Overheating (again) + sputter start = end of Camry?

[Redline]

Need some opinions with my current situation:

My Camry has started to overheat...again. It happened last year (around Sept.-Oct.)...severe overheating. Cause: cracked cylinder head. After poor diagnosis and lots of money spent, the Camry was finally back in my hands with a welded and cleaned cylinder head and new gasket. Now, 6 months later, the Camry is overheating again. The temp gauge doesn't go up as fast or as far, but it still goes up. Since it's only spring with balmy outside temperatures, I'd hate to see what happens when it gets to the hotter temperatures in the middle of summer.

Took it to the dealership and asked for a checkup (with an explanation about the previous repair)...was told that the machined head has less material to dissipate heat as quickly, resulting in a higher gauge reading. But I'm thinking to myself: "perhaps, but it shouldn't be THAT high (3/4 of gauge)". Today, I was driving in 19 degC weather, and the car started overheating again. I'm pissed because I don't know what the cause is now...if it's crap workmanship on the mechanic's part (from first repair) or something different.

Second thing I encountered today: Parked the car in a lot for lunch. It was overheating a bit (3/4 gauge) prior to lunch. WHen I came back and tried to start the car, the thing sputtered and died. I tried several more times, with the same result. I encountered a similar symptom when the butterfly valve inside the air filter box became stuck open, flooding the engine with too much air and not enough fuel at ignition. So I decided to check that....valve was closed, but when I replaced the filter and tried starting again, it worked. Somehow, I feel that there's another reason.

Anyways, I'm describing all this in hopes that someone would be able to help me out in figuring out the problems. I'm thinking of taking the Camry to another mechanic (T-Lex...here I come!), but I wanna know what's going on first.


Is this the end for my Camry?

[Stealth]

Originally Posted by Redline

I encountered a similar symptom when the butterfly valve inside the air filter box became stuck open, flooding the engine with too much air and not enough fuel at ignition. So I decided to check that....valve was closed, but when I replaced the filter and tried starting again, it worked. Somehow, I feel that there's another reason.

There's a butterfly valve in the airbox itself? or do you mean the throttle body?

[Toysrme]

was told that the machined head has less material to dissipate heat as quickly, resulting in a higher gauge reading.

Total load of crap they're feeding you. A 3vz-fe runs 10-20F (all things depending) too cold anyways. Toyota over-did it on the cooling a bit.

I encountered a similar symptom when the butterfly valve inside the air filter box became stuck open, flooding the engine with too much air and not enough fuel at ignition.

You mean the air-flow meter. If it's stuck open, the engine will flood itself with fuel (not starve itself of fuel as you are describing) If you look at this flap, it should be just a tiny bit open at idle, and should move in syncronization (slight hesitation behind) with the throttle opening. (just pull on the level and watch)

Another simple way to test is is to turn the key to the ON position, reach in and push the flap open. You'll hear the fuel system turn on even tho the engine is not running.

If you have a volt / multi-meter, and are not afraid to tap into a wire (I'll show you which later):
The reading engine OFF, key in the ON position should be around 4.5v range.
Idling it should be around 4.2v
Wide open throttle it should go DOWN to 1v - 1.5v

I fairly seriously doubt the AFM itself went bad.





Redline I would almost bet the cooling system is plugged, thermostat isn't opening, or the head gaskets are re-blown.

In any case of those three, I would argue the mechanic into the ground to fix everything, as they're responcible for flushing the cooling system out when they take the heads off. Stands to reason if they do their job and clean it out, it shouldn't be plugged.

Start with the T-stat

[Toysrme]

Check the ignition timing too, as that will reveal if they got 1 out of four camshafts in the correct position (jumper diagnostic terminals E1 and TE1, timing light should show 10* before top dead center on the marker)

[rusty9]

toyrme has some good advice but you should also check to see if the fan is coming on at all too. a quick check is to unplug the coolant temp sensor when the engine is hot but not running (key on tho) the fans should kick on right away. if they dont come on that means theres a fault at either a fuse or relay(expensive green relay about $92 list, but free at a junkyard)

[Redline]

Toysrme: yes, thank you for clarifying the issue. Yeh, it's the AFM...and that hissing sound is the fuel system coming on. Man, I had the right idea, just had it in reverse anyways, I s'pose that the cooling system is plugged, and I sure as hell hope that the gasket isn't reblown My dad and I are gonna go to the mech and have a chat with him about this issue. They should have a warantee that covers repairs for a year. I think they did a flush of the cooling system, so I don't know why it would be clogged again. I also did the T-stat replacement myself before giving it to them to solve the overheating problem last time. I KNOW I put it in correctly. One more thing: if they did a weld job on a s'posed "crack" in the cylinder heads (that caused the overheating), could it be possible that the weld has failed? What would cause it to fail? I'll let you know the situation when I get back from the mech tmr.

rusty9: I've checked the fan to see if it came on while idle...it runs. Not sure how much air it should be pulling in (mass air flow per meter OR cubic inches of air), but it should be fine. Thx for the input!

If anything, I'm thinking of replacing the cylinder heads if it IS a failed weld. Anyone out there know how much it costs for a set of 3vz-fe cylinder heads?

Redline

[Toysrme]

The cooling system on non - 5vz block engines is a hydrolic fan. If the crankshaft is spinning, the power steering pump is pumping fluid. If the power steering pump is pumping, the fan is on so... Nothing useful there, but a good idea.
Redline what kind of fluid was in it before, and what kind is in it now?

If they were mixing any typical green stuff we've used in the US for 50 years, and you had Toyota red in it...


They just bought you a new radiator, and a trip to a block flushing machine.