91ES2502

Hi,

I recently went from being out-of-country to being back in the States, and then traded an unlocked 300 dollar TMOBILE LG D520/F3Q for a Lexus. The Lexus looks like in Fair condition it would have a value of 414, if it was a '95. The BlueBook website only goes back that far...

It definitely has a cam seal leak. The 'deluxe' kit with all the gaskets / seals is 65 bucks from OReilly (Felpro). I've been dumping a litre of oil in it every couple of weeks. It started two quarts low... the previous owner was not so up on basic car maintenance.

If anyone wants to contribute what the car should need... it's got 243k miles on it. The startup exhaust smells a bit benzine rich but not offensive. ["I prefer the 91," ]

It needs also the Thermostat switch replaced. I've looked around; it looks like from web pages and videos, that the Camry-based engine in it, has the switch on the bottom of the radiator. However, when we went to replace the radiator cap about a month ago (not my car, yet), the one that matched up was for an LS model. I am going to crawl under there today. If I have to drop the fluid I will do that, and replace the plug-type sensor switch. The symptom is the fans run all the time. I pull the engine relay to shut off the fans until the car is warmed up, however performance is laggy etc, and probably gas milage takes a hit.

The belt on the left looks okay. I'm thinking these seals failed recently, and that the whole car was in good shape as of 200k miles.

Plugs, wires.
Seals, cam.
Thermostat sensor switch.
Change oil, filter.
Checked the auto transmission fluid, colour looks good.
These fans were running all the time, keeping the components cool in the hot Montana summers. So I'm thinking they did good being running all the time, keeping the alternator etc cool. I've put a manual override on a couple of Nissan cars that had a tendency to run hot, so at least one fan could be kept on the whole time during hot months.

Suggestions?


Update:
I can't find the location of the thermostat sensor switch. Anyone?
I guess the previous mechanics couldn't either. When I got it initially, the Engine Relay (fans) had been pulled and replaced with a wire that ran inside the firewall, providing the 30amps to the fans through the fuse box. Needless to say, that wasn't functional. The wire would overheat. The switch eventually fried. It has the correct relay in there now, but the fans are stuck on.

Update 2:
http://www.turboninjas.com/camry/
These are coming in handy
Lexus Specific
1991_Lexus_ES_250_FSMs.zip = 1991 ES250 FSM ------------------------- [13.2Mb]

jltait

Not being familiar with the 1st generation ES, I recommend you head over to the ToyotaNation forum. I think you'll have more luck there looking up the v6 Camry of the same model year.

You did well on that trade. In its time, that was quite an important sedan. Enjoy your Lexus!

LeX2K

The thermostat is under the alternator, the radiator fan switch is also there on the thermostat housing. There is an electronic controller behind the glove box that uses that sensor to turn the fans on and off. Your engine is exactly the same as what's in the Camry EXCEPT the valve covers are different as are the spark plug wires so keep that in mind.

The cam seals love to leak on the 2VZ-FE so definitely replace those and if the timing belt is at or near in need of replacing then do that and the crank seal at the same time, along with the water pump and idler/tensioner.

91ES2502

Thanks! That's tremendous support.

Before getting to check back to the forum, I got to page 156 of the Wiring manual, which shows W3, the fan sensor you talk about. And refers back to page 27, which shows it being ... somewhere .. and yes I eventually saw it underneath the alternator. The part given to me by OReilly's personnel does not match.

Further, the boot was not connected to the sensor, and of the white and yellow wire leads, the yellow wire jacket was abraded by the alternator belt. I relaxed the alternator tension and swung the bar away, to pull the lead out and will repair it. It is not broken, only abraded with about 1cm of shielding missing.

So, hooking up the sensor boot before I did that, changed nothing. The fans continue to operate at what seems like high speed as soon as I turn the key to the Run position.

