1996 ranger stuck on a/c no heat

[puke]

2.3, 5 speed, 2wd.
Heater isn't worth a crap, a/c is awesome.
I disconnected the heater core and blew it out 2 or 3 times with compressed air and clean water (with cleaning solution) until it was clean.
Still very little heat (have to have the fan on the lowest setting to even tell...maybe when going up a hill I can have the fan on #2 and it stays warm.)
I checked the temperature of this inlet and outlet hoses (to the heater core) and there was only about 3 degrees different,.. but they were not exactly the same.. I think they were around 180 degrees according to my cheapo infrared thermometer.
At this point, I assumed it was the blend door,..so I cut a hole in the plenum to check ,.. The blend door seems to be functioning properly.... At least..if I understand what I think it is supposed to be doing. In "heat" mode,..it is parallel, or inline..with the truck.. in cool mode...it goes clockwise out of sight...so I would need a mirror to check where it stops. But when I switch it back to heat mode, it always comes back to parallel with the truck


Anybody have any ideas????...oh, by the way,, I've replaced the thermostat a couple times with my fingers crossed hoping, but no luck. Since the heater works best going up a steep hilll,... I think I will put some cardboard in front of the radiator during the winter...can't hurt. I have to do that with my diesel truck or it never really get's warm enough.,

I am at a complete loss here. Don't know where to go next. is it somehow sending the heated air outside someplace??? Where could it be going.? I mean, I turn the fan on high...and the air coming out isn't much warmer than outside air (completely worthless as a heater in that respect)..but if I keep it on low..at least it is warm air coming out.

Please chime in with any ideas.

 

[Big Jim M]

Here is what I'd do. Now that I have a hole to look at the blend door is good. I would get her up to temp so the thermostat is open. Then I'd take the EWXIT hose off of the heater. Then I'd start her up again and see how much coolant comes out of the open hose. If a great deal then I know for sure the blend door is the cause. If only a small amount then I know the heater core is blocked.
If the blend door then I can open the hole again and turn the heater on to see what air comes out of the now open hole.
I think that door is controlled by vac, but I may be wrong. If vac controlled then I'd do a complete check on all hoses and the canister.
Big Jim

 

[ssny1088]

heater

I believe the 96 is the same as 97 so this may help. It sounds like you've done the blend door check right, though it never hurts to double check, as they are known problems. (I speak from experience) Before condemning heater core, there is a valve(should be) on heater lines. Do go bad or lose vac. You could disconnect the two lines going to core and put garden hose to input side to see flow.If good, problem is elsewhere. If clogged, you could try backflushing (hook hose to return) If that fails, try getting all water out of core(shopvac) and fill core w/clr, radclean or muratic acid(watch paint) tie/put both hoses above core height and let set for 1-2 hours and try backflushing again. This sometimes works, depending how bad. May save you from pulling core.

 

[ssny1088]

another thought

I have a 97 2.3 5 speed 2wd, so basically same truck. If all the above fails, and I'm not sure this could be your problem as you stated you have good airflow but cold,but mine had a mouse nest behind blower motor. Don't know how it got in???? Also could check for holes or cracks in under hood ductwork.

 

[puke]

As I said, I did cut a hole in the plenum and the air door seems to be working properly with zero malfunction.

If I understand correctly,..a mouse nest would deter the flow of air,...which doesn't seem to be having a problem.

As I said, the core was flushed a couple of times right after I got the truck and it made little or no difference.

With that little valve that is run on vacuum....(I can't even understand why it exists..since the air door in the plenum seems to be the thing that is supposed to regulate temerature.).. I don't read where that valve is ever a problem,..but,,...I am wondering if the lines from the valve to the engine/rad. ever get clogged up with gunk..I haven't read where that has ever been the problem,...but..I suppose maybe it could happen. Maybe I'll try to back blow them both.

 

[ssny1088]

puke

If you pull the blower motor out (easy job) you can see in to core(and any junk) While out, get truck to running temp and feel core. Hoses can still get hot w/clogged core(and so can core, until you turn on blower) That inline valve on hoses let,s motor warm faster by shutting off flow to core. Also shuts off W/ ac on or heater off. Can stick or clog.

 

[puke]

If you pull the blower motor out (easy job) you can see in to core(and any junk) While out, get truck to running temp and feel core. Hoses can still get hot w/clogged core(and so can core, until you turn on blower) That inline valve on hoses let,s motor warm faster by shutting off flow to core. Also shuts off W/ ac on or heater off. Can stick or clog.

OK, pulling motor seems logical and easy.
One more thing. Since this ranger is 19 years old,..could it be that someone has mixed up the inlet and outlet (to core) hoses.???? They are side by side (rather than over and under) leading into the cab...so I am not certain which one is SUPPOSED to be the inlet,..even though I probably should check that out in case it was switched at some point. I think this was a california san diego truck for the first 8 or 10 years of it's life....so heat wasn't an issue. And the guy I bought it from (was "given to him" by his califonia brother in law) said that the heater had NEVER worked right since he had it.

