temp sensor questions

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Nov 14, 2005 | 10:10 AM

TJshan68

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From: rushville, NY

temp sensor questions

I just bought a 1988 Honey Motorhome on a E250 chassis, 351 Fuel Injected auto (I believe it is a Cleveland).

The temp guage was not working which I tracked down to the temp sensor on the intake manifold, and will get a new one in there today. Anyway, I believe the engine is running rich, and the FI is staying in choke mode, she seems lethargic and the exhaust smells rich. With the temp guage working soon I will be able to see what temp the engine gets to and determine if the thermostate is working properly, but I believe it is from the feel of the engine temp.

Here is the question. Does the computer get its temp reading from the temp guage sensor? if not where from? If it is running rich, what else could be the problem? Is there any way to "test" other then looking at the plugs?

Thanks for all your thoughts.

Tom

Nov 14, 2005 | 12:16 PM

beartracks

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From: Albuquerque

You probably had a Winsor engine. I would think you would have a seperate sensor for the computor (not sure). It should set a check engine light if the computer cannot read the water temp.

Nov 14, 2005 | 05:50 PM

TJshan68

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From: rushville, NY

Well, got the temp sensor in (yes, it may be a Windsor according to the parts counter guy) and now have a temp reading (1/3 on guage when warm) but it still seems to run rich, also, does not seem to kick down to idle... make me wonder more about another temp sensorfor the computer.

There is no tach on this van either, does anyone know where to pick up a tach lead?

Nov 15, 2005 | 10:20 AM

beartracks

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From: Albuquerque

i'd start looking for and checking all the sensors for temp. Coolant, intake air. I don't know if you have any others. They are all basically a resistor that varies with temp. so you can check them with a multimeter. If one doesn't function the computer will think the engine is very cold and add a lot of fuel.
Another possibility is a stuck injector.

Nov 15, 2005 | 11:21 AM

Torque1st

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Moved to Windsor forum.

Nov 17, 2005 | 09:43 AM

TJshan68

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From: rushville, NY

Can not seem to locate the other temp sensor, its not on the forward part of the intake or the Rad or rad hoses, anyone know where it would be?

I was able to remove the two rearmost spark plugs (eisiest to get at) they look OK, but one had some slight electrode insulatong worn off. I believe that means pre detonation right? What would cause that?

Nov 17, 2005 | 10:44 AM

Kemicalburns

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From: Bend,OR

check codes. www.fordfuelinjection.com has instructions on this using a paperclip.

there are many sensors that will contribute to a rich condition. its possible that your thermostate is either stuck open or there isnt one in there