It starts but doesn't idle or stay running

[MarvinElliott]

Hi

I have a 1984 tercel sr5 wagon
I replaced the spark plugs and fuel filter it has a small gas leak very small it hasn't ran in a year it has a sort of new fuel pump but I don't know what is making it not run if you could help me that would be amazing

[dlb]

Have you checked for vacuum leaks, and gone over the various carb settings to make sure they're correct?

[MarvinElliott]

No I'm 14 and am getting in to fixing cars and this is the first time working on everything so if you could tell me what might be the problem that would be amazing

[NWMO]

Marvin,

Internal combustion engines require 3 things to start/run (assuming timing is adequate): compression, fuel, and spark. Assume compression is ok if running before and start by checking for spark and fuel. If you have spark, you should be able to squirt fuel in the top of the carb and at least get it to “fire” some.

Chris

[MarvinElliott]

I tried to start it and it will for like 2 seconds and then it dies out so I know it is getting gas and spark somehow but in thinking it might be clogged fuel lines or I need a new fuel pickup I know it has gas In the tank the two front tires are flat and it's on a very little decline so it might need a new fuel pump and it just use the gravity

[Mark]

Check and see that the choke breaker diaphragm is working. When you start the engine, the choke is closed. After about 1 or 2 seconds, that choke opener is supposed to open the choke just a bit. If it doesn't, there will not be enough air for the engine to run and the engine will probably stall like yours does after a couple of seconds. The photo below might have a bunch of components that are not in all versions of the Tercel, but they all should have the choke breaker (circled in red). Take off the air filter housing cover so you can see down into the carb. The choke will probably be closed. Get someone to start the car while you are looking down at the choke. It should open just a little bit about a second or two after it starts running.

choke breaker.jpg

If this test works fine, then the choke breaker is not the issue (it was on my Tercel. The rubber diaphragms in these components eventually get holes in them over the years and they don't work anymore).
So if the choke breaker works fine, then I'd try getting a spray can of carb cleaner (which is flammable). With the air filter cover still off, get someone to try starting it again and spray some carb cleaner into the carb. If it's stalling from not getting fuel, then spraying the carb cleaner acts like fuel and the engine should run while you are spraying it.

[MarvinElliott]

Thanks for that buddy
I just started it and it idled high and it was getting hot fast
Do you know what may cause that

[MarvinElliott]

And do you know if this part (the green one broke )could be the reason for it being hot

[Mark]

I think that's the thermo switch that sends a signal to the computer for emissions stuff. It shouldn't make your car overheat. You could probably unplug it and not really notice the difference. How long does it take to get hot? How high is it on the temperature gauge in the dash?

[MarvinElliott]

It's about half on the temp gauge after 15 minutes of idle
And it idles at 1800 rpm

[Mark]

That temperature seems about normal. Once it's warmed up, the needle should sit around the halfway mark. And 15 minutes at idle is a reasonable amount of time to warm up. I'd even expect it to warm up a bit faster than that.
That idle speed is really high. It should idle at 600-900 rpm depending on if it's an automatic or a standard. There is a fast idle mechanism on the carb that makes it idle high at first. Basically, when the engine is cold, you push the gas pedal down once before starting it. That sprays a bit of gas into the carb and sets that fast idle mechanism. The engine will then start and idle much faster than normal (I forget the exact speed, but 1800 rpm seems about right). Once the engine warms up a bit, you push the gas pedal down almost to the floor again. This releases the mechanism and drops the idle speed down to normal.
When your engine is warm and idling very high, try that method of pressing down the gas pedal then releasing it and see if the idle speed drops.

[MarvinElliott]

Ok thanks soooo much

[MarvinElliott]

So I started it today and it idled at 1000 rpm
But it bounces between 900 to 1100 sometimes
but on the carburator the air thing that moves when you floor it to let more air in is stuck open and makes it stall
And it's a five speed manual

[Mark]

That flap that opens and closes in the top of the carb is the choke. When the engine is warm, it's supposed to stay open. The throttle plates that open and close when you press the gas pedal are deeper in the carb. You might need a flashlight shining down into the carb to see them properly. They should never be stuck open when you are not pushing the gas pedal.

[MarvinElliott]

Ok it's on the top but when you press the pedal down all the way they open I might be able to get a picture of it