By the way, if that valve is just to help the truck warm up sooner... I am thinking what is really is..is something extra to go wrong. I could swear they didn't have anything like that when I was younger.

 

[puke]

OK,
I have a question,... (elephant in the room type question).
As I said,..if I'm going up a hill or grade...the heater works much better.
I pulled the grille and put cardboard over the whole thing.
Now it's a bit better.....about as good as if I was going up a hill.
My question is.
COULD I HAVE GOTTEN 2 BAD THERMOSTATS IN A ROW??????beside the original????
The temp guage never get's above the C,..except in summer on really hot days... (just a little above). SO, with the cardboard installed blocking the whole damn radiator...the needle gets to the top of the c,...but I don't know until I get on the freeway...if will actually get warm enough for the needle to no longer touch the C... Most of my nissans and hondas...then needle was like 1/3 from the C,...would never get to half...but always got wayyyy abovfe the C. But I have read in this forum and others..that the temp guage on these is a bit of a joke...so I take the temp needle with a grain of salt... Where should the temp guage be sitting when it is warmed up?????????? (if you have a ranger mid 90s??? I mean,...I would think that I should not be able to comfortable touch the radiator hoses...but I can. After I put in this cardboard..I can still comfortably touch them...but if the hoses were any warmer I would think that I would say we were moving into the uncomfortable zone.

 

[Big Jim M]

You wrote: I think they were around 180 degrees according to my cheapo infrared thermometer.
If true then the thermostat is working as designed.
So you have heat going in and coming OUT the core. That can only mean the BLEND DOOR isn't working.
Big Jim

 

[puke]

You wrote: I think they were around 180 degrees according to my cheapo infrared thermometer.
If true then the thermostat is working as designed.
So you have heat going in and coming OUT the core. That can only mean the BLEND DOOR isn't working.
Big Jim

I better dig out that thermometer..and check it on another car. Maybe it's readings are way off. Since I cut a hole in the plenum to see the blend door working, that is not the problem.

 

[puke]

OK,
The heater (actually a/c) outlets read 91 degrees with the fan on 2 and with cardboard COMPLETELY over the radiator (had to take the grille off to do this). The temperature goes down quickly iff I turn the fan on faster settings.
The ranger motor reads 140 degrees.
The water temp inlet to the core floats 120 to 130ish (fluctuates a lot..not sure why),..the outlet is about 5 less.
I don't know how it "came" with a new bad thermostat,...and I replaced it twice and still is crap?????? I did read on the forum that you are asking for trouble without oem and I am sure the ones I got were from autozone..whatever they gave me (I doubt they would give the oem if they could make more money on their aftermarket one). That would explain why the heater is much better going up a hill.

I am going straight to amazon and ordering an oem,..and I think there is a gasket thing...(if I recall...it has been about 3 years since I've really monkeyed with the heat in this thing.). Not sure what the gasket thing is...but I could swear there was something there besides just the thermostat...my age is showing when it comes to memory.

 

[enjr44]

I am guessing that the AZ thermostats are not the constructed the same as the OEM ones. I just replaced mine on the 08 and the Motorcarft was physically different than the ones offered by O'Reily's. And three times the price.

On a Ford temp gauge the needle should go up to just below the middle of the gauge at 195 (I think, IIRC, halfway is 210). My symptoms were low heat, gauge and heat would go up on a long uphill and down going down a long hill; but, never reach the 190 spot. The OEM stat fixed it.

 

[Big Jim M]

You are correct. 120-130 isn't hot enough. So what I surmise is the thermostat has failed on the OPEN position. That is much better then the closed position!
The major difference in thermostats is the HOLE that Ford puts in their thermostats. The hole goes at the highest point when installing the thermostat.
Big Jim

 

[ssny1088]

thermostat

In your first post, you stated the hoses got to 180, no mention the temp didn't go up, which made it quite confusing. Anyway,most 2.3 stats look to have a rubber seal on them. Never having changed mine,not sure the purpose but on a 2.5 GM I had, the neck was corroded so the stat seal (not the neck gasket) slipped and allowed coolant to flow around thermostat, never allowing motor to fully warm-up.Guess I'm asking a question of other members as much as throwing a idea around. Two bad stats in a row would be a long shot. Installed wrong?

 

[jeremysdad]

You are correct. 120-130 isn't hot enough. So what I surmise is the thermostat has failed on the OPEN position. That is much better then the closed position!
The major difference in thermostats is the HOLE that Ford puts in their thermostats. The hole goes at the highest point when installing the thermostat.
Big Jim

I bought a Stant 195* at Advance Auto and it has the bleed hole, as well.