From the reference above, the fans should not be turning at all. The car is stone cold and the ambient temp is below freezing. AC button is off.

image from page 156 (153 PDF) of the wiring manual converted by pdf2jpg.net (free)

The question is, what should I start checking?
I have a multimeter also. Hopefully it works after the overseas ride.

What should the resistance of the water temp sensor be when cold?

Addition:
Found this: http://www.ebay.com/itm/TOYOTA-CAMRY...-/370574606805
for a kit. What do you think also, about this? The last service sticker on the timing belt reads 137k miles. :/
Update 3:
From http://forums.travel.com/toyota-camr...ml#post1675759

91ES2502

Diagram of where some of the (maybe faulty) fan control relays are located.

LeX2K

The sensor on the 'stat housing could be faulty check the service manual on how to test it. Another source of failure is definitely the fan relays, as shown in the info you posted when they go bad the fans always spin this is a fail safe design.

91ES2502

Is that the sensor underneath the alternator from earlier? Does it fail in the open position? If so, it should be reading hot (open) when the engine is cold. It shows only as a resistor, and not a switch, in the diagram.

I just got done pulling and checking all three fan relays since the last post. All of them are working correctly. I supplied 12v across the coils and measured each contact point according to what the relay is supposed to read with and without the coil energized. They all function.

Update:

I looked all over the wiring manual. There are service hints organized on a few pages for that section of the car dealing with the fans and a/c, with values of resistance for various components. But the sensor is not listed among them. It is conspicuously absent.

What would be the effect of unplugging the sensor? I would assume that makes the fans always run (failsafe), increasing the resistance across the two contacts to infinity (open circuit). However, http://www.camryforums.com/forum/ecu...724/#post83833

the link above has:

So, if it is the same for the 91 Camry mentioned, I should be faking infinite resistance/cold readings from the sensor by having the connector to it pulled.
That's how I found it when I went looking for the temp sensor, with the connector completely off.

LeX2K

Yes. It's not a switch it's a thermistor which is a temperature dependent resistor. If there is no resistance (open circuit) the fans will always spin, so if you have continuity on the sensor that means there is a wiring problem preventing power from going to the fan relay. To find out which relay, with the ignition on pull the fan relays until the fans stop. That will be the one that is not getting power. I think it will be the one nearest the firewall but not certain.

IIRC that relay gets power fed through the A/C high pressure switch so if there no continuity in that circuit the fans will always be on.


.....edit..... look at page 200 of the Engine.pdf file.

91ES2502

I looked at page 200 of the Engine FSM pdf but couldnt make any sense of it yet.

These are the test results:
The relay labeled Radiator Fan Relay No. 1, on the top-right of page 20, closest to the firewall in the box on the front left of the vehicle under the hood, when I pull it the left (radiator, larger) fan turns off.

When I pull the one labelled A/C Fan Relay No. 2, the right fan turns off.

When I pull A/C Fan Relay No. 3, nothing happens, both fans continue to run on high.

Testing the resistance across the two connectors on the W 3 Water Temp Sensor (Fans) - it was tricky, a very small area to use normal MM probes on - shows no resistance with the engine cold (has not turned over all day and last night, and is sitting outside in freezing temps).

Shorting the two connections on the probe connection, the white/yellow wires, changes nothing. Fans continue to run on high.

The above is confusing. According to the information from the 91 Camry on a 4cyl, the style of sensor should be the same as here.
As noted on the other forum, according to the Denso and Yazaki brands posted, the resistance goes down on high temps. Yet this sensor is reading no resistance at freezing. So if the sensor is bad, if I pull the lead, the A/C Condenser Fan Control Amplifier (A 14) should energize the coils, turning off the fans. ??

Confusing bits below:
"No resistance (open circuit)." No resistance is a closed circuit, not open. I think that's what you intended. "Continuity on the sensor" would also be a closed circuit, which is what you wrote.

