'88 3SFE engine: no vacuum ANYWHERE!

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Old 11 Aug 2006, 02:17 pm   #1 (permalink)
geronimo
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Default '88 3SFE engine: no vacuum ANYWHERE!

Its an '88 Camry with 4 cyl. 3SFE engine. I have been trying to figure
out what is causing an extreme loss of power when the car is driven
just a short ways. Idling, sitting still, it will run just fine.
After driving a short ways the engine loses power to where it will
only go walking speed. The check engine light has never come on.
Spark voltage remains good. I found that the fuel press. regulator
fuel ports were all clogged up with black hard deposits, like narrowed
down to a pencil- lead size. I cleaned out the ports and checked it
for operation with a vacuum tester. But This did not fix the problem.
So I checked the control vacuum to it. ZERO. At idle, or at high
speed...zero. Then I checked the input hoses (two) and output hose on
EGR valve...zero. so I put the vac gauge on the P-E-R ports at the
throttle body....all three are zero. There is no vacuum either at
idle or at high RPM. SO it is no wonder it is so screwed up. I
believe these three ports are the source of vacuum for the entire
control system, aren't they? How can all three be plugged?
Do they all join inside the throttle body and are fed by one source
(I guess it is something like a venturi)? I guess next step is to
remove the throttle body (hope the Haynes explains this!) Maybe it
needs to be sprayed out with Berrymans' B-12 chemtool to unclog them?
It is a new gauge, so I sucked very gently on the end of the test
hose, just to make sure it is working. Its a good gauge! thanks
geronimo
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Old 11 Aug 2006, 11:46 pm   #2 (permalink)
johngdole@hotmail.com
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Default Re: '88 3SFE engine: no vacuum ANYWHERE!

Your engine is running excessively rich and choking everything with
carbon. What's the maintenance like on this car? Timing belt, plugs,
gaskets, EGR valve cleaning, etc?

Are you getting power brake boost? If so your engine is generating
vacuum, just not getting to the small ports. If you clean the P-E-R
ports (I mean run a wire and see it physically come through) and still
not get any vacuum then you have a serious leak somewhere. I'd think
you'll get low vacuum, but NO vacuum? Check all gaskets, cam/crank
seals, etc for inexpensive starters.


geronimo wrote:
> Its an '88 Camry with 4 cyl. 3SFE engine. I have been trying to figure
> out what is causing an extreme loss of power when the car is driven
> just a short ways. Idling, sitting still, it will run just fine.
> After driving a short ways the engine loses power to where it will
> only go walking speed. The check engine light has never come on.
> Spark voltage remains good. I found that the fuel press. regulator
> fuel ports were all clogged up with black hard deposits, like narrowed
> down to a pencil- lead size. I cleaned out the ports and checked it
> for operation with a vacuum tester. But This did not fix the problem.
> So I checked the control vacuum to it. ZERO. At idle, or at high
> speed...zero. Then I checked the input hoses (two) and output hose on
> EGR valve...zero. so I put the vac gauge on the P-E-R ports at the
> throttle body....all three are zero. There is no vacuum either at
> idle or at high RPM. SO it is no wonder it is so screwed up. I
> believe these three ports are the source of vacuum for the entire
> control system, aren't they? How can all three be plugged?
> Do they all join inside the throttle body and are fed by one source
> (I guess it is something like a venturi)? I guess next step is to
> remove the throttle body (hope the Haynes explains this!) Maybe it
> needs to be sprayed out with Berrymans' B-12 chemtool to unclog them?
> It is a new gauge, so I sucked very gently on the end of the test
> hose, just to make sure it is working. Its a good gauge! thanks
> geronimo


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Old 12 Aug 2006, 10:04 am   #3 (permalink)
Daniel
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Default Re: '88 3SFE engine: no vacuum ANYWHERE!

geronimo wrote:
> How can all three be plugged?
> Do they all join inside the throttle body and are fed by one source

============
The vacuum ports on the throttle body are separate. They port vacuum at
different degrees of throttle opening.
If you just changed the timing belt, double check to make certain the
valve timing is correct. If you're one tooth off, you could be losing
vacuum.

