stalling when coming to a stop and wont idle...help!

[180racing]

Hello all,

I'm kinda new to the Tercel world and need some help with my 85 4WD wagon, A/T, 158K miles. I bought it about a month ago here in the northwest from a fella that couldn't get it to stop stalling under braking and I foolishly thought I could figure this thing out...so far not so much.

The problem: From cold it starts up great, immediately idles high and will kick down when warm or if you tap the throttle, it will idle in the driveway for hours. The car goes into gear just fine and will drive away with no hiccups but as soon as you start braking for a stop the car dies and after a few minutes of driving it completely refuses to idle and is hard to start.

The previous owner in an attempt to fix the stalling problem, replaced all of the vacuum lines, fuel pump and even a new carb. I in tern have double checked the routing of said lines, replaced the leaking carb base gasket, installed new cap, rotor, plugs and fuel filter. I have set the high speed idle, idle and timing. I have checked the float bowl level, cleaned and checked the vacuum advance, compression is between 150 and 165 on all cylinders.

I really love this car but I have no idea where to go from here...what am I missing please HELP!

[takza]

You could have a leak in the brake booster that would cause that. Unhook and block the vac line to the brake booster and CAREFULLY drive it to see if this fixes the problem? You probably won't have very good brakes though.

I have............ before........... shot some WD40 into the booster where there is a valve that can stick...sometimes helps.

[Petros]

welcome to the list!

sounds like a vacuum leak that is active when it is warm (or perhaps the choke is masking the problem when cold). You might take some carb cleaner and while it is idling spray it all over the components, gaskets and vac lines, including the vac advance on the distributor (if bad it will act like a vac leak). And the brake booster as noted above.

Also a faulty altitude compensator can cause that as well. check your fuel cut-off solenoid (simple test, see the FSM). You also might check the AAP diaphragm o the carb, if it is leaky it will run rich and could cause that behavior. Pull the vac line and see if it is full of fuel, if it is you can just disconnect it and block it off to see it that was the cause. Presuming the carb is not the cause (which assumes the replacement carb is also working properly), concentrate on all of the emission contorls and possible sourses of vac leaks beside the carb.

There are a number of system checks in the FSM for the carb and emissions controls, but the items above are the most common problem. So if none of them work out you can run through the full test procedure. IT is likely something simple, so do not panic and give up on it. You just have to systematically go through the process of elimination. Once you locate it fixing it, or by-passing it, will likely be the easy part.

Good luck.

[180racing]

Takza and Pertos thanks for the reply.

I forgot to mention that i unplugged the brake booster line, blocked it and took it for a spin...unfortunately that wasn't it. I also took apart the EGR and it was fairly clean. I will look into the Fuel cut off, AAP and altitude compensator sense I'm not even sure where or what those are.

I'll let you know how it goes.

[dlb]

the link to the factory service manual is found at the top of each page here. it has procedures for testing each of the emissions controls so give that a shot.

how is your air filter? doesn't sound like it's the problem but it's something else you might want to rule out.

you said once it has trouble idling, it's hard to start. once you do get it started, will it continue to drive ok up until you start braking again? maybe check for fuel and spark once it is hard to start.

[180racing]

I replaced the airfilter too...

Yes once it starts dieing and stops idling you have to hold the throttle in order for it to idle, this makes it hard to work on without an assistant to keep it running. Once it gets to this point, even holding the throttle, it no longer runs smoothly but instead surges and misfires. I have some guests in town for the weekend so I may not be able to work on it again until Sunday but keep the ideas coming I will get back to you with what I find!

Thanks!

[arbskynxnex]

You might check to see if your Throttle Positioning screw is set properly. Mine was not and would cause the car to stall when I stopped while driving. It is on the front of the carb and you can see the screw on page FU-10 on the factory manual. I found that when it was backed far enough off that it would let the throttle close enough to stall the car at any time you weren't holding the gas down. Just so you know ff you tighten the TP screw too much it will cause the engine too race as well since it holds the throttle open.

[180racing]

Update:

I didn't get as much time a s I needed this weekend to work on the tercel's stalling issue but I got a couple of things done. Checked the AAP diaphragm, looked good no leaks, rechecked throttle positioning screw, idle and timing none of these things helped. The engine valve train was kind of loud so i adjusted the valves, they were off and it seemed to help a bit but did not solve the problem. sprayed another can of carb clean around all of the vacuum lines trying to find a vac leak. No leak but I did manage to catch the distributor on fire and had a funny episode trying to put it out!

I still need to check the altitude compensator and other recommended things later this week.

[xirdneh]

how about the vac hose coming off the base of the carb on drivers side
was it connected to the air filter housing
if you have air filter housing off
did you plug that hose
if that was not it i would rebuild the carb (kits start at abt 26.00)
i keep several re-built carbs on hand for switching out
these tercel carbs cause problems for me on a regular basis
just a little crud or water in there and they start acting up

[takza]

You might check to see if your Throttle Positioning screw is set properly. Mine was not and would cause the car to stall when I stopped while driving. It is on the front of the carb and you can see the screw on page FU-10 on the factory manual. I found that when it was backed far enough off that it would let the throttle close enough to stall the car at any time you weren't holding the gas down. Just so you know ff you tighten the TP screw too much it will cause the engine too race as well since it holds the throttle open.

I had a stalling issue due to this....couldn't adjust per the FSM...had to leave the air cleaner off and adjust it by driving it....all you want is a slight slow down in the throttle drop?

[arbskynxnex]

Takza - A slow drop is what I gathered too, with the RPM staying in a certain range. I adjusted it with everything on and not according to the FSM directions. You can reach it with the air cleaner on and using a flat tip screwdriver that is at least a foot long. All I did was adjust it until it didn't stall, didn't race the engine and slowed down nice. It seemed like there was a sweet spot where it worked. My first test drive was fun after tightening the screw, it was racing enough after it warmed up that I had to ride the brake to keep it under 20mph.

[180racing]

all of the vacuum lines are routed correctly for my 85 California model even the ones at the base of the carburetor. I have heard somewhere that there might be a check ball in the carburetor that can become dislodged if the carburetor gets held upside down...which it has. Does anyone know if this is true and if so what does this check ball do and where is it located in the carburetor?

[xirdneh]

all of the vacuum lines are routed correctly for my 85 California model even the ones at the base of the carburetor. I have heard somewhere that there might be a check ball in the carburetor that can become dislodged if the carburetor gets held upside down...which it has. Does anyone know if this is true and if so what does this check ball do and where is it located in the carburetor?

there are four ball bearings (check valves)
1. one is under a brass screw
2. one has a small spring over it and a brass screw over that
3. one is at the bottom of the accelerator pump and a small "G" clip holds it in place
4. one (the large one) has a small spring over it and an aluminum piston like part over that and a small plastic disc over that the top of the carb presses down on that assy

the only one that could come loose by tipping carb over is the third one and then only if the "G" clip is missing or damaged
if that were the case it would probably pop out whether you tipped it over or not
i had a carb that i re-built but forgot to put the ball bearing in
the "G" clip was there
the car idled fine
when i stepped on the gas it was BLAHHHHHH and it would slowily build up speed

[180racing]

It doesn't look like my car has an altitude compensator, its a California car, does that sound right?

[john]

Hello,
Just checked under the hood of my '85 and did not see an HAC valve. My Chilton manuel says that Calif. cars have one, but I do not think they do. I bought my car from the dealer, here in Fresno.
john