Overheated due to leaking radiator, getting misfires after installing new radiator

Last weekend my wife was driving the 4runner and it died going down the Interstate. Had it towed back to the house. She said there were no warning signs until it actually died and the dash lit up. Truck has had the P1135 error forever so the check engine light is always on.

Anyway, I started it up and drove it into my shop to work on it. I left a trail of transmission fluid. Turns out the transmission coolant line had separated at the radiator (the whole nibble had come off).

I removed the old radiator and was very surprised that it was dry as a bone (no coolant). This was not a good sign. I inspected the radiator after removal and found what looked to be a leak. See below pic.



Got the replacement Denso radiator and completed the install this morning. It took a little over 1 gallon on transmission fluid and about 2.5 gallons of coolant (pink stuff from Toyota).

While I had the truck in the shop anyway, I decided to do additional work. I did an oil change, cleaned the MAF sensor (removed and sprayed with CRC MAF cleaner as per the faq here), and also removed the TB and cleaned it. It was nasty:



The source of the oil seemed to be from the large vacuum line that runs to the top back center of the engine:



So I got everything cleaned up and put back together (re-using the metal gasket between the plenum and TB).

Starts up like before when I pulled it into the shop. That is, running pretty rough. I check codes with Torque and still only show P1135 (Air/Fuel sensor heater circuit response Bank 1, Sensor 1).

While it idles, I run it through the gears and then check the trans fluid level, it is at the cold mark which is good. Also check for leaks, all is well.

Went for a trip around the block (5 miles), and during acceleration all seems well. Pull back into the driveway and the idle seems pretty smooth (no signs of missing). I then start her back up within a minute, and now she runs really rough, and the following codes pop up:

P0300
P0301
P0302
P0303
P1135 (my old friend from before)

I drive it back into the shop and shut it down.

So what damage was done from the overheating on the Interstate? Like I said, it was running rough pulling into the shop before I did anything to it. For that reason, I don't think my cleaning of the MAF sensor nor the TB caused the symptoms I'm seeing, but they sure are very similar to what others have reported after doing a TB cleaning.

Should I start by doing a compression test to see if the heads or head gaskets might have taken a beating the radiator running out of coolant?

Or should I begin looking at spark issues (check plugs, wires, coils)?

Or perhaps fuel injectors?

Just seems odd to me that the misfire issue would have been caused from the overheating unless the block or head(s) got messed up from what I can only assume was a pretty severe overheating event.

I'm already out like 3 bills and sure hope my block/heads aren't messed up. I guess the only good news so far is that the transmission seems to be ok.

I would do a compression test. From what I've read, these engines do not take overheating well. It often ends badly.

That would be a good place to start. You didn't forget to plug anything back in when you were clean the MAF or TB did ya?

I'm confused how you're radiator could be bone dry of coolant when all that came undone was a transmission line. That shouldn't cause any coolant to come out. Something isn't adding up...

Clearly in your picture, there was some kind of coolant leak in your radiator. There may have been two totally unrelated events. Radiator was leaking for awhile slowly loosing coolant which is what caused it to overheat eventually. That still doesn't explain why the transmission line came out but again, it could be two separate and unrelated events.

Good luck either way, I'll be watching this thread...

Same thing happened to my wife while driving our accord. Not saying all of them but some ladies don't look at the temp gauge. Car overheats, they keep driving and then it stalls. Long story short..blown head gasket and warped head.

I would do a compression test first. Also a pressure test of the cooling system.

Went back out and worked on it some more. 1st thing I did was check to coolant level, figuring I would need to top it off a little now that everything had circulated and cooled back down. I had to add an additional 1/2 gallon. That was way more than what I expected and didn't give me a good feeling at all.

As I was topping off the coolant, I noticed the spark plug wires were probably the originals and one of them had the outer rubber worn down pretty good.



Removed the intake hose and noticed the following in the elbow that goes right in front on the TB. I had just completed cleaned that elbow this morning...



And it is coming from this hose:



Figured it was time to pull the plugs and do a compression test. Here are what the plugs looked like:



#3 was soaking wet and smelled like coolant... #4 wasn't exactly new looking either.

Compression test was pretty much what I expected after seeing the plugs.



So is 120 PSI about average for an engine in good working order?

So what's the verdict? Blown passenger side head gasket, or worse? I don't like that milky stuff being pulled into the intake either...

I believe it should be 180-185. Your numbers seem way low.

Hmm, probably not worth trying to fix this engine then. Anyone have any experience with these guys?

TOYOTA TACOMA 4RUNNER T100 TUNDRA 3.4L V6 ENGINE JDM 5VZ-FE 5VZFE 5VZ | eBay

$899 with free shipping doesn't seem too bad. I'm in Virginia, so not that far from NYC.

Well that sucks, sorry for the lousy news.

A replacement engine is probably the way to go. Tell your wife to keep a closer eye on the temp gauge!

I hate to add insult to injury here, but let's not forget the transmission was over a gallon low. Granted that fluid may have been lost right before the engine died — but the possibility still exist that it wasn't and that damage was done.

Something to consider at least when you are contemplating whether to invest more money in the truck or just cut your losses and move on.

Yeah, I'm trying to decide if it is worth it or not. It's a nice Pearl White Limited 2002 with no rust or collision damage. Just had new tires put on it all around in the fall.

