Need help bringing 1995 4Runner back to life.

So it starts….. but goods and bad. It was running super super low idle like 400-500rpms. I adjusted the timing to like 10ish degrees to the left of top dead center which helped with the idle rpms. I then took it for a drive and it would stall out when I came to a stop and put it into neutral unless I pushed the clutch in before I came to the stop. The rpms would drop super super super low and then stall but it would start right up with no issue when I went to start the car again. The radio didn’t go out so I don’t think it’s an electrical issue but open to anything. Thank you for any and all advice

https://youtu.be/1k1YI9SZsbc?si=WoN5ynpJcAz1ThK_

https://youtube.com/shorts/JC6RpfMyJXc?si=m7evDyp7bj1Lhsjf

https://youtu.be/qDthSWv0ZW8?si=i42wpOOIKj3xAzf6

 

Update.

So the low idle I think I fixed with some cleaning and adjusting. Not 100% but now dealing with a new issue. I had a bit of overheating while doing the big test drive. It was only over heating slightly and only when driving slow or stopped. While driving 40MPH+ or the heat on it didn’t seem to overheat at all. When I got back from the 3-4mile drive I parked and coolant began coming out of the overflow radiator tank. I refilled the radiator and let it idle. It didn’t overheat according to the gauge but it began to boil vigorously through the funnel.

Thinking it might be a clogged radiator I drained out the coolant and flushed of the radiator with blue devil radiator flush followed by flushing the system again with water for 10-15 mins. When I filled it up again with coolant it began to boil out the no spill funnel. *see video below.

I did an exhaust gas tester on the coolant and didn’t get any exhaust gases in the antifreeze so I don’t think I have a head gasket leak especially since I just replaced the head gasket. When I pulled the engine I did a good clean of the outside of the radiator also.

My guess is the radiator is toast but would like to hear anyone else’s thoughts before I drop another hundred on the 4runner.


https://youtube.com/shorts/QaZnOi8G2oo?si=8-aOosmW9gSoPkb2

 

The low idle and overheating could also be due to a plugged exhaust, like a rodent nest.

 

I’m so close. I replaced the alternator yesterday without taking the battery off. I hit the alternator power wire the the frame/ground which a little shock and blew the alternator fuse. I replaced the fuse and put every back together the correct way. Now I am getting completely no power in the vehicle. I checked the battery (new battery and fully charged, connections correct and tight) I checked the starter and EFI fuse both are between 80-200.

My question is what should I check next. I have no power anyways to the dash, horn or any inside/outside lights

 

Isnt there a 140 amp fuse?

 

Here is a picture of all the fuses I could find in the engine bay

 

Do you have continuity between the positive battery terminal and fuse box? There’s a fusible link built into the battery cable/ fuse box that might have blown.
https://www.yotatech.com/forums/f116/fusable-link-replacement-228307/

 

Check the fuse block under the dash on the driver side.

 

Is there a fuse on battery cable?

 

No. So I figured it out. I took a volt meter and started from the battery touched the positive and negative posts and was going to work towards different parts of the engine. Long story short the metal holders clamps that hold the battery posts were super greasy not connecting well. I cleaned them really well and it started right up. I feel pretty stupid but new to this

 

So last issue…the 4 runner continues to overheat. While driving the short distances and the air is flowing through the radiator the coolant stays within normal ranges just below the half way mark.

After coming home and letting it sit in idle the temperature slowly creeps up beyond the halfway point to the point where I shut it off before damage happens. I have done multiple significant flushes of the coolant system including 2 different coolant flush kits. I have replaced the radiator with a 3 row aluminum radiator. I pulled the thermostat and tested it in a pot of hot water making sure the thermostat opened and stayed open at 180. By the way it was a new thermostat when I replaced the heads. The coolant is actively circulating which helps me rule out the water pump which I also replaced when I did the heads. The current fan is working, not electric and is the stock pulley option. As a Hail Mary I put a bottle of water wetter in which didn’t change anything. No engine lights have popped up while driving the last few days that I have driven the 4runner.

I have hit a wall and am looking for direction, advice, ideas on what I can do to diagnose/fix the issue. Thank you all for the help.

 

A restricted exhaust might be the problem, not sure if you saw my previous post.
Exhaust might be coming out, but if it's restricted by a partially plugged pipe, cat, muffler, the engine will overheat. Exhaust gas is hot and not being able to evacuate properly causes the engine to get hot.
Bang on that thing with a hammer while running and see if anything comes out.

 

Deathbysnusnu!!! Thank you thank you thank you. I didn’t see your last post. I went out and banged the crap out of the exhaust pipe and nothing happened but it got me going down a rabbit hole for the past 4 hours about exhaust and I 100% believe you are right that it’s the engine exhaust that is being restricted causing it to overheat. I did a bunch of research the past few hours and some of the similar symptoms of a clogged/restricted exhaust such as lack of power and poor idle and this kinda puffing sound from the tailpipe from the exhaust all sound like symptoms people say are from like you said the exhaust not being able to escape.

I took the 4runner for a quick drive and was able to recreate the overheating issue when I got home.

I unfortunately don’t have any fancy tools to measure flow of the exhaust or even temp but I saw one video where someone took the upstream o2 sensor off just to see if they had more power which would confirm the a clog downstream at the converter or muffler. I tried but unfortunately the exhaust bolts on the upstream o2 sensor are completely rusted out that I couldn’t get them off. Future project for another day. Anyways I undid the 3 nuts connecting the exhaust pipe to exhaust manifold and pulled the pipe down just enough it would let the exhaust out.

I started it up again and within 2-3 minutes the coolant temp went down to within normal range. I took it the 4 runner out for another 2-3 miles drive pushing the 4runner to 60+ mph and no issue at all with overheating. The 4runner sounds like a big semi truck due to the exhaust not passing the muffler but no overheating!!

So…. I think you’re right? My plan now is to look into finding out where the clog is. Im thinking either the catalytic converter or the muffler or like you said hopefully just a mouse nest blocking a bend in the pipe.

If it is the catalytic converter that’s clogged I have read some about using a catalytic converter cleaner additive to break up the carbon deposits in the exhaust. I would like to know if you have had any experience or heard anything about these products. I think longer term being just a complete replacement of the catalytic converter but $30 today fix vs $100-200 next week fix with welding, shipping etc.

 

I have no experience with cat cleaners, I'd either replace the cat or if you are in a state that doesn't do emissions, I'd cut it out and install a straight pipe. It's old enough most states would give it a pass.
Shove a fish tape or something flexible and retrieve-able up that tailpipe and see if any nest material comes out before throwing any money at it.