Hey everyone! I’ve got a 2006 Ranger Sport 3.0L with 110K miles. I’ve been having some trouble with it lately and I’m not sure what to try next. I took it to a shop and they told me the head gasket WASNT blown. I’m unsure of this. Let me tell y’all what’s been going on. First I was on the highway and I had a bit of an engine shake, I decided to do a tune up. I replaced the ignition coil, wires and all 6 spark plugs. I drained the coolant and refilled that also. Changed my oil and filter. Replaced the bank 2 o2 sensor. Changed the fuel filter also. Truck has been running fine but it recently threw a few codes. Upon inspection of the codes I replaced my engine thermostat, when I took off the old thermostat it’s actually missing the spring! Where did it go? Heater core possibly?? I can get the truck to start just fine, but not more than a day. It will blow the cap off the coolant reservoir, it will not blow any hot air, engine will overheat. I’m really hoping this isn’t a head gasket issue, I do have a new head gasket kit and head bolts just sitting in the back but I don’t have the know how or the help to do this job. Could this possibly be my broken thermostat plugging up the heater core causing my issues? Anyone around the Irving area in TX to help a guy out? Any tips or tricks? I’ve got the Haynes manual, lol. I’ve never worked on a vehicle before besides this little ranger and I’m having a blast learning and doing the work myself but I know the heads is beyond my skill set most likely tho I believe I could do it with another set of eyes/hands. Let me know if y’all think this is the head gasket or if I should check the heater core for a blockage, or if my thermostat could be anywhere else.

Cylinder 6 spark plug - got a code for cyl 6 misfire no wonder

All 6 bad plugs, I’ve replaced with new ones

 

Blown head gasket or cracked head or both. You can do the rubber glove test on radiator. Search Google. You can do a compression test on engine too.

 

Welcome to the forum

Thermostat spring goes inside towards engine, and no sping can't go anywhere or block anything, should just be down in the coolant passage in the intake, not a big deal at all
Make sure you put the new one in the right way, spring down, had to say this, not trying to be insulting
(like on a No start issue, have to ask if there is gas in the tank, first, lol)

Heater will not blow hot if coolant gets low, heater is at a high point

Simple test for blown head gasket
Cold engine
Remove rad cap
top up radiator with water or coolant your choice
Start engine
Watch rad cap opening
Might get a burp of water out but then it should stay level inside rad, no water should come out, if it starts to over flow after 1 or 2 min of idling, or sooner, then you do have a blown head gasket or cracked head, period, not a guess

I would do the test first before looking at other things
Because cold heater, and overflowing reservoir means overheated engine because of low coolant, and unless there is a big puddle on the ground under the truck, it has to be going somewhere

Blown head gasket is a double whammy because it uses coolant but it also injects "air" into the cooling system, which displaces coolant in upper engine so heater goes cold and engine starts to overheat, the coolant is displaced into the overflow reservoir
So you have the symptoms, lets see if you can find the cause

 

Haha, I definitely have gas in the tank. Half a tank the last I checked.

When I replaced the thermostat and noticed the old one had busted I did reach inside the intake passage to try to find the spring, no dice. Have no clue where it went. It’s blowing my mind not knowing where the heck it went. A mechanic told me it’s in my heads or in the heater core. Causing me to not get hot air.

The rad and res are full of coolant I made sure when I did the flush. I actually did this twice, still not blowing hot air, only cold even with the engine warm. Never had issues with the heating before these symptoms popped up. I put 3.5 full jugs in the rad/res.

I forgot to mention when mechanic did tell me my head was blown I tried some head gasket sealant. I followed the directions to a T. Wondering if this has made my issues worse, if I should do an engine flush?

the truck was not running hot till recently the last time I drove it. I got home and popped the hood and noticed the cap on the coolant res was blown off and coolant had sprayed all over under the hood. Never had a puddle of coolant under the pickup. And now the coolant level in the rad looks low.

I will try the glove test but it’s sounding like I’ve unfortunately blown the gasket.

I feel like it’s worth the time replacing, I think I can get more than 110K out of the engine after I replace the gasket.

 

I thought you said mechanic said head gasket was not blown?
My mistake

Cold engine
remove either heater hose at the firewall
Remove rad cap
top up rad until water comes out heater core fitting and open hose end, this clears all the air out of the engine side of thermostat, and heater hoses, put hose back on

Head gasket issue pumps "air" into the cooling system, and the heater hoses is where that air goes first, so no heat