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Old 12 Aug 2006, 12:18 pm   #4 (permalink)
johngdole@hotmail.com
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Default Re: '88 3SFE engine: no vacuum ANYWHERE!

Yes, the E and R port vacuums are proportional to the throttle opening
and they control the EGR modulator. You'll get increasing vacuum
readings at first the E and then the R port with throttle plate opening
up to full engine vacuum.

But there should always be full engine vacuum at the P port, as well as
the brake booster port, or the PCV hose.


Daniel wrote:
> geronimo wrote:
> > How can all three be plugged?
> > Do they all join inside the throttle body and are fed by one source

> ============
> The vacuum ports on the throttle body are separate. They port vacuum at
> different degrees of throttle opening.
> If you just changed the timing belt, double check to make certain the
> valve timing is correct. If you're one tooth off, you could be losing
> vacuum.


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Old 12 Aug 2006, 12:43 pm   #5 (permalink)
Jason James
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Default Re: '88 3SFE engine: no vacuum ANYWHERE!


<geronimo> wrote in message
news:7vkpd21gu854i9j54n9t8io4moqvp87oge@4ax.com...
> Its an '88 Camry with 4 cyl. 3SFE engine. I have been trying to figure
> out what is causing an extreme loss of power when the car is driven
> just a short ways. Idling, sitting still, it will run just fine.
> After driving a short ways the engine loses power to where it will
> only go walking speed. The check engine light has never come on.
> Spark voltage remains good. I found that the fuel press. regulator
> fuel ports were all clogged up with black hard deposits, like narrowed
> down to a pencil- lead size. I cleaned out the ports and checked it
> for operation with a vacuum tester. But This did not fix the problem.
> So I checked the control vacuum to it. ZERO. At idle, or at high
> speed...zero. Then I checked the input hoses (two) and output hose on
> EGR valve...zero. so I put the vac gauge on the P-E-R ports at the
> throttle body....all three are zero. There is no vacuum either at
> idle or at high RPM. SO it is no wonder it is so screwed up. I
> believe these three ports are the source of vacuum for the entire
> control system, aren't they? How can all three be plugged?
> Do they all join inside the throttle body and are fed by one source
> (I guess it is something like a venturi)? I guess next step is to
> remove the throttle body (hope the Haynes explains this!) Maybe it
> needs to be sprayed out with Berrymans' B-12 chemtool to unclog them?
> It is a new gauge, so I sucked very gently on the end of the test
> hose, just to make sure it is working. Its a good gauge! thanks
> geronimo


There are varying levels of vacuum, dependent from where in the intake
system the vac is being sourced from. Manifold or below the throttle-valve
vac is the highest. The brake-booster uses maximum vac from the here. Other
parts of the engine use lessor vacuum and may give you the wrong impression
if its not registering on a gauge designed to indicate max-vac.

Engine vacuum is highest during run-down from high revs (throttle-valve
shut) and at idle. During wide open throttle (WOT) eg during accelerating,
vacuum takes a big dive and is the reason the power-brakes has a resevoir
incorporated into its diaphragm chamber. It also means you need a one-way
valve in the booster vac-line to the booster to stop stored vac from
bleeding back into the intake during low vac engine operation.

If the brake-booster has a ruptured diaphragm, the engine will run rough and
power assist will be reduced. In this case you can usually hear a hissing
sound inside the cabin, coming from the power booster.

If your brakes work fine (the brake pedal should fall slightly after engine
start), its not likely there is a severe vac loss problem, but all the same,
you need to check all the small vac hoses for splitting etc

The PCV valve can cause engine performance problems if it is stuck open.
Test it by plugging the PCV line temporarily at the end which accesses the
cam-cover. Apart from that, you maybe looking at ignition or fuel pressure
problems. Is the air-cleaner OK?

