Throttle sticking after carb rebuild

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Notmikeb
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Re: Throttle sticking after carb rebuild

Post by Notmikeb »

I believe the vacuum leak was present before the rebuild as many of the symptoms were present before (rough idle, flat spot in acceleration, slight rpm surging at idle) but it has gotten very much worse since the rebuild. I guess when you clean a dirty vacuum leak it just becomes a bigger vacuum leak :D
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1985 Tercel 5dr Hatchback
2003 Chevy Suburban
2014 Ford Flex

"I don't get it! I've cut this thing FIVE times now and it's STILL too SHORT!"
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marlinh
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Re: Throttle sticking after carb rebuild

Post by marlinh »

So, where was the leak?
Notmikeb
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My tercel:: 85 Tercel 5dr FWD
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Re: Throttle sticking after carb rebuild

Post by Notmikeb »

Still haven't had a chance to diagnose yet. Had a three year old that refused to go to bed. Going out to check in a bit.
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1985 Tercel 5dr Hatchback
2003 Chevy Suburban
2014 Ford Flex

"I don't get it! I've cut this thing FIVE times now and it's STILL too SHORT!"
Notmikeb
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Posts: 235
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My tercel:: 85 Tercel 5dr FWD
Location: Laurel, MD

Re: Throttle sticking after carb rebuild

Post by Notmikeb »

At a loss. Can't find any vacuum leaks. Checked all the hoses and their routing. Tightened down the carb (was already fairly tight). Tomorrow I'll start going through each device one by one and start testing as per the FSM.

This is what my vacuum is doing at idle and at partial throttle

http://youtu.be/v9XC2Rh1MZM

Does this seem like a vacuum leak? Am I barking up the wrong tree here? Do I have another issue?
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1985 Tercel 5dr Hatchback
2003 Chevy Suburban
2014 Ford Flex

"I don't get it! I've cut this thing FIVE times now and it's STILL too SHORT!"
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irowiki
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Re: Throttle sticking after carb rebuild

Post by irowiki »

Almost sounds like your throttle positioner is off or has a leak.
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Notmikeb
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My tercel:: 85 Tercel 5dr FWD
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Re: Throttle sticking after carb rebuild

Post by Notmikeb »

It does the same thing whether the throttle positioner is connected or not.
-------------
1985 Tercel 5dr Hatchback
2003 Chevy Suburban
2014 Ford Flex

"I don't get it! I've cut this thing FIVE times now and it's STILL too SHORT!"
Notmikeb
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My tercel:: 85 Tercel 5dr FWD
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Re: Throttle sticking after carb rebuild

Post by Notmikeb »

As an interesting note, I found a small ball bearing in one of the lines coming from the TVSV. And no, it didn't get sucked out of the carburetor as both fittings on either end are too small to have one this big pass through (not sure how that would happen even if they were). PO was trying to fix something but I can't imagine what.
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1985 Tercel 5dr Hatchback
2003 Chevy Suburban
2014 Ford Flex

"I don't get it! I've cut this thing FIVE times now and it's STILL too SHORT!"
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irowiki
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Re: Throttle sticking after carb rebuild

Post by irowiki »

Which line exactly? He was trying to block it, but why?
Former Tercel Enthusiast (not a practical family car anymore but they still have a place in my heart)

Site administrator, if something is broken, PM me!

87 Corolla FX16, 105k
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irowiki
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Re: Throttle sticking after carb rebuild

Post by irowiki »

Check the choke opener and both diaphragms of the choke breaker next.
Former Tercel Enthusiast (not a practical family car anymore but they still have a place in my heart)

Site administrator, if something is broken, PM me!

87 Corolla FX16, 105k
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05 Avalon, 199k
Notmikeb
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Re: Throttle sticking after carb rebuild

Post by Notmikeb »

It was the line from the k port to the "gas filter"

The car runs normally when cold and it first starts up and has a normal steady idle. The cycling rpms don't start until it's been running for a minute or two. This is leading me to believe the leak is somewhere in one of the systems that opens up when the engine warms up. I've got some new vacuum lines coming in today from Amazon so I'll start replacing them one by one and testing each system as I go.
-------------
1985 Tercel 5dr Hatchback
2003 Chevy Suburban
2014 Ford Flex

"I don't get it! I've cut this thing FIVE times now and it's STILL too SHORT!"
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marlinh
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Re: Throttle sticking after carb rebuild

Post by marlinh »

In the past I used to see ball bearings stuffed in the end of vacuum lines. I think people were trying to block off hoses but make it look like everything was still connected.
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irowiki
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Re: Throttle sticking after carb rebuild

Post by irowiki »

Blocking off the line going from Port k to the gas filter would cause all kinds of poor running
Former Tercel Enthusiast (not a practical family car anymore but they still have a place in my heart)

Site administrator, if something is broken, PM me!

87 Corolla FX16, 105k
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Gottolovem
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Re: Throttle sticking after carb rebuild

Post by Gottolovem »

Years ago I had a car that refused to pass smog 1970 caddy
After talking to a friend of mine who is a mechanic he promptley walked out to the car in question poped the hood picked up a stick off the ground and shoved it into a specific vac line.
He said go see if it will pass now then replace the vac line "it passed"
Notmikeb
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My tercel:: 85 Tercel 5dr FWD
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Re: Throttle sticking after carb rebuild

Post by Notmikeb »

It seemed to make no difference once reconnected with a new hose. That makes me wonder if something in that series isn't operating correctly hence the original "repair".
-------------
1985 Tercel 5dr Hatchback
2003 Chevy Suburban
2014 Ford Flex

"I don't get it! I've cut this thing FIVE times now and it's STILL too SHORT!"
xirdneh
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Re: Throttle sticking after carb rebuild

Post by xirdneh »

is the primary solenoid working properly?
Love those Tercell 4x4 wagons but they sure suffer from road noise.
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