Running rich

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irowiki
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Running rich

Post by irowiki »

I think the wagon is running way too rich so I'm looking for some tips.

The choke properly opens when she is warmed up.

I suspect it may be an elevation thing, jetted for sea level, but running at 5000+ feet all the time, with frequent trips over the mountains? No HAC yet, California emissions.

When ever I start her up when cold, she drips gas out of the exhaust pipe and runs quite rough. Strong gas smells and clouds of gas vapor (?).

In the past few weeks she keeps carbon fouling spark plugs, including this brand new set I just installed:

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Do I need to rejet her? Do carb rebuild kits come with jets? Will installing a working HAC make a huge difference?
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87 Corolla FX16, 105k
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dlb
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Re: Running rich

Post by dlb »

i have zero experience with the HAC but according to the fsm, because air/fuel mixtures become richer as altitude increases, the HAC leans out the fuel mixture and advances the timing when 4000 ft above sea level, so i think it would make quite a difference for you. i would try that first. i don't believe any carb rebuild kits have jets. it's not a part that is supposed to wear out.
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marlinh
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Re: Running rich

Post by marlinh »

Wow, that is some rich running. Have you checked if the idle mixture screw is out of wack? If the tamper proof cover is missing, maybe someone has adjusted it out of specification.
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Petros
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Re: Running rich

Post by Petros »

you may have a failed AAP, pull the vac line after you run it. If it is full of fuel, cap it off. that should solve the run rich condition.

It should be easy to install a HAC on any model Tercel as long as you have the three vac ports on the distributor vac advance.
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dlb
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Re: Running rich

Post by dlb »

Petros wrote:It should be easy to install a HAC on any model Tercel as long as you have the three vac ports on the distributor vac advance.
i think that even if the vac advance unit only has two ports, he should be able to install a 'T' into the line for the upper diaphragm and then one of these...

http://ca-en.hagen.com/Aquatic/Aeration ... ries/A1172

...into the HAC line and achieve the same effect. both ports on the upper diaphragm operate the same diaphragm. the only difference is the port that goes to the HAC has a smaller hole, which is what the fish tank valve would be for.
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Gottolovem
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Re: Running rich

Post by Gottolovem »

Was it this rich before you swapped distributor!
Maybe timing ?
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irowiki
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Re: Running rich

Post by irowiki »

Yeah, it nuked another set of plugs right before Christmas.

Notably, i think both times the plugs fouled were after a lot of shopping stops in the cold!
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
94 Jamboree RV (Ford E-350), 90k
95 Camry Wagon, 197k
05 Avalon, 199k
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