1986 Tercel 4x4 (3AC Engine)

Hello Everyone:

My Toyota started to lose horsepower and pickup over about a week
period. It caught me in a surprise situation, so I was unable to get a
diagnosis as the first symptom appeared.

It all started by the car not pulling uphill well. Instead of going
uphill and holding 60 mph it was reduced to 45-50 mph. From there it
was a continuous degradation of performance.

The only way I was able to get any RPM's out of it was to choke the
carburetor by cupping my hands over it and gradually letting air in.
After I was able to get RPM's, I had to hold them with the throttle,
when the RPM's got bellow 2 thousand the engine seemed to delay when
the pedal was applied quickly. When the gasoline pedal was floored the
engine non-responsive and wanted to stall.

The Tercel, at idle, was very rough, sometimes it was possible to get
the engine to rev when applying the gasoline pedal very slowly and
smoothly. When driving the Tercel in this degraded state it would pull
out of a complete stop on about half power, like I said, once over 2
thousand RPM's the engine appeared to have some pickup.

When removing the original carburetor I noticed that gasoline was
puddling in the intake manifold, I cleaned the gasoline out and applied
new mounting gaskets. Same symptoms.

I have tried a second carburetor from the junkyard and the same
symptoms appear. With both carburetors the intake manifold was flooded.

Here is what I changed in hopes of fixing the ailment:

1) The majority of the vacuum hoses/tested all hoses
2) Carburetor/Mounting Gaskets

As of now, the Tercel does not want to start on its own.

An unofficial local mechanic checked the timing belt, which was
apparently in good condition.

A second unofficial mechanic checked the spark of the spark plugs and
said the spark was weak and suggested the coil in the distributor and
to disassemble one of the carburetors and check the float level. I have
not entered into either venture.

I would sure appreciate and helpful hints/suggestion/insight into this
problem. I am unable to drive the Tercel to a shop and would prefer not
to have it towed because of monetary reasons.

Thank You.

Hello Everyone,

I have some new progress to report with my Tercel, It is not running
yet, but I have been narrowing down the possible culprits.

The Carb sight glass is fine, the gasoline in the sight is about
halfway up and down.

The car has new spark plugs and the spark also appears to be fine, all
four plugs are firing, and the wires are known to be good.

The Tercel has now had three carbs on it, the most recent which is
number three is known to be good, there is still pooling in the intake
manifold.

I have done a compression check and the results are as follows:

Cylinder 1:
120 PSI normal and 150 PSI With a teaspoon of oil

Cylinder 2:
110 PSI normal and 150 with oil added

Cylinder 3: 120 PSI normal and 150 PSI with oil added

Cylinder 4: 100 PSI normal and 150 PSI with oil added

I have heard and read that if two consecutive cylinders have at least
20 PSI or more difference there may be a head gasket leak. Can this be
the culprit or just a culprit?

Thanks again for anyone who is willing to help me solve this problem.

"Ken LaCroix" <kp.lacroix@gmail.com> wrote in message
news:1130125900.875627.198760@g47g2000cwa.googlegroups.com...[color=blue]
> Hello Everyone,
>
> I have some new progress to report with my Tercel, It is not running
> yet, but I have been narrowing down the possible culprits.
>
> The Carb sight glass is fine, the gasoline in the sight is about
> halfway up and down.
>
> The car has new spark plugs and the spark also appears to be fine, all
> four plugs are firing, and the wires are known to be good.
>
> The Tercel has now had three carbs on it, the most recent which is
> number three is known to be good, there is still pooling in the intake
> manifold.[/color]

Start looking at something external to the carburetor, like the fuel line
leading to the carb. The flared fitting may not be sealing and fuel is
leaking and air is getting in. Leaking fuel could account for the pooling
fuel in the intake manifold. When the engine is running, if you look down
the venturi, is the fuel atomizing or is it dribbling?
[color=blue]
> I have done a compression check and the results are as follows:
>
> Cylinder 1:
> 120 PSI normal and 150 PSI With a teaspoon of oil
>
> Cylinder 2:
> 110 PSI normal and 150 with oil added
>
> Cylinder 3: 120 PSI normal and 150 PSI with oil added
>
> Cylinder 4: 100 PSI normal and 150 PSI with oil added
>
> I have heard and read that if two consecutive cylinders have at least
> 20 PSI or more difference there may be a head gasket leak. Can this be
> the culprit or just a culprit?
>
> Thanks again for anyone who is willing to help me solve this problem.
>[/color]
A head gasket leak would not cause fuel to pool in the intake manifold.
Cylinder 4's compression is low but probably not worth trying to remedy on a
car that is close to 20 years old.
--
Ray O
correct the return address punctuation to reply

On Sun, 23 Oct 2005 20:50:34 -0700, Ken LaCroix wrote:
[color=blue]
> Hello Everyone:
>
> My Toyota started to lose horsepower and pickup over about a week
> period. It caught me in a surprise situation, so I was unable to get a
> diagnosis as the first symptom appeared.[/color]


Son of a gun, I just scrapped one of these a couple months ago! I would
have GIVEN it to you; it had a great engine...


