My tercel won't go into high idle

[tercelingteen]

Hi, My Tercel wont go into high idle and I was wondering if anyone else had this problem, it has the stock carb on it and I haven't done any mods. so I was wondering if anyone had a solution to my problem.

[irowiki]

So, when it is cold, you press the pedal to the floor twice, start the car, and what happens?

[tercelingteen]

It will start and rough idle for a second and die, the only way it will stay running is if I sit in it and hold the pedal down.

[Petros]

Welcom e to the forum Tercellingteen,

Several things can cause that behavior. likely it could be a vacuum leak, or a bad choke/cold run system.

The procedure for finding a vac leak is over in the FAQ section (fairly easy, check for that first because nothing else can be verified if there is a vac leak, check all the vac lines and they are routed properly). Likely sorting out the vac lines, or vac leaks will solve the problem. BTW, likely cause is misrouted or disconneded vac lines, but the intake manifold or base of the carb could be loose and leaking, the temperature cyclines sometimes cause the bolts to back off.

Than verify if your choke is working, take the air cleaner assembly off, engine cold, plug the vacuum line that does to the underside of the air cleaner assembly. the choke should be open from the last time it was ran warm, when you stomp on the gas pedal to start the choke should close all the way. than start it, watching the choke, it should open when the engine is reved, and partially close when it is cold idling, slowing opening as it warms up. If it does not behave this way run through the service manual procedure tests for the choke and cold running systems.

Good luck.

[dlb]

here is the FAQ, see #6 and 7.

viewtopic.php?f=2&t=7442

how does the engine run once it's warmed up?

[tercelingteen]

Thank you! Once its warm it runs great.

[Mark]

I always seem to be answering posts with "when this happenned to me..."
When this happened to me it was the choke breaker. It had an internal vacuum leak in the diaphragm which wouldn't allow the choke breaker to work. Ther choke breaker opens the choke slightly on startup to allow enough air through to keep the engine running. It takes about a second to open when vacuum builds up. If it doesn't, the engine dies after idling for about a second or two.
I'd get someone to start the car with the air filter cover off and look at the choke. Even when it is closed, it should open by a few degrees when you start the car.

[tercelingteen]

Should I do that while the car is warm or cold?

[tercelingteen]

Could I put a manual choke in?

[dlb]

Could I put a manual choke in?

you don't need a manual choke. you're talking about making a bunch of work for yourself when you don't know if the choke is your problem yet. you need to sit down with the FSM, do a few tests to confirm what's wrong, and repair it. diagnose the problem before you try to fix anything.

Should I do that while the car is warm or cold?

in the FAQs is a link to download the factory service manual (FSM). download that and take a look at the emission system. find the section on the choke breaker and follow the steps to test it. it's easy. but don't forget to go through the other steps in the FAQ as well, looking for other vacuum leaks and whatnot.

[Mark]

Should I do that while the car is warm or cold?

When it's cold.

[Petros]

to repeat what DLB wrote to make sure you got it:

ALWAYS diagnose the problem BEFORE you try and fix it!!!

Or you will waste time and money and get very frustrated.

[tercelingteen]

IMG_20150421_155006.jpg

Okay, will do thank you guys! Also there is a sensor that has a broken wire and I'm not really sure what it is for.

[Petros]

that sensor is for the mixture control, might even be part of your problem. It is easy to fix, pull the connector off and pull that black rubber plug off the back side, you will see an ordinary bayonet type wire connector inside. YOU can either slip the old one out of the connector and attach a new one to the wire and reinsert it, or just add a connector and put it back on the sensor without the green connector housing (recommend repairing the connection within the connector housing).

Go through the service manual procedure for testing each of the systems, they are not difficult tests (things like "unplug X, listen for rpm increase").

The other sensor you can see in the picture, to the right of the vacuum valve on the front of the head, is the temp gauge sensor (next to the valve timing belt).

looks like you have the California emissions package, not the same as the rest of the country.

[irowiki]

That sensor also turns the manifold heater off, and whatever else the ECM does with the engine temp (like Peter said, mixture control too)

Definitely looks california!