Jason


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Old 12 Aug 2006, 03:40 pm   #6 (permalink)
geronimo
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Default Re: '88 3SFE engine: no vacuum ANYWHERE!



Air filter is new. I took off the throttle body and used Berryman
B12 and shop air on the P-E-R ports. Now that the engine is back
together, I realized there is a capped port on the back side of the
manifold, just made for tests. So I checked it there at idle and it is
20 in. vac. So I then checked the P vac. by connecting the gauge up
to the P line where it attaches to the temp. controlled vacuum
switch. As it should be, there is 20 in vac there also. And that
switch is switching the vacuum on when the engine gets up to temp.
That vac switch is for the evaporative canister I think. The E port
very slowliy goes from zero to about 5 in. as engine is revved. I
believe that particular port is very restrictive, unlike the P
port...hopefully it is supposed to be! The R port goes from about 0 to
10 in. quickly as the engine is revved.
With the fuel press controller vac line connected, I have only
about 37 psi on the fuel line between the engine and the fuel filter
at idle. As a test to see if the fuel press controller was doing
anything at all, I pulled the vac line off, and RPM increased a bit.
The fuel pressure gauge went from 37 toi 45 psi. So with the vac
control line pulled off and capped, I think this just sets the
pressure controller so that it bypassing the least amount of fuel,
raising the press to max.

The brakes work great, no hissing sound, so I think they must be
getting normal vacuum.

The main thing I need to know is if that vac press. in the intake
manifold is normal.....or low, indicating I have a vac. leak
somewhere.

Should I look at the EGR system? THey look like they could be the
original parts with nearly 200K moiles on them. Could this cause a
sudden loss of power, slowing down to a crawl after driving some
miles?
Will definitely check the PCV valve out!

At least my oil pump, water pump and timing belt change went well, and
it is no longer leaking a drop of oil anywhere or leaking any coolant
either.


THe other issue I have is with the fan control switch. I found the
original bad, had a pinhole leak in the bulb, and so it had stopped
switching...it was just stuck grounded, and this keeps the fan off.
Well I went and bought a new one from Autozone. Install it and I have
the same problem...the fan never turns on at normal temps. I had to
again pull the connector off to get the fan to run. So I checked the
new switch by immersing it in boiling water. Yes, at 212 deg. the
switch does open, so it is functional. but isn't the fan switch
supposed to turn fan on at around 185-190 deg? The car will sit there
idling in hot summer weather, and it never turns the fan on!

Thanks, Geronimo


thanks, Geronimo




On Sat, 12 Aug 2006 17:43:20 GMT, "Jason James" <home@work.1.0> wrote:

>
><geronimo> wrote in message
>news:7vkpd21gu854i9j54n9t8io4moqvp87oge@4ax.com.. .
>> Its an '88 Camry with 4 cyl. 3SFE engine. I have been trying to figure
>> out what is causing an extreme loss of power when the car is driven
>> just a short ways. Idling, sitting still, it will run just fine.
>> After driving a short ways the engine loses power to where it will
>> only go walking speed. The check engine light has never come on.
>> Spark voltage remains good. I found that the fuel press. regulator
>> fuel ports were all clogged up with black hard deposits, like narrowed
>> down to a pencil- lead size. I cleaned out the ports and checked it
>> for operation with a vacuum tester. But This did not fix the problem.
>> So I checked the control vacuum to it. ZERO. At idle, or at high
>> speed...zero. Then I checked the input hoses (two) and output hose on
>> EGR valve...zero. so I put the vac gauge on the P-E-R ports at the
>> throttle body....all three are zero. There is no vacuum either at
>> idle or at high RPM. SO it is no wonder it is so screwed up. I
>> believe these three ports are the source of vacuum for the entire
>> control system, aren't they? How can all three be plugged?
>> Do they all join inside the throttle body and are fed by one source
>> (I guess it is something like a venturi)? I guess next step is to
>> remove the throttle body (hope the Haynes explains this!) Maybe it
>> needs to be sprayed out with Berrymans' B-12 chemtool to unclog them?
>> It is a new gauge, so I sucked very gently on the end of the test
>> hose, just to make sure it is working. Its a good gauge! thanks
>> geronimo