[color=blue]
>
> It all started by the car not pulling uphill well. Instead of going
> uphill and holding 60 mph it was reduced to 45-50 mph. From there it
> was a continuous degradation of performance.
>
> The only way I was able to get any RPM's out of it was to choke the
> carburetor by cupping my hands over it and gradually letting air in.
> After I was able to get RPM's, I had to hold them with the throttle,
> when the RPM's got bellow 2 thousand the engine seemed to delay when
> the pedal was applied quickly. When the gasoline pedal was floored the
> engine non-responsive and wanted to stall.
>
> The Tercel, at idle, was very rough, sometimes it was possible to get
> the engine to rev when applying the gasoline pedal very slowly and
> smoothly. When driving the Tercel in this degraded state it would pull
> out of a complete stop on about half power, like I said, once over 2
> thousand RPM's the engine appeared to have some pickup.
>
> When removing the original carburetor I noticed that gasoline was
> puddling in the intake manifold, I cleaned the gasoline out and applied
> new mounting gaskets. Same symptoms.
>
> I have tried a second carburetor from the junkyard and the same
> symptoms appear. With both carburetors the intake manifold was flooded.
>
> Here is what I changed in hopes of fixing the ailment:
>
> 1) The majority of the vacuum hoses/tested all hoses
> 2) Carburetor/Mounting Gaskets
>
> As of now, the Tercel does not want to start on its own.
>
> An unofficial local mechanic checked the timing belt, which was
> apparently in good condition.
>
> A second unofficial mechanic checked the spark of the spark plugs and
> said the spark was weak and suggested the coil in the distributor and
> to disassemble one of the carburetors and check the float level. I have
> not entered into either venture.
>
> I would sure appreciate and helpful hints/suggestion/insight into this
> problem. I am unable to drive the Tercel to a shop and would prefer not
> to have it towed because of monetary reasons.
>
> Thank You.[/color]

I have taken a few pictures of the Carb assembly and have recorded the
sound of the engine, if it helps. Here it is:

[url]http://inconcepts.us/toyota/[/url]

"Ken LaCroix" <kp.lacroix@gmail.com> wrote in message
news:1130185028.913343.153450@g44g2000cwa.googlegroups.com...[color=blue]
>I have taken a few pictures of the Carb assembly and have recorded the
> sound of the engine, if it helps. Here it is:
>
> [url]http://inconcepts.us/toyota/[/url]
>[/color]

I don't remember... Does this car have a mechanical or an electric fuel
pump?

What is the brown stuff all over the stuff around the carb? Did the engine
overheat?

Is the mounting plate on the intake still a flat plane?
--
Ray O
correct the return address punctuation to reply

A mechanical fuel pump, and when I checked it awhile ago it was fine.

This carb came from Minnesota, and they use salt on their roads, so
thats rust.

No the engine never over heated.

Yes, the mounting plate is flat.

Thanks Ray for the help you have given me so far, its appreciated,

"Ken LaCroix" <kp.lacroix@gmail.com> wrote in message
news:1130188106.350846.67450@g49g2000cwa.googlegroups.com...[color=blue]
>A mechanical fuel pump, and when I checked it awhile ago it was fine.[/color]

This was a really long shot, but since the carb and intake were on the side
of the block and if the mechanical fuel pump's diaphram or case was leaking
somehow, I thought it might somehow get into the intake.
[color=blue]
>
> This carb came from Minnesota, and they use salt on their roads, so
> thats rust.
>
> No the engine never over heated.[/color]

I wasn't sure if the brown was rust or residue from an overheated engine or
radiator that sprayed all over the place.[color=blue]
>
> Yes, the mounting plate is flat.[/color]

Again, this was a really long shot, but if the engine overheated, then the
mounting plate for the intake might have warped, allowing even a good
mounting gasket to leak. If it was sucking air, that would account for the
need to "choke" the carb to make it run.

Just for grins, it might be worthwhile borrowing or buying a vacuum gauge to
make sure you don't have a vacuum leak from some off-the wall place, like a
vacuum switching valve. You should have in the vicinity of 18 in.hg. at
idle.[color=blue]
>
> Thanks Ray for the help you have given me so far, its appreciated,[/color]

Don't thank me yet - I haven't fixed your car yet!
--
Ray O
correct the return address punctuation to reply

Man, this is turning into quite the project.......

I dont think I know anyone with a vacuum gauge, and they are pretty
expensive I have been told.

But anyway, It looks like the timing is up to specs, it has a
known-to-be-good carb on it, new mounting gaskets, the cyl compression
also looks to be in specs, I just cant imagine what else is could be.

Could it be the distributor? It would be odd that the distrbutor is
sending electricity to all the plugs, but have some internal defect, is
that possible? What part(s) could be defecting? If they where.

If anybody has any other suggestions, I am all ears.

