Tacoma overheating

I have a 2006 Tacoma, 4.0. I'm not loosing any coolant. This thing is acting crazy. First of all it acts like I have no circulation at an idle. Regardless of how long it sits and idles it will not blow any heat until you raise the rpm's past an idle. I can drive it all day and it will not start to overheat until you stop for a short period of time and let it idle.(like at a slow drive through) Once it starts to overheat it will continuously clime almost the the read line and fall back to normal for the rest of the trip. While it is climbing it does not blow heat until it starts to fall back to normal. It has 312000 + miles on it. At 250000 I had to replace the head gaskets at which time I replaced all wearable parts that I had to remove to do the job. Timing chain, gears, guides and tensioners, water pump, thermostat, oil pump, idler pullies, belt tensioner and belt.
The only code I'm getting is for catalytic deficiencies on bank 1.
I have done a test for exhaust gases in my coolant system and it was negative. I am getting a few small bubbles coming into my recovery tank which leads me to expect a possible head gasket issue again. If this is the case is it possible the catalytic converter help cause the recurring issue as I had the same code at the 250000 mile mark. I used a camera then to determine I was getting a coolant leak into cylinder #6 which is on bank 1.
The truck starts and runs great with absolutely no rust and has a new frame with accessories thanks to a Toyota recall. I plan on keeping it till it or me dies so any help would be greatly appreciated.

 

Sounds like an air pocket in the engine cooling jacket.

Park it nose up on an incline and warm it up with the radiator cap off. Then massage the hoses while running. It may take some time.

 

Can that happen without opening the system? The truck did great for 60000 miles after the head gasket repair.

 

if you are losing coolant, yes it can happen

 

I'm not losing any coolant but I will give it a try. Any other suggestions?

 

Could be a bad thermostat I suppose.

 

I have a new water pump and thermostat to install along with an idler that's got a squeak. I'll see how that goes. Just wasn't looking forward to possibly replacing head gasket again. That was an all-day job.

 

Not sure how these head gaskets normally leak but if it's an internal leak you'll have coolant in the oil and vice versa. Could do an oil change and send a sample off to blackstone-labs.

A compression test on all the cylinders would be good information too. If some are low that could indicate a blown headgasket.

 

Did the oil change and lab check, negative. I will do a compression check to see whats going on. I,ll hollerback

 

Well I finally gotterdone. After using a camera in each cylinder, I found that I had a small leak coming into Cylinder#6 after a hard run. I tore it down and took both cylinder heads to my local machine shop and had them straightened up and pressure tested. Only cost me $80 for the pair. Put everything back together. Now at 318000 she's running cool and normal, I have heat at an idle again, no temperature spikes and not losing any coolant. I don't even have the bubbles coming into my revisor anymore. I hope this may help someone else in the future. I kind of knew what the issue was but really wasn't looking forward to pulling it apart again. I guess sometimes you're better off to just getter done than to beat around the bush.

 

Glad you got it figured out and running back the way it should be. Not glad it was the head gasket as it's the most expensive type of repair.

 

Thanks, It wasn't too bad, spent about $400 and a couple of band aids from skind up knuckles. LOL

 

I have FINALLY learned, after about 1000 scars on my hands [part of my job was HVAC type work] that thin cut resistant gloves are life [or blood] savers. EVERYTHING on HVAC stuff is sheet metal with a razor blade edge. My DNA is spread far and wide......