Bad gas or headgasket?

Maybe a good time to look at your EGR cooler and it's pathway which unfortunately goes right into your intake manifold and those little ports