Thanks

-Ken

On 25 Oct 2005 13:13:08 -0700, "Ken LaCroix" <kp.lacroix@gmail.com>
wrote:
[color=blue]
>Man, this is turning into quite the project.......
>
>I dont think I know anyone with a vacuum gauge, and they are pretty
>expensive I have been told.
>
>But anyway, It looks like the timing is up to specs, it has a
>known-to-be-good carb on it, new mounting gaskets, the cyl compression
>also looks to be in specs, I just cant imagine what else is could be.
>
>Could it be the distributor? It would be odd that the distrbutor is
>sending electricity to all the plugs, but have some internal defect, is
>that possible? What part(s) could be defecting? If they where.
>
>If anybody has any other suggestions, I am all ears.
>
>Thanks
>
>-Ken[/color]

I am NOT an expert....but one thing I noticed...

Your plug wires are not OEM.

Could that be your problem?

--

Scott in Florida

Still Voting Democratic?

You are Stuck On Stupid!

On Tue, 25 Oct 2005 13:13:08 -0700, Ken LaCroix wrote:
[color=blue]
> Man, this is turning into quite the project.......
>
> I dont think I know anyone with a vacuum gauge, and they are pretty
> expensive I have been told.
>
> But anyway, It looks like the timing is up to specs, it has a
> known-to-be-good carb on it, new mounting gaskets, the cyl compression
> also looks to be in specs, I just cant imagine what else is could be.
>
> Could it be the distributor? It would be odd that the distrbutor is
> sending electricity to all the plugs, but have some internal defect, is
> that possible? What part(s) could be defecting? If they where.
>
> If anybody has any other suggestions, I am all ears.
>
> Thanks
>
> -Ken[/color]

Does it start and run OK? After I did a tune up on mine, it ran like shit!
(I used aftermarket wires, BTW)

What it was, was a short, large tube under the air cleaner that came off
when I replaced the air cleaner. After I replaced the hose we were up and
running just fine again...

"Ken LaCroix" <kp.lacroix@gmail.com> wrote in message
news:1130271188.809065.218850@g14g2000cwa.googlegroups.com...[color=blue]
> Man, this is turning into quite the project.......
>
> I dont think I know anyone with a vacuum gauge, and they are pretty
> expensive I have been told.[/color]

You should be able to get a Mighty-Vac for under $40. Some auto parts
stores rent tools, you might want to check into rental.
[color=blue]
>
> But anyway, It looks like the timing is up to specs, it has a
> known-to-be-good carb on it, new mounting gaskets, the cyl compression
> also looks to be in specs, I just cant imagine what else is could be.
>
> Could it be the distributor? It would be odd that the distrbutor is
> sending electricity to all the plugs, but have some internal defect, is
> that possible? What part(s) could be defecting? If they where.
>
> If anybody has any other suggestions, I am all ears.
>
> Thanks
>
> -Ken
>[/color]
Basically, 2 things go wrong with distributors: They don't send spark to
the plugs or the O-ring leaks and you get oil in the distributor, which can
prevent them from sending spark to the plugs. I can't think of any way that
a bad distributor would cause raw gas to pool in the intake manifold.

By the way, Toyotas seem to run better when using genuine Toyota ignition
parts, including cap, rotor, wires, and plugs.
--
Ray O
correct the return address punctuation to reply

Everyone:

I have solved the problem!

It appears that the timing belt had slipped two notches.

The crankshaft pulley was aligned with the first triangle, not the
middle triangle. I fixed that and it started right up.

What is a mystery to me is how there was a gradual loss of power until
it completely quite running. I wonder if there was a carb problem that
caused the engine to run low on HP, and while attempted to drive the
car in low RPMs caused the timing belt to slip?

Should I change the timing belt? Being that it slipped two notches, can
it be stretched?

Thanks,

-Ken

On Wed, 26 Oct 2005 17:11:53 -0700, Ken LaCroix wrote:
[color=blue]
> Everyone:
>
> I have solved the problem!
>
> It appears that the timing belt had slipped two notches.
>
> The crankshaft pulley was aligned with the first triangle, not the
> middle triangle. I fixed that and it started right up.
>
> What is a mystery to me is how there was a gradual loss of power until
> it completely quite running. I wonder if there was a carb problem that
> caused the engine to run low on HP, and while attempted to drive the
> car in low RPMs caused the timing belt to slip?
>
> Should I change the timing belt? Being that it slipped two notches, can
> it be stretched?
>
> Thanks,
>
> -Ken[/color]


I would. THis is an interference engine! You're kinda lucky it's still
running.

Hey if ya wanna sell it...I miss my '83. I painted it BRIGHT YELLOW!!
since I drove it a lot at night in the winter.
[url]http://www.netwiz.net/~tcar/images/cpaintchips.jpg[/url]

Yellow Topaz, except I added a Pearl Coat top coat. Boy was it BRIGHT!!!

Nah, I don't have any plans to sell it at the moment, but I may at a
later date.

But, what the heck where you doing driving around at night in the snow?