97 2.3 heat fluctuations
 

Ok i have been reading through all the threads on this matter and still am stumped. As said in my sig, i have a 97 ranger 2.3l 5-speed no A/C No P/S. until last night the truck would not warm up at all so last night i pulled the t-stat and checked it and it was fine. Now to the main point. I believe that the t-stat was not seated properly because this morning while driving my gf to work the truck warmed up pretty quick but when i stopped at a light, stop sign, or parking lot, it went right back down to below c. I am thinking its the heater core but i want to make sure before i go throwing parts and money at it.

Re: 97 2.3 heat fluctuations
 

I would start by replacing the t-stat with the highest temp Motorcraft t-stat you can get. 190 degrees? {#F8CZ8575AA}?...........They need to be seated properly.......then makes sure you get all the air out and that it is topped off with coolant....These engines run kind of cool as it is...the heater core is only about $50......but ford allocates about 8 hours to do the job...the first thing you need to do is get the engine heating up properly..........Fireranger has a troubleshooting guide that is great....... http://www.fordrangerforum.com/how-s...ing-guide.html

Re: 97 2.3 heat fluctuations
 

i have a 195in it right now and it does heat up while im driving but if i stop it goes down to cold again

Do you know if you have both temp sensors next to each other on top of the tstat housing? If you increase the rpm while idling does the gauge go up?

______________________________
sent from DROID Bionic using tapatalk-2. (Ranger, 1999, reg cab, 2.5, 5 speed, 2WD) (2006, Vibe, 1ZZ, Auto, AWD)

Re: 97 2.3 heat fluctuations
 

yes both temp sensors are next to each other but they are not on top of the t-stat housing. there are connected to the heater hose coming off he t-stat and no it only increases temp when i drive down the road. once i stop it drops to cold no matter how i rev the engine

http://www.fordrangerforum.com/membe...mp-sensors.jpg

Re: 97 2.3 heat fluctuations
 

ok got an update. Just went to pick my gf up from work and while sitting in the parking lot waiting for her i revved the engine and closely watched the gauge and while revving it went from cold to about 1/3 way u.

Do a pressure test on your cooling system. Seems like its not holding pressure. I could be wrong but worth a shot. Your 100% sure the t-stat is good?

--Official "Dj is a whore" signature (brought to you by my pos phone so I can troll dj on the go!)--

Re: 97 2.3 heat fluctuations
 

yes pulled it out was (closed when i pulled it out) and put it in a pot of water. How would i go about doing a pressure test? I have never done one.

Re: 97 2.3 heat fluctuations
 

Well if you are sure the radiator is full of coolant then this points to a bad water pump

Please help me understand. A bad waterpump would keep the engine from actually heating up?

______________________________
sent from DROID Bionic using tapatalk-2. (Ranger, 1999, reg cab, 2.5, 5 speed, 2WD) (2006, Vibe, 1ZZ, Auto, AWD)

Re: 97 2.3 heat fluctuations
 

Ok.....I will tell you what i know about these engines.......from what I can gather.....they run cold....I have heard a few people say that because they are small 4 cyl and that they are iron......they take longer to heat up..not sure if that is true. I also heard people say that if they had electric fans they would warm up better....I am not sure if that is true either because my t-stat is just not opening up when it is cold outside........I can attest that if I drive my truck for 30 minutes or so the engine does get hot enough where I can idle and have heat.....

as far as I know the best you can do is

1) put a motocraft t-stat in there......the MC sits propery and has the proper bleeding hole......some of the other do not sit right and do not have a bleeder........these can keep air in the system and allow coolant to bypass the t-stat ............

2) Make sure it is topped off. I noticed a few years back when I got the truck that my dash temp gauge would be at C after the truck was warmed up and if I revved the engine for about 2 seconds the needle would go up into the normal range. I changed my t-stst and in looking at the system I realized that my coolant had been a little low and that my sensors were not submerged in any coolant........when I revved the engine I am thinking that the waterpump pushed coolant over them and thus the gauge went up......when I stopped revving, the gauge would go down.......I filled the system to the top and got the air out.....it never did not again........You also want to make sure you have a good radiator cap on it......

3) keep the system clean from rust and debris.........

I have a torque pro.......so i can watch my coolant temp now. this morning it was about 15F outside.....I started the truck and let it warm up for 15 minutes..I then drove about 2 miles and let it idle for a while........the hottest I could get the temp was 150F.......I picked up another new stant rad cap but I don;t think it will help......thoughts?

Re: 97 2.3 heat fluctuations
 

You are looking at this wrong, a diminish ability of a water pump (think vanes corroding away) will not pump water and the first thing that low water or poor performance of the pump affects is the heater core. You say your t-stat is OK and you do get heat sometime so that rules out blocked core. Water pump is something that will go bad in every vehicle if kept long enough and is a maintenance thing to do. Your call

Re: 97 2.3 heat fluctuations
 

On my truck and I think the Op's(obviously not sure) my issue is getting the engine to warm up.....my heat is consistent...when the engine temp is below the "normal" and near the C the heat is warm(coolant temp about 150F).....once I get the engine to warm up the heat works great....The issue I have is getting my engine to warm up.....it takes along time. i.e. If it is 15F outside and I start my truck and let it idle for 45 minutes the temp will not go above 150F .....and as far as I can tell.......my tstat is working and I do not have any coolant bypassing the tstat......the upper hose is cold for a while..

Re: 97 2.3 heat fluctuations
 

@ddunfee Thats what I was thinking that my water pump was going bad. Saw somewhere else that the fins can rot off and not provide adequate flow. @modelageek I had the same problem for a bit, I just took a piece of sheet metal and made a cutout to match the shape of the grill to block some of the airflow through the radiator. Now it heats up just loses all heat when i stop going which leads me to what ddunfee was saying about the water pump. Gonna check it out in a while. Thanks for all the advice and input. Much Appreciated.

Re: 97 2.3 heat fluctuations
 

I agree about blocking the radiator..that does help....staples sells a perfect size poster board for $5 that fits over the rad. I use a bungy cord........that being said........I am and have been for a few years now perplexed as to why I can not get the truck to warm up sooner in the cold........was it like this when it was new?...was this the design?