So>
The sensor appears to have no resistance, so whether it is working or not, if I pull the plug and leave it off, it should simulate a COLD condition, that should be sending an 'open circuit' message (coolant is cold) to the A14 A/C Condensor Fan Control Amplifier, which should then be sending power to the Fan Relay through S 1 Short Pin (For Fan Check) then A 9 A/C High Pressure Switch (For Radiator Fan) to the coils on Radiator Fan Relay No. 1 and A/C Relay Fan No. 2, assuming the continuation of the wiring is functional and 7. 5A IGN is intact.

I feel like we are getting somewhere.

Update:
Fixed the references above to the sensor circuit being open/closed. Apparently the sensor is supposed to register high resistance when the coolant is cold, simulating an open circuit. Apparently that is an industry standard Toyota did go with. It's reversed only on the control side, the relay circuit, where energizing means to turn the fans off. The sensor loop works though like an ordinary car.

Further, I checked the A 9 A/C High Pressure Switch (For Radiator Fan) and the S 1 Short Pin (For Fan Check). Both are in good condition. The A 9 Pressure Switch registers closed, and the S 1 Short Pin is simply a connector. It's purpose is to be pulled out, to lose power to the relay coils, thereby causing both fans to turn on, but the fans are already on because relays are not firing, the circuit is not being energized.

91ES2502

So if the circuit energized on connection #4, inside the glovebox on the A 14 A/C Condenser Fan Control Amplifier turns off the fans, all the other components that carry power to the relays, including the relays themselves, check out.

Tomorrow I can unplug A 14, and run connector pin 4, the brown wire that goes into A 14, to ground. That should energize and complete the circuit and cause the fans to turn off.

Then run a multi-meter across the Purple/LightGreen wires of 7&5 into A 14. I will measure the sensor resistance from within the firewall, to see if it is changing as the car warms up. It should start out high, then go low when hot.

91ES2502

After coffee and breakfast, these are the results!

Thinking about this> http://www.ebay.com/itm/TOYOTA-CAMRY...-/370574606805
That kit plus plugs, wires, cam cover seals, the sensor..

To prior owner/operator: Q: When is the last time you had the water pump replaced?
Doesn't know. "If something went wrong" I took it in. And they "did stuff".


The car started 3 yrs ago with 200k. The timing belt label on the cover says 137k miles.
Need I say more?
....

So, this morning I started by fixing the insulation on the wire leading to the W 3 Water Temp Sensor No. 1 (For Fans), tightened the alternator and plugged everything back in. Looking further in the glove box, A 14 A/C Condenser Fan Control Amplifier was UNPLUGGED (see photo). I tested it with the W 3 and A 14 plugged in. Same - fans on high. I unplugged A 14 and tested with a MM the resistance across terminals 7&5 with the W 3 sensor plugged in: 003 ohms (short condition, circuit closed). Unplugged showed a reading of infinity. If I clear the earwax out, what you guys here and on the TN board are saying, is:

If that sensor is not within spec, the fans run. That the sensor has to have some resistance level for the computer A 14 to operate the fans at anything other than high (fail-safe).

Also, I ran a ground clip from the frame to pin 4, and was successfully able to turn the fans off. And toggle them several times by disconnecting and reconnecting the clip to ground.

The part from O'Reillys is wrong, otherwise I would have swapped it in by now. I'm outside of town. Thanks for the warnings about blowing the head gasket if the car gets too hot. At least now I can toggle the fans from inside the car, by clipping the lead to ground (laughing so hard).

When going through the OReilly's catalogue, it comes up with that same wrong part, so something is wrong with their catalogue.

There are a lot of sensors on the RockAuto catalogue for the same application

Which one do I get?

Related post on ClubToyota (ToyotaNation) http://www.toyotanation.com/forum/10...ml#post8329721


< What is that?

91ES2502

I can't find the sensor in their catalogue or OReilly's

Here is the list. Please suggest anything else. Car has 243k miles.

