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Hey guys

Trying to help a friend out here. 1990 Tercel (carbureted) tough to start when cold. Have to keep foot on gas for a few seconds because the car loads up terribly.....runs very rich and smells of gas bad. After that the car will run, but very rough for 2-3 minutes. Then, all of a sudden it clears up and runs fine. It's almost as if the choke pull off (if there is such a thing on these cars) is not working, then the choke heats up and opens. I'm not familiar with these Toyotas...anyone have any idea on what this could be? Again, only on cold start ups.....and we're carbureted.

Thanks!
 

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I have the same issue, I did a weber conversion and didn't put a fuel regulator on ,...... since then put one on and it is a little better. Is your car stock (carburator)? Prior to converting mine it would start but hard like yours, but wouldn't idle. the stock carburtors on Tercls 90 and earlier were a factory defect. I spent soem tiiem trying to fix mine but it wasn't possible and toyota repalcements were expensive and not garanteed. The weber conversion is the most popular fix and more likely to work,.... if it is the carburator.
 

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89 Tercel EZ
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332 Posts
There's a variety of things that activate at certain engine temperatures. It could be the choke as you suspect. I'd give it some carb cleaner directly into the intake to address that possibility - if it helps, it's probably just gunked up.

It could also be a BVSV (thermally activated vacuum switch - yellow things sticking out the side of the engine block with three vacuum ports) that is causing a vacuum leak when in it's cold position (due to a leak in the hose or widget connected to the cold side). The one that clicks on first activates the ECU to control the fuel air mixture when the engine is above 43*F. It leans out the mix by letting in more air as necessary to keep fuel/air mix ideal. Until the engine reaches 43*F, another vacuum widget controls the fuel/air mix. I discovered on my car that widget was bad and was responsible for the engine running too rich when not warmed up. Check the swap guide in my signature in the "STEP NINE" section to see the one I'm referring to. This link may also be helpful in understanding the stock vacuum system: http://repairnet.aircare.ca/documentation/newsletterpdfs/toyotatercel.pdf
 

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1992 paseo
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its been a while since i have worked on one of those cars, but pretty much any car that is carbureted has a choke pulloff, unless its a manual choke car like the old rx-7's. The way the choke sysytem is supposed to operate is by pressing down on the gas pedal, which the accelerator pump in the carb shoots in a stream of fuel, at the same time it allows the bimetallic choke spring to close the choke. Unpon cranking the engine, when it fires up, the engine vacuum is applied to the choke pullof valve to crack open the choke to let enough air in so the engine can breath and still enrichen the air/fuel mixture til the choke spring heat up and open the choke. The choke pulloff typically looks kinda like a flying saucer but has a vacuum line attached to one end and the other end has a linkage that connects to the choke flap. By pulling the vacuum line off of the choke pulloff and then reconnecting, watch the opposite side where the linkage connects to it. It should immediately retract to open the choke. It you grab the linkage it should be hard to pull it back out with the engine running.Sometimes the linkage can be out of adjustment, but usually it should open the choke valve approxiamately a 1/4 inch.
 
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