is FI or carb'd would be helpful.

Keith
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Ian Stott
post Oct 6 2011, 06:28 PM
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Ooops, 73 2.0 all original D Jet.

Ian Stott
Moncton
Canada
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rnellums
post Oct 6 2011, 07:56 PM
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I had the same issue with mine when I rescued it from storage. 3-4 secnods after I let Off the throttle at 3k before it would drop. I replaced all the vacuum lines for starters, but the real issue was my AAR was stuck. I put PB in it and it don't seem the help much. I ended up pulling the top cap off and running a few hot/cold cycles wIth a blow torch and now all is well.
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Prospectfarms
post Oct 7 2011, 12:17 AM
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QUOTE(Ian Stott @ Oct 6 2011, 07:09 PM) *

As the title says (the idle is around 950/1000) but it doesn't drop down to that very fast, it is almost like driving a vehicle with a sticky throttle. I have just installed a new (rebuilt by Jeff Bowlsby) relay board and cleaned up my grounds and cleaned the engine compartment. Any ideas what is going on?

Ian Stott
Moncton
Canada



Could your throttle be sticking? Mine did, causing the idle to hang until I bumped the accelerator peddle. I cleaned it with carburetor cleaner.

Its been said that a failing deceleration valve can produce a vacuum leak. You might check out Anders

Since the TPS asserts a separate "idle circuit" when the throttle closes, I can't reason why the idle would ever "hang," unless the TPS is maladjusted or there is a physical problem with the throttle? That's a question not a statement of fact.
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Dave_Darling
post Oct 7 2011, 12:27 AM
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Some things that come to mind as possible causes:

Decel Valve sticking, hooked up wrong, or mis-adjusted.
Vacuum leak.
Advance in the distributor is sticking.
Vacuum advance/retard hooked up incorrectly.

--DD
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r_towle
post Oct 7 2011, 08:12 AM
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QUOTE(Dave_Darling @ Oct 7 2011, 02:27 AM) *

Some things that come to mind as possible causes:

Advance in the distributor is sticking.


--DD

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BK911
post Oct 7 2011, 09:13 AM
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I have this problem in a 356. If I keep the car in gear until the engine is at 1k rpms before I pop out of gear, perfect idle. If not, the idle slowly drops.

Do you guys think this indicates sticking advance plates or weak springs?

Not to hijak, but if so, you may want to do this "test" to narrow down to weak dizzy springs or gummed up advance plates.
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r_towle
post Oct 7 2011, 10:53 AM
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The problem occurs when the old grease (40 year old grease at least) gets hot and becomes very sticky.

Its a 20 minute fix.
Remove the advance plates, take out the little ball bearing and clean everything with your favorite cleaner.
add new wheel bearing grease.
Put it back in and set the dwell and timing.

Not super hard to do...and it very cheap to do.

I would not even waste the time testing...just do it if you have never done it...its part of the long term maintenance.

If you really want to test it...try flicking the rotor back and forth to simulate advance, but do it while the distributor is really hot....right after a long drive on the highway..
It should SNAP back to no advance...if not, its dirty.

Rich
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Ian Stott
post Oct 10 2011, 11:31 AM
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Well! Feeling pretty dumb on this one, new floor mats were creeping and putting pressure on the throttle, using my heel I pull the mat back and all is well. Just got back from Owl's Head in Maine, car ran great and what an absolutely fabulous place to visit, I give it an excellant rating and James Smith made sure we had some good roads to travel on! My buddy Steven got a trophy for his beautiful Ghia and we had really nice weather the whole time, super weekend.

Ian Stott
Moncton
Canada
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Chris Pincetich
post Oct 10 2011, 01:37 PM
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OMG (IMG:style_emoticons/default/beerchug.gif)
Wasn't that the problem that cost Toyota millions $$$??
At least you didn't wildly accelerate and cause an accident.
(IMG:style_emoticons/default/biggrin.gif)
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