06 tundra wont start after engine pull/bypass kit

Ive got a 2006 tundra double cab 2wd 4.7L.
Ive had it for about 12,000 miles /2 years now no issues.

I have noticed a hot anti freeze smell the past 3 months. But no signs of over heating.
Today i cranked it up and it had a CEL for p0412. After driving it around 16 miles at lunch it started steaming and boiled the fluid out of the over flow onto ground. Gauge was at half way mark when this happened.
I got it towed to the house and put 1 gallon of water in it and it was full.
Cranked it up let it idle for 15 mins and it stayed dead center of gauge.
So i reved it up and it went to 3/4 gauge and i just cut it off.


So i am in process of replacing the air pump under the intake. Its a very dirty motor. Previous owners just didnt take good care.

Has anyone had this code cause over heating before or am i looking at separate issues?

 

I'm thinking separate issues. SAIP only runs for ~1min at startup and its purpose is to

However, if you have air in your coolant system, it can cause overheating - you need to ensure you're burping the system properly when adding coolant. Likewise, if you recently installed t-stat, the jiggle valve needs to be clocked between 11 and 1 during install.

What work has been done to the vehicle most recently?

What color coolant is in it? (Hopefully red)

That was distilled water you put in it, right?

You confirmed the fan is running, right?

What maintenance do you know was done to the truck prior? Timing belt, water pump and tensioners? Anything else?

Coolant smell can come from any number of things. But not knowing the mileage or history of the radiator, water pump, etc. it's hard to say what it would be.

 

First thing I would do is replace the radiator cap. The system should never overflow at normal temps unless either cap is failed, or there is a failed headgasket letting exhaust gases into the system and overfilling it. This usually also causes overheating so my money is on a bad cap at this point since you say it wasn't overheating when it happened.

Temporarily moderately overheating after needing to add a large amounts of fluid is normal, it means there is still air in the system from whatever happened previously. This usually self resolves after a couple cycles of heating and cooling OR a full burping of the coolant system.

 

You beat me to it. If you're filling the overflow to the top and blowing it out the lid I'd say definitely radiator cap is a good start. I've had that fix that problem for me twice now on different vehicles.

 

Water pump and timing was done 30k ago, no recent work done to truck.

Red coolant
Yes distilled water from a jug
not sure how to check fan

Will replace cap and air pump tonight and see what happens

 

Checking fan: See Aerindel's comment below, I was confusing with electric fan.

When filling fluid, are you keeping the heater engaged and on high to circulate fluid completely? Are you certain the system has been burped properly and isn't holding air?

With no coolant system maintenance done in 30k miles, I'd assume you'd have noticed if the t-stat hadn't been set correctly. I agree with the guys, replacing the cap should be a priority. But I think taking time to properly burp your system is something you can do now, without buying anything, air in the system could also be the cause.

 

Well thats not how a mechanical fan clutch work on jeeps/bmws it will always spin even if its bad. So not sure that the "big ass fan" would just not spin... at all

And the air in the system wasnt there for 30k so im trying to figure out what may of caused the original overheat?

Not sure... ordered air pump and cap

Will try to burp system once i get those installed. Suppose to be my forever truck so i gotta get this thing 100%

 

WAS there an original overheat? You say that the temp gauge was normal when it boiled over...this is not an overheat, this is an over pressure, or normal pressure, and a failed cap.

Yeah, this is correct.

On a mechanical clutch fan....the check is that when cold, you should be able to turn it by hand, with some resistance.

When hot, (as in, after you ran the engine long enough to heat everything up to operating temp and then shut it off) you should not be able to turn the fan, without turning over the engine.

If there is no resistance when cold, only light resistance when hot, or its locked solid when cold, those are all failures of the fan clutch.

 

Fixed that issue , radi cap had exploded into peices ibside of radiator and something jammed my thermostat , replaced both and it was good. Still throwing codes for secondaey air now.

 

SAIP codes, all you can do is replace pump and valves, or bypass. The latter isn't a guarantee of no codes; but it's far cheaper. Knowing the chances of the pump failing again during your lifetime of ownership are almost nil, I'd opt for pump/valves bypass. But it's easy for me to say: Not my money.

 

Well thats where im stuck now, i bought the hewitt bypass kit, all 4 bolts broke so I had to remove the engine to fix them. So i just got it all back together last night.

Now when i go to crank my starter does not turn over at all. Almost seems like power is giing to everything but starter

Note i did break the sensor on the top of thermostat, should have replacement for that today.

I ended up buying a 11' 4runner for my daily but i want my truck back on the road ...

 

If the coolant sensor the ECU uses isn't functioning, the engine will not crank. At least this has been reported by more than one person here.

 

Oh well i hope thats it , got new sensor today got it installed now just gotta get a heat gun to splice in new connector.

 

Got sensor fixed Still no crank, guess imma pull intake this weekend and make sure starter wiring didnt get messed up? No clue what else to try

 

Are these grounds on the correct place or are these even grounds

 

White with black strip is always ground. Hold on let me find a clearer picture to show where that ground should be. It looks about right.

 

Here you go, from @Diablo169 truck:

 

10 4 yah so its not the wires on top of my driver cylinder head..ill get intake off next week and investagate the starter wiring

 

There's also a ground from the back of your block to the firewall, just behind the passenger side head. And a ground from your battery to the fender wall.