>
>There are varying levels of vacuum, dependent from where in the intake
>system the vac is being sourced from. Manifold or below the throttle-valve
>vac is the highest. The brake-booster uses maximum vac from the here. Other
>parts of the engine use lessor vacuum and may give you the wrong impression
>if its not registering on a gauge designed to indicate max-vac.
>
>Engine vacuum is highest during run-down from high revs (throttle-valve
>shut) and at idle. During wide open throttle (WOT) eg during accelerating,
>vacuum takes a big dive and is the reason the power-brakes has a resevoir
>incorporated into its diaphragm chamber. It also means you need a one-way
>valve in the booster vac-line to the booster to stop stored vac from
>bleeding back into the intake during low vac engine operation.
>
>If the brake-booster has a ruptured diaphragm, the engine will run rough and
>power assist will be reduced. In this case you can usually hear a hissing
>sound inside the cabin, coming from the power booster.
>
>If your brakes work fine (the brake pedal should fall slightly after engine
>start), its not likely there is a severe vac loss problem, but all the same,
>you need to check all the small vac hoses for splitting etc
>
>The PCV valve can cause engine performance problems if it is stuck open.
>Test it by plugging the PCV line temporarily at the end which accesses the
>cam-cover. Apart from that, you maybe looking at ignition or fuel pressure
>problems. Is the air-cleaner OK?
>
>Jason
>


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Old 12 Aug 2006, 05:39 pm   #7 (permalink)
geronimo
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Default Re: '88 3SFE engine: no vacuum ANYWHERE!



Now it has a much worse problem. It is over- heating. When I was
working on the throttle body, I bumped the temp sensor (the gauge
sender), and knocked the contact part off. So I had to remove the part
where the radiator hose, and sensor and vacuum switches are mounted. I
installed a new sensor, and remounted the assembly on the engine with
the two nuts. That is all I did. I thought that perhaps the
calibration of the new sensor was not the same as old one, but I
checked the engine temps with a laser temp gauge when it was edging up
towards the red zone, and it was at 225 deg. ! Shut it off real quick!
The sensor was not quite the same, the sensor body is a little longer
than original, but don't see how this would cause some major
restriction of water flow. The radiator is topped off and cooling
system is not leaking a bit...not even at 225 deg.

Before working on throttle body and changing the temp sensor, it was
running at mid-scale on temp gauge as it should. There is only one
fan coming on, the one on the right side, but it is apparently
adequate (when all is normal) enough by itself, it seems. Or should
both come on ?
From the Haynes manual, I think the RH side one is supposed to be
turning on with the A/C....but it is the RH one that is being
controlled by the fan control switch on the thermostat housing. The AC
isn't working yet, not charged, so I would guess that is why one fan,
in my case the LH one...is never coming on.

IF only I was rich and could just take it to an auto repair shop. ;-)

Geronimo
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Old 13 Aug 2006, 12:01 am   #8 (permalink)
johngdole@hotmail.com
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Default Re: '88 3SFE engine: no vacuum ANYWHERE!


geronimo wrote:
>The E port
> very slowliy goes from zero to about 5 in. as engine is revved. I
> believe that particular port is very restrictive, unlike the P
> port...hopefully it is supposed to be! The R port goes from about 0 to
> 10 in. quickly as the engine is revved.


I think the vacuums there are a little low, even with the tiny ports.
You should be getting near full manifold vacuum, which you stated is
about 20in. So you are getting vaccum from the engine, and pretty
health at that, 17-22 normally.

> Should I look at the EGR system? THey look like they could be the
> original parts with nearly 200K moiles on them. Could this cause a
> sudden loss of power, slowing down to a crawl after driving some
> miles?


EGR is a simple system that really doesn't go bad except they get
plugged up with carbon and stick either open or shut. Do a simpel test:


First measure the vacuum at the EGR port hose. You should get 0 (no
vacuum) at idle. If you get vacuum at idle at the valve, you have a
problem. Also pull vacuum of the EGR valve and see if the engine runs
rough or stalls. If so, it's ok. If no change then the valve is not
working.


