have a 89 ranger with 4cyl.engine light flashes randomly while driving.and it doesn't get very warm.sometimes it will almost get in the normal zone but never warmer.do these two have something to do with each other?and is there a sensor or sdomething to do with temprature?or is it just the thermostat?thanks for any help

 

I'm guessing the thermostat. That's atleast where I would start since it is relatively cheap and easy to do.

 

I agree, it sounds like a thermostat problem.
How is the heaters output on a cold morning???? If the air is just warm, not HOT, then it's likely a stuck open thermostat.

The blinking trouble light could be a misfire sign, why not run this puppy by your favorite autoparts store for a no cost computer trouble code scan, then post ALL the code numbers found, here.

If the engine isn't fully warming up, thecomputer has likely set a closed loop code, as it doesn't like running cold.
Your mpg will suffer too, as the computer will keep the air/fuel mixture richr than if it were warming up normally.

Let us know what code numbers are found.

 

thanks.i will try and stop by a auto zone this week.and let you guys know the codes.

 

changed the thermostat last night.and now it doesn't even get as warm as it did before.won't even move off of the cold mark.and heater doesn't get all that warm also.think it could be the radiator cap?just throwing some ideas out there.

 

With the temp gauge not moving & the heater not putting out, sounds like your new thermostat may be a bummer!!!!

It happens, just because it's new doesn't automatically make it good. I've seen plenty of bad parts, right out of the box!!!!

 

thanks pawpaw.guess i will take it out and test it.or maybe just take it back.

 

You may find it stuck open, when you remove it.

 

just pulled it out.was closed

 

seems to be working fine.when i do the boiling water test.

 

OK, good idea to check the thermostat.

Well did you ever actually touch the engines radiator hoses, after the engine had time to fully warm up, to see if they were hot????? If the engine is fully warming up, the hoses should be uncomfortable to touch.

If it seems to be warming up judged by the touch test, then you likely have two separate problems.

One would seem to be with the dash temp gauge not registering, so remove the single wire temp sending units electrical connector & ground it briefly, while you check the temp gauge. It should read Full Scale Hot, if the wiring & gauge are ok.

If not, suspect the gauge temp sending unit.

On the heater not putting out, if the engine is determined to be heating up fully & your not getting any, or much heat out of the heater, then check the heater core for restrictions, or if flow through the core is ok, because both heater hoses are hot, when the engine is fully wrmed up, then you likely have some kind of control problem with the blend door.

If you come to think this may be your problem, check the "Tech Info" thread, atop this forum & scroll down to "blend door fix".

If all that checks out & the engines radiator hoses are not Hot to the touch, then something is wrong with the thermostat, or it was installed wrong maybe.
If the engine really isn't warmng up, then the thermostat isn't doing it's thing & properly controlling coolant flow.

Which brand & temp range thermostat are you using????


BTW, what computer trouble codes has AZ found????

Just a bunch more thoughts to ponder.

 

haven't made it to az yet.put a stant 195deg thermostat in it.will check the hoses.but don't think they are getting warm.copper part of the thermostat goes toward the block rite?

 

drove it to the store and back.long enough every other vehicle i own will warm up.and when i got back you could hold on to the hoses as long as you wanted to.heater hoses were warmer than the one from the water neck.thanks pawpaw

 

does this motor have anything else that controls the temp of it?

 

Just the thermostat regulates the engines water temp by regulating flow through the radator.

So if it's acting out & opening too soon, or sticking open, or is mis-marked at the factory & is the wrong temp range, will it over cool the engine.

The thermostats bridge faces out, towards the radiator, the part with the big spring that you can see, goes toward the engine.