In the wife's defense, the dash bulbs are burned out, so the dash is dark at night. Had that one on my to do list for a while.

Still very odd that the radiator was bone dry, I would have expected there to be SOME coolant left. I checked the spot where she parks it, and there was a little bit of transmission oil right below where the radiator was. I would have noticed that spot pretty quickly even if not looking for it, so the leak must have just started within the last day or two of the fatal episode.

Yikes Yikes Yikes.

1. Ok first off, the CEL isn't just for fun, ya know? Your 4Runner was trying to tell you there's a problem. You just need a front O2 sensor and your 1135 code is gone. $40 on Amazon. BUT, since you've been running with a busted sensor for so long, it's probably been running very very rich.

2. Then, replace the spark plugs and wires. #4 is just as alarming as #3, something literally burned up in that chamber. Coolant feels a little greasy/wet, might also be fuel but gas evaporates fast so you'd be able to tell. If it's coolant you have a blown head gasket. Not the end of the world. #4 looks like it was tossed in a fireplace though. $15 for plugs and $30 for wires. Use plugs that match the ones you took out, either NGK's or DENSO's. Copper is best, no platinum/iridium since it's not needed.

3. You might still have issues after you get a new head gasket installed. Hard to say. I fixed up a 4Runner with a mis-diagnosed head gasket issue only to find out compression was strong and was just leaking coolant at the water pump. Engine was just fine. I will say these engines can take a beating and still be revived. Unless you hear some odd bumps/clunks when the engine is running I say fix it.

4. That watery/oily stuff coming out of the intake is from your PCV valve. It's supposed to only let vapor out but I'm guessing the hose is clogged and the actual PCV valve is broken. Fix that and you won't have the oily intake and the dirty throttle body anymore. $10 fix. Be sure to buy a new grommet too, the old ones disintegrate.

gamefreak,

You're right that I should have deals with that 1135 code a long time ago...

And yes, those are likely the original plugs and wires from 14 years and 196k miles ago.

Those are easy fixes. Looks like I can get a full set of gaskets and new head bolts for around 70 bucks. I suppose that would be worth a shot.

Here are some videos from when I first started it up:

https://youtu.be/rx_JgucDpVQ

https://youtu.be/FF5GNlbnqsk

And here is after a short drive after shutting it down for about 5 minutes and starting it back up:

https://youtu.be/lyiQYvr3xYI

https://youtu.be/RGp4Nw7uIQ8

So no odd bumps/clunks when running, but there is some ticking for sure. That was there before too, so maybe it is just a blown head gasket?

Would it be worth it to have the head checked to make sure it is not warped while I have it off? Is that something that I can do myself and if so how?

Thanks

Get another engine. Don't waste your time.

I have to ask how did your wife drive at night. Is she a Terminator? Did she have a bright flashlight inside the cabin?

High Temp Alarm!!

For the safety of your next engine (and anyone else interested) get yourself an UltraGauge next time.

It allows you to display engine temp (as read through the OBD2 port). Also it allows you to set a high temp alarm at any value you choose. So next time your engine heats up the beeping alarm will get your attention long before the factory gauge even registers the change. You could pull over and check things out a little sooner.

They are cheap too. Around $60 I think.

After studying the process for changing head gaskets on these engines, I think it will be quicker to just swap the whole engine, and eliminate a lot of unknowns with regards to what else might be wrong with the current engine.

So if I go with a JDM sourced engine, I understand that I need to trip it down to the long block and transfer everything else over from my existing engine, including the oil pan. So is a lower oil gasket kit all I need, or do I need a "full" kit, which also includes the head gaskets?

Another option would be a junk yard pull for about $150 around here, but the engine condition would be unknown.

Checked out the UltraGauge. That thing is pretty cool. Will definitely throw one of those on there.

To clarify, it is just lights in the dash that are not working, the head lights function fine, so the wife can see the road in front of her at night.

Not good. Sorry to hear!

Thanks. Yeah it really sucks. I decided to go ahead and drain that expensive ass pink coolant back out. I was able to recover about 2.5 gallons, so about 0.5 gallons is still in there.

Next I drained the oil and found where that other 0.5 gallons of coolant went. What you see in the below pic is fresh oil that was just put in day before yesterday and has about 5 miles on it.



Figured I might as well remove the hood and prep for pulling the engine.



I took a look all around and was wondering about the hose with arrow to it in the below pic. Is that an oil line of some sort? I need to disconnect it by the fitting near the arrow before I can pull the engine.



Hmm, maybe this BMW 4.6L V8 will fit? It is all rebuilt and ready to go!



Just joking. That is another project of mine that has been going on 3 years now. Just look at this mess....





And the holdup. Putting the transmission back together...



So yeah, doing another engine swap, especially a JDM one, is probably not going to end up being a weekend project...

Hope you didn't forget to do the coolant crossover tube on that bimmer engine while it's out

Sorry to hear about the 5vz. It definitely looks like the rest of the truck is worth the money and effort to revive with a new drivetrain.

pclausen said:

I took a look all around and was wondering about the hose with arrow to it in the below pic. Is that an oil line of some sort? I need to disconnect it by the fitting near the arrow before I can pull the engine.

Click to expand...

That is a pressurized fuel line. Surprise!

Swapping out the engine on the 4R should be a piece a cake compared to putting that tranny back together.

Good luck