> At least my oil pump, water pump and timing belt change went well, and
> it is no longer leaking a drop of oil anywhere or leaking any coolant
> either.


Let's see: your upper rad hose gets hot and then the lower get warm to
hot? If so your thermostat is opening and your water pump is working.
Because if hot water isn't coming out into the radiator, your fan
switch isn't going to turn the fan on (while at the same time your
engine overheats because hot water stays there).

So your fan is working as you bypassed the switch. At least that's
good. The two coolant fan switches operate at different termperatures.
Usually 20 def-F apart. If one is at 185 then the other is at 205. The
higher one switches on the condenser fan if it's not on already because
of the AC.


> Well I went and bought a new one from Autozone. Install it and I have
> the same problem...the fan never turns on at normal temps. I had to
> again pull the connector off to get the fan to run. So I checked the
> new switch by immersing it in boiling water. Yes, at 212 deg. the
> switch does open, so it is functional. but isn't the fan switch
> supposed to turn fan on at around 185-190 deg? The car will sit there
> idling in hot summer weather, and it never turns the fan on!
>
> Thanks, Geronimo
>


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Old 13 Aug 2006, 12:13 am   #9 (permalink)
johngdole@hotmail.com
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Default Re: '88 3SFE engine: no vacuum ANYWHERE!

You should probably first check coolant flow:

- Water pump (is the right pump installed? is the timing belt properly
tensioned? etc
- Thermostat. (is it operning and the valve opening height within
spec?)

The new coolant sensor: is it spec'ed for 1988 3SFE? If so, physical
apperance may change over the years. What's important is the
temperature response:

See Figure 1, Autozone's free repair guide:
http://www.autozone.com/servlet/UiBr...3d8013e283.jsp

BTW, the guide implied the 3SFE has only 1 level of fan switching, at
199 deg-F only. Then the AC fan is controlled by turning the AC on
only. I am not sure about this.


geronimo wrote:
> Now it has a much worse problem. It is over- heating. When I was
> working on the throttle body, I bumped the temp sensor (the gauge
> sender), and knocked the contact part off. So I had to remove the part
> where the radiator hose, and sensor and vacuum switches are mounted. I
> installed a new sensor, and remounted the assembly on the engine with
> the two nuts. That is all I did. I thought that perhaps the
> calibration of the new sensor was not the same as old one, but I
> checked the engine temps with a laser temp gauge when it was edging up
> towards the red zone, and it was at 225 deg. ! Shut it off real quick!
> The sensor was not quite the same, the sensor body is a little longer
> than original, but don't see how this would cause some major
> restriction of water flow. The radiator is topped off and cooling
> system is not leaking a bit...not even at 225 deg.
>
> Before working on throttle body and changing the temp sensor, it was
> running at mid-scale on temp gauge as it should. There is only one
> fan coming on, the one on the right side, but it is apparently
> adequate (when all is normal) enough by itself, it seems. Or should
> both come on ?
> From the Haynes manual, I think the RH side one is supposed to be
> turning on with the A/C....but it is the RH one that is being
> controlled by the fan control switch on the thermostat housing. The AC
> isn't working yet, not charged, so I would guess that is why one fan,
> in my case the LH one...is never coming on.
>
> IF only I was rich and could just take it to an auto repair shop. ;-)
>
> Geronimo


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Old 13 Aug 2006, 07:39 am   #10 (permalink)
geronimo
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Default Re: '88 3SFE engine: no vacuum ANYWHERE!





John, would the cooling fan switch for the second fan be on top of
that header (or whatever is called) mounted on the left side of
engine, the same header that the top radiator hose goes to, and has
two temp-controlled vac switches and the gauge sensor ? There is on
the top side of it another switch or sensor that has a two-conductor
connector...its not like the fan switch on the thermostat housing that
has a single conductor. I am asking because I need to locate and
check the other fan switch, see if it is bad also.