Belt Drive : Belt
GATES Part # K030310 **#25030310, 2570787} K03 13/32" x 31-5/8" Micro-V AT Premium OE V-Ribbed Belt [Wholesaler Closeout - Private Label Pkg. - 30 Day Warranty] (Only 9 Remaining)Power Steering Belt; w/POWER STEERING C
Do you also need a Belt Installation Tool?
$3.24 $3.24 Remove Part

GOODYEAR Part # 4060415 6 Ribs / Effective Length 41.5" / Outside Length 42.25" Gatorback [Wholesaler Closeout -- 30 Day Warranty] (Only 12 Remaining)
Alternator and Air Conditioning; Poly-V C
Do you also need a Belt Installation Tool?
$5.88 $5.88 Remove Part

Brake/Wheel Hub : Brake Pad
RAYBESTOS Part # SGD356M **#RPD356, RPD356M} Service Grade - Semi-Metallic [Wholesaler Closeout - Private Label Pkg. - 30 Day Warranty] (Only 6 Remaining)
Front; OE PAD MATERIAL IS ORGANIC C
$6.02 $6.02 Remove Part

Brake/Wheel Hub : Brake Pad Shim Kit
RAYBESTOS Part # DS8037 Professional Grade [Wholesaler Closeout -- 30 Day Warranty] (Only 1 Remaining)
Anti Squeal Kit C
$1.36 $1.36 Remove Part

Cooling System : Water Pump
AISIN Part # TKT012 Engine Timing Belt Kit with
Hydraulic Tensioner: Included B
Do you also need a Water Pump Wrench?
Get the whole job done at once by purchasing a Timing Belt Component Kit including the water pump.
$146.79 $146.79 Remove Part

Emission : Oxygen Sensor
BECK/ARNLEY Part # 1562014 [Wholesaler Closeout -- 30 Day Warranty]
Upstream; OEM # 89465-32120 C
An Oxygen Sensor Socket / Wrench can make removal and installation of this part easier.
$18.74 $18.74 Remove Part

Fuel/Air : Fuel Filter
PUROLATOR Part # F40263 [Wholesaler Closeout - Private Label Pkg. - 30 Day Warranty]
$2.59 $2.59 Remove Part

Ignition : Spark Plug
BOSCH Part # 9603 OE Fine Wire Iridium; Single Electrode; Do not Gap- Gap is preset
+ Sold in packs of 4; Price reflects cost of each individual item, not the pack E
$5.01 $20.04 Remove Part

BOSCH Part # 9603 OE Fine Wire Iridium; Single Electrode; Do not Gap- Gap is preset
$5.16 $10.32 Remove Part

Ignition : Spark Plug Wire
NGK Part # 9974
0.044 D
$13.17 $13.17 Remove Part

Ignition : Distributor Cap
STANDARD MOTOR PRODUCTS Part # JH143 **#12351073, 1910162020, 1910162030, E354A} Intermotor [Wholesaler Closeout -- 30 Day Warranty] (Only 7 Remaining)
$6.91 $6.91 Remove Part

Ignition : Distributor Rotor
AIRTEX / WELLS Part # 4R1141 **#12353031, 1910262020, JA979} O.E. Replacement [Wholesaler Closeout -- 30 Day Warranty] (Only 7 Remaining)
$2.61 $2.61 Remove Part

Transmission-Automatic : Filter
PIONEER Part # 745113 (Only 19 Remaining)
Trans. code A540E A
$7.59 $7.59 Remove Part

Engine : Crankshaft Seal
TIMKEN Part # 224020 **#018710507, 018710507B, 1304201M00, 23121205340, 8970233730, 9008031034, 9031140006, 9031140013, 9031140022}
Front; O.E. A
$3.95 $3.95 Remove Part

Engine : Camshaft Seal
BECK/ARNLEY Part # 0523591 **#2118568, 9008031035, 9008031055, 9031138034, 9031138051} (Only 12 Remaining)
+ Sold in packs of 2; Price reflects cost of each individual item, not the pack C
$4.15 $8.30 Remove Part

Total: 257.51