Pinging
07-01-2004, 11:15 AM
#76
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>Now the temp guage rises slowly to above the 9:00 pm line and pretty much hovers around 9:00 pm no matter what.
Oh yeah. If it stays above 9:00, even when on the freeway (natural airflow), sounds like a failed thermostat (verify your fender is getting warm). If it's only staying above 9:00 when stuck in traffic, this would be a fan issue.
Oh yeah. If it stays above 9:00, even when on the freeway (natural airflow), sounds like a failed thermostat (verify your fender is getting warm). If it's only staying above 9:00 when stuck in traffic, this would be a fan issue.
07-01-2004, 11:24 AM
#77
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Jon,
[Edit - Randall beat me to it!
]
What you describe sounds like thermostat behavior, and would seem to be below the temperature region where the oil cooling fan comes into play.
maybe your thermostat is not functioning properly, and is not sending all the oil that it should to the oil cooler?
On my car the cooling fan won't kick on until the temp needle is at least halfway between the second mark and the third mark (where the first mark is a sort of double mark, the second mark is at about the 8:30 clock position, third mark is about the 9:30 position, and fourth mark is red zone). I rarely see sustained temperatures above the second mark unless stuck in slow traffic.
However, I see the thermostat operating all the time.
When cruising (e.g. highway) my temp needle will gradually rise to cover the second mark, and then fall quickly when the thermostat opens to settle roughly midway between the first and second marks. If at highway cruise, there it will stay. In this situation I think the engine produces enough heat to keep the thermostat open, but the oil cooler (with good airflow) is cooling well enough to keep the temperature needle between the first and second marks (since the temp sensor that signals the cockpit gauge samples oil downstream of the oil cooler).
If cruising at lower speeds then sometimes I will notice the needle slowly cycling by gradually rising to the second mark, then falling to midway and repeating as the thermostat opens and closes. If stuck in slow/stopped traffic, then the temp needle will rise above the second mark, and may continue rising until the oil cooling fan checks the rise.
[Edit - Randall beat me to it!
]What you describe sounds like thermostat behavior, and would seem to be below the temperature region where the oil cooling fan comes into play.
maybe your thermostat is not functioning properly, and is not sending all the oil that it should to the oil cooler?
On my car the cooling fan won't kick on until the temp needle is at least halfway between the second mark and the third mark (where the first mark is a sort of double mark, the second mark is at about the 8:30 clock position, third mark is about the 9:30 position, and fourth mark is red zone). I rarely see sustained temperatures above the second mark unless stuck in slow traffic.
However, I see the thermostat operating all the time.
When cruising (e.g. highway) my temp needle will gradually rise to cover the second mark, and then fall quickly when the thermostat opens to settle roughly midway between the first and second marks. If at highway cruise, there it will stay. In this situation I think the engine produces enough heat to keep the thermostat open, but the oil cooler (with good airflow) is cooling well enough to keep the temperature needle between the first and second marks (since the temp sensor that signals the cockpit gauge samples oil downstream of the oil cooler).
If cruising at lower speeds then sometimes I will notice the needle slowly cycling by gradually rising to the second mark, then falling to midway and repeating as the thermostat opens and closes. If stuck in slow/stopped traffic, then the temp needle will rise above the second mark, and may continue rising until the oil cooling fan checks the rise.
07-02-2004, 07:20 AM
#78
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Alright- you guys have me convinced. I ordered the part today. Meanwhile if it gets really hot around here, I may run with the sensor unconnected which should put the car in high-speed blower mode. If it stays mild, I will just wait for the part.
07-03-2004, 07:55 AM
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I ordered the oil temperature sensor...part number 964 624 110 00. Fairly cheap part if it turns out I am wrong.
I think the thermostat is opening. Tonight I drove home on a fairly cool evening....all interstate highway driving. Starting cold, the temp went smoothly up to a bit past the 9pm (194 F) line. Then dropped quickly to a bit below the 9 pm line. Then it slowly rose up to track on or slightly above the 9pm line for the rest of the trip home. I pulled into the garage and got out, and listened for the fan. I heard nothing.
I think the thermostat is opening. Tonight I drove home on a fairly cool evening....all interstate highway driving. Starting cold, the temp went smoothly up to a bit past the 9pm (194 F) line. Then dropped quickly to a bit below the 9 pm line. Then it slowly rose up to track on or slightly above the 9pm line for the rest of the trip home. I pulled into the garage and got out, and listened for the fan. I heard nothing.
03-21-2010, 10:31 PM
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There might be a more recent post so my apologies.
My new to me 964 has begun pinging/knocking/missing under more than 1/3 throttle and earlier today the motor stalled 3x with the a/c on. Let me describe the pinging/knocking/missing as bad...really bad. Interestingly, the check engine light is not on (but it is operational). So far I have:
-pulled the primary distributor vent to visually peep thru the hold and confirm the distributor belt is rotating per other posts here
-hunted for wire arcs with the motor running in the dark
-added a can of octane boost this afternoon
-previous owner installed an SW chip a few months ago rated for 91 RON. I pulled the SW chip, re-installed the factory original...issues persist, reinstalled the SW chip this afternoon
-pulled the secondary distributor cap, noted I could not turn the rotor freely
-later in the day I had my assistant (daughter with a new drivers license) crank the starter and watched as the secondary rotor rotated (sorry) further confirming the dist belt is intact.
-pulled the primary distributor coil wire- interesting- car will not start...
-attempted billwganer's "Retrieving diagnostic codes" but got zero response (possibly due to the chip, unsure)
And then it hit me- the key was when the car would not start with the primary coil wire pulled.
So tonight I disconnected the coil wire from the primary coil and the car starts and idles just fine. Reconnected the primary, disconnected the secondary and no joy. Conclusion- bad primary distributor coil!
And thanks to the RL'r who seems to constantly post "coils and plug wires", etc.
'Don't know the condition of my knock sensors, Hall thingy's, etc, but I'm learning and at this point I'm confident I have one bad coil.
Let me know if it appears I know what I'm doing...
My new to me 964 has begun pinging/knocking/missing under more than 1/3 throttle and earlier today the motor stalled 3x with the a/c on. Let me describe the pinging/knocking/missing as bad...really bad. Interestingly, the check engine light is not on (but it is operational). So far I have:
-pulled the primary distributor vent to visually peep thru the hold and confirm the distributor belt is rotating per other posts here
-hunted for wire arcs with the motor running in the dark
-added a can of octane boost this afternoon
-previous owner installed an SW chip a few months ago rated for 91 RON. I pulled the SW chip, re-installed the factory original...issues persist, reinstalled the SW chip this afternoon
-pulled the secondary distributor cap, noted I could not turn the rotor freely
-later in the day I had my assistant (daughter with a new drivers license) crank the starter and watched as the secondary rotor rotated (sorry) further confirming the dist belt is intact.
-pulled the primary distributor coil wire- interesting- car will not start...
-attempted billwganer's "Retrieving diagnostic codes" but got zero response (possibly due to the chip, unsure)
And then it hit me- the key was when the car would not start with the primary coil wire pulled.
So tonight I disconnected the coil wire from the primary coil and the car starts and idles just fine. Reconnected the primary, disconnected the secondary and no joy. Conclusion- bad primary distributor coil!
And thanks to the RL'r who seems to constantly post "coils and plug wires", etc.
'Don't know the condition of my knock sensors, Hall thingy's, etc, but I'm learning and at this point I'm confident I have one bad coil.
Let me know if it appears I know what I'm doing...