The thermostat is a new one and is known to open fully, and as I said,
after initial test runs after replacing timing belt, water pump, oil
pump, was maintaining the engine temp gauge at mid-scale. It is only
after checking throttle body and changing out gauge sensoro that it
has the over heat problem.

Could the timing have jumped? Would this cause overheat possibly? Yet
engine power has not changed a bit, nor idle speed.

Autozone apparenty gave me the fan temp switch that actuates at the
higher temp! They can't tell you what the specs are for any electrical
part, that is the problem with Wells/ Autozone parts. No specs are
included in the box with the part! But I think the same is true of
internet vendors....no specs. So I guess I am out $35 for an
incorrect part that they don't accept returns on as it is now used.

I didn't really have to bypass anything to get the RH fan running...I
just leave it unplugged from the new fan switch. Funny thing is
that I pulled both fan control relays...yet the fan still contines to
run! Have to pull the CDS fuse to get it to stop. I am having lots
of trouble with this, partly because I am an ameteur, and also because
the wiring diagram in the Haynes manaual is just a generic one
covering several model years, and on my car is not the same as shown.
The diagram doesn't show two fan temp switches, it shows the AC fan as
only controlled by a relay.

Thanks, Jim


Also, please clarify which vacuum port should not have vacuum at idle.
There are ports /hoses on the modulator and on the EGR valve itself.

I do know that there is no vacuum signal to the vac. control port on
the top of the EGR valve, and nothing changes when I
connect/disconnect it.



Thanks, Jim


On 12 Aug 2006 22:01:03 -0700, johngdole@hotmail.com wrote:

>
>geronimo wrote:
>>The E port
>> very slowliy goes from zero to about 5 in. as engine is revved. I
>> believe that particular port is very restrictive, unlike the P
>> port...hopefully it is supposed to be! The R port goes from about 0 to
>> 10 in. quickly as the engine is revved.

>
>I think the vacuums there are a little low, even with the tiny ports.
>You should be getting near full manifold vacuum, which you stated is
>about 20in. So you are getting vaccum from the engine, and pretty
>health at that, 17-22 normally.
>
>> Should I look at the EGR system? THey look like they could be the
>> original parts with nearly 200K moiles on them. Could this cause a
>> sudden loss of power, slowing down to a crawl after driving some
>> miles?

>
>EGR is a simple system that really doesn't go bad except they get
>plugged up with carbon and stick either open or shut. Do a simpel test:
>
>
>First measure the vacuum at the EGR port hose. You should get 0 (no
>vacuum) at idle. If you get vacuum at idle at the valve, you have a
>problem. Also pull vacuum of the EGR valve and see if the engine runs
>rough or stalls. If so, it's ok. If no change then the valve is not
>working.
>
>
>> At least my oil pump, water pump and timing belt change went well, and
>> it is no longer leaking a drop of oil anywhere or leaking any coolant
>> either.

>
>Let's see: your upper rad hose gets hot and then the lower get warm to
>hot? If so your thermostat is opening and your water pump is working.
>Because if hot water isn't coming out into the radiator, your fan
>switch isn't going to turn the fan on (while at the same time your
>engine overheats because hot water stays there).
>
>So your fan is working as you bypassed the switch. At least that's
>good. The two coolant fan switches operate at different termperatures.
>Usually 20 def-F apart. If one is at 185 then the other is at 205. The
>higher one switches on the condenser fan if it's not on already because
>of the AC.
>
>
>> Well I went and bought a new one from Autozone. Install it and I have
>> the same problem...the fan never turns on at normal temps. I had to
>> again pull the connector off to get the fan to run. So I checked the
>> new switch by immersing it in boiling water. Yes, at 212 deg. the
>> switch does open, so it is functional. but isn't the fan switch
>> supposed to turn fan on at around 185-190 deg? The car will sit there
>> idling in hot summer weather, and it never turns the fan on!
>>
>> Thanks, Geronimo
>>


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