I am third gen dumb. 4th Gen is my specailty so I was hoping you guys could help me out. I got this car with no working motor, so I swaped in a working 305. I've got everything running, or so I thought. The guy that had it before me told me that the temperature gauge and the oil pressure gauge didn't work. Well I've got the op gauge working but the temp gauge doesn't work yet. The fans don't come on either. I've replaced the sensors in the therm housing and the sensor in the driver side head. The temp gauge constantly shows pegged to the high side. Anybody have an idea how I can fix the gauge and the fans?

 

well the guage sendor is in the drivers side head.

a good ones should peg the temp guage and then go back down to zero when u start the car.

u sure u got the guage sendor? for the head? should be a one wire connector.


as for the fans thats a different story, the drivers side comes on by the computer and that reads the temp from the coolant temp sensor in front of the engine.

the passengers fan works off a/c pressure or the fanswitch.

i would really look at the fuse in the fuseblock to make sure its not blown, then next test each fan by hooking it up directly to the battery just to see if it works.

after that u need to do some relay testing.

 

Yep I got the proper sensor for the head. Also I didn't mean to say "fans", this thing only has one fan. I've been reading a bunch of other posts on this board about this problem and after making sure the fan actually works, it looks like the next best bet is to look at the fan switch. Where exactly is the fan switch located? As for the temp gauge, is it possible that the gauge itself could be bad?

 

yeah i do think that the temp guage "can" go bad, i know they aren't the most accuarate to begin with but havent had to deal with a bad guage all together.

maybe see if a place like auto zone can at least scan your computer to see what temp its reading if any?

fan switch is located between the 6 and 8 cylinders. passengers side.

 

Well I've looked on the passenger side head between 6 & 8 and all I see is something that looks like a plug. I can't even get the friggin thing out. Is this the fan switch? If so what plugs into it? Can someone show me what this fan switch looks like? Also as for the gauge. I took it out and it looks as if the needle was stuck on the edge. I read on here where someone glued something in so that this can't happen anymore. Also when I moved the needles on other gauges they seemed to spring back to their previous position whereas the temp guage stays where I put it. Is this a bad sign for the temp gauge?
I just want to thank you for all of your help so far. Hopefully we'll get this thing figured out soon.

 

The cooling fan switch is located passenger side cylinder head by the a/c evap housing(A PAIN TO GET TO). the plug is round one wire same as Knock sensor plug. you must pinch and pull the plug(There is a good chance it will break but you can find replacement plugs).You can test buy touching with test light ign on see if fan comes on.

 

This might be a stupid question but I'll never know the answer unless I ask it. I was told by the guy at the dealership parts counter that if the car had a temp gauge and not just a light then the sensor inbetween 1 and 3 should be two prongs. That would explain an extra wire I have in that area and why the plug I'm using has so much slack in the wiring. Also if this is true can I use the sensor that only has a single plug as the fan switch. I haven't actually ever seen this fan switch but from what I read it just completes a ground when the engine temp gets high enough. I could be waaaaaaay off base but this is just an idea that came into my head. This is hopefully the last major challenge that I'm going to have with this car.

 

lil help.

 

guage sendor in drivers side head is a one wire connection.

fan switch in passengers head is a one wire connection.

yes the fan switch grounds out at the certain high temp which is grounding that relay and turns the passengers side fan on.

 

fan switch

 

guage sendor

 

well after removing the temp gauge and then putting it back into the gauge cluster it works again. Now just need to tackle the fan. Of course I was a dumb butt and didn't let the car warm up enough to run the fans but that is what tomorrow's for anyways right. Figured I should quit while I'm ahead. I'll let you all know about the fan switch tomorrow, hopefully there is more good news to be had.

 

In a single fan setup, there is no switch in the passenger side head. That switch would be for the secondary fan. (which, you dont have.......)

 

yes there is, in a single fan set-up, it controls the primary(read=only) fan, along w/a/c on trigger from ECM(or a/c pressure transducer, depending on year)

 

Hey MdFormula350!
Nice Headers... Where you got them???

 

i replied to ur pm, this thread is old!

they look nice new after some use get use to brownish colors

check my cardomain website for more info.