Uh oh....
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Hi Dave C.,
I met a fellow 928'er around here, he isn't an active internet kinda fellow, but has over 300,000 miles on his OB. He introduced me to a fellow by the name of "Lucky", who told me about the actuator. Said they can be resurrected most times, but often fail at @ 100,000 miles. I'm at 101,258, I've already gotten the manifold off, why not be on the safe side, put a new one in, and try to refurbish the old one at some other time?
"Lucky" pointed me at other items, Rich pointed me at others. A-goin' down the lists....
Thanks for the tips on the other items. I had sprayed WD-40 down the breather line, 4 other times, with no change in my problem. Just don't think I'll take a chance......
( jist a-dodgin' them thar bullits....... )
I met a fellow 928'er around here, he isn't an active internet kinda fellow, but has over 300,000 miles on his OB. He introduced me to a fellow by the name of "Lucky", who told me about the actuator. Said they can be resurrected most times, but often fail at @ 100,000 miles. I'm at 101,258, I've already gotten the manifold off, why not be on the safe side, put a new one in, and try to refurbish the old one at some other time?
"Lucky" pointed me at other items, Rich pointed me at others. A-goin' down the lists....
Thanks for the tips on the other items. I had sprayed WD-40 down the breather line, 4 other times, with no change in my problem. Just don't think I'll take a chance......
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Brett asked about the inlet air temp sensor on the top of the S4 manifold...
>When this sensor fails, will the fans stay off after the car is shut off despite a hot engine? I get this paranoia now that my connectors could be fried because when my car is hot and the fans are running, the fans shut off after I turn off the car instead of staying on.
>So I should be reading infinit ohms.... May I ask where, if it is still used, the intake air sensor is?
The inlet air temp sensor - or, perhaps we should say the intake manifold temp sensor - is a simple off-on thermal switch. If it fails open, the readiator fans will not come on at low speed after the ignition is cut off, regardless of how hot the engine is after shutdown. If it fails closed, the fans will always run, and will kill the battery in a few hours.
I don't know what the exact switching temp is, but I would guess somewhere around 200 deg F.
The sensor that tells the ECU the incoming air temp is part of the Mass Air Flow sensor.
>When this sensor fails, will the fans stay off after the car is shut off despite a hot engine? I get this paranoia now that my connectors could be fried because when my car is hot and the fans are running, the fans shut off after I turn off the car instead of staying on.
>So I should be reading infinit ohms.... May I ask where, if it is still used, the intake air sensor is?
The inlet air temp sensor - or, perhaps we should say the intake manifold temp sensor - is a simple off-on thermal switch. If it fails open, the readiator fans will not come on at low speed after the ignition is cut off, regardless of how hot the engine is after shutdown. If it fails closed, the fans will always run, and will kill the battery in a few hours.
I don't know what the exact switching temp is, but I would guess somewhere around 200 deg F.
The sensor that tells the ECU the incoming air temp is part of the Mass Air Flow sensor.
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Originally Posted by Brett Rickman
...can be resurrected most times, but often fail at @ 100,000 miles. I'm at 101,258, ... I had sprayed WD-40 down the breather line, 4 other times, with no change in my problem.
If it was me I too would replace the RIA/ISV if I was in your shoes. I tend to spend money on new parts if old parts are suspect. However, I tend to have more money for parts than I have time for futzing twice with the same part.
As for my RIAs/ISVs with 55k, 80k, and 122k on the fleet, all are fully operational.
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Ok, got the intake and valve cover powder coated, new hoses and other stuff replaced, reassembled everything, and the car still won't idle for long....
THOUGHT I'd checked the readings of the idle position sensor, but going over everything, I guess I hadn't. Readings at the LH plug tell me the sensor is shot, one is on order. Guess I have to miss the Frenzy AGAIN for this year....DANGIT!!!!!
THOUGHT I'd checked the readings of the idle position sensor, but going over everything, I guess I hadn't. Readings at the LH plug tell me the sensor is shot, one is on order. Guess I have to miss the Frenzy AGAIN for this year....DANGIT!!!!!
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Brett-
What sensor is dead? The closed throttle switch? Are you sure it's not the MAF? Have you tried unplugging it to see if that's the culprit? Just a thought. If we diagnose the REAL problem, you might still be able to make it to the Frenzy.
What sensor is dead? The closed throttle switch? Are you sure it's not the MAF? Have you tried unplugging it to see if that's the culprit? Just a thought. If we diagnose the REAL problem, you might still be able to make it to the Frenzy.
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It's the "switch" on the throttle shaft, left side of the throttle body..... LH plug pins 2&5, 3&5, just off idle, and almost full pedal. 'Sposed to be <10 ohms at idle, infinite just off idle, 2&5, and infinite up until just before full pedal, when it goes to <10 ohms. Pages 03-20, and 03-21, of the WSM. And the readings I get, are nothing like those!
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Are you sure the throttle cable isn't holding the closed throttle switch open ? You should here a click from the switch if it is activating OK.
The WOT switch does not click
The WOT switch does not click
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Mornin' John,
Here is a part of my back-and-forth with Rich;
>When the fellow ( my helper ) just opened the throttle, the meter went to >116 ohms, and the book sez it should have gone infinite. Between 2&5. When >he operated the pedal when I was watching 3&5, as I said, it was at 58.5, >but as he opened the throttle, it went to 60.4, by 1/4 pedal, and never went >to infinite, or as the book said, <10 ohms.
> I think I can say the idle switch is shot!
And yes, I made sure the cable was not holding the switch open. The meter should have been reading <10 ohms there, but it was reading 0 ohms, and Rich said it should be reading 2-5 ohms at least?
Thanks for cross-checking! No-one seems to've had my symptoms before.....
Brett
Here is a part of my back-and-forth with Rich;
>When the fellow ( my helper ) just opened the throttle, the meter went to >116 ohms, and the book sez it should have gone infinite. Between 2&5. When >he operated the pedal when I was watching 3&5, as I said, it was at 58.5, >but as he opened the throttle, it went to 60.4, by 1/4 pedal, and never went >to infinite, or as the book said, <10 ohms.
> I think I can say the idle switch is shot!
And yes, I made sure the cable was not holding the switch open. The meter should have been reading <10 ohms there, but it was reading 0 ohms, and Rich said it should be reading 2-5 ohms at least?
Thanks for cross-checking! No-one seems to've had my symptoms before.....
Brett