ok guys, once again im stumped. i just recently put my car back together and the thermostat wasnt opening up. no problem, put another tstat in it and it still isnt opening, the lower radiator hose is cold. so i take the tstat out thinking maybe my water pump is screwed and the car cools fine. so i put yet another tstat in my car and same thing. the sensor that is attached to the tstat housing, one of my wires to that is disconnected. does that have to do with my tstat opening up??? it should have nothing to do with water temp other than to give a reading right??? someone please help

thanks in advance,
Carl

 

1. First clue is you say you put it back together.
2. Did you put it back together properly?
3. That means routing water/heater hoses correctly.
4. What you are describing is typical of when heater and bypass hoses are swapped by mistake.
5. You will want to fix your fan switch wires at the t stat housing.

 

could you give me a little more info on the heater and bypass hoses, where they come from and where they should connect??? its very possible that i may have messed that up. i just put the head on and connnect everything where it lines up at.

 

It is almost impossible to route the hoses wrong. What type of thermostat are you using?

 

170degree from discount auto parts, its brand new. thats what i figured about the hoses routing, everything usually falls into place

 

buy an allways open.. problem solved.. we are in fl!

 

yea that would work if vtec didnt require a certain temp to operate. i tried running no thermostat and the car wouldnt heat up enough for vtec to operate.

 

I speak from experience and know mistakes happen, and how easy it is to do it and still look right depends on your setup.

A guy posted here recently with the same problem and I advised him the same, as I have seen guys swap motors and make this mistake. He pmed me to let me know he did indeed cross the hoses, which is quite easy to do if you have the "U" shaped bypass hose, which to a lot of people appears to fit as it should between the two nipples on the thermo housing (see red illustration).

Looks right when hooked up, but isn't. Here are drawings showing how easily it can be messed up, with all three nipples being so close together on the engine and all three hose ends reaching these nipples in any combination and still look like they were meant to be routed that way.

The green shows correct, the red shows one possible combo of a wrong hookup that would lead to the thermo not seeing enough hot water from the head to open, at least not without a lot of running and residual heat build up eventully heat soaking everything. Trouble with that is you can actually overheat the top end of the motor and blow the rad cap with an ice cold bottom radiator hose, really making you wonder what the heck is going on.

Obviously you may have another problem. Just trying to help, and offering one possibility that does and has caused the symptoms you have described.

 

thanks for the good diagrams, ill check when i get home. i apprecaite the good info. reps given for sure!

 

now that is good stuff! yeah, come to think of it, boostedcoupe, does the temp go down if you turn your heater knob to hot? does it go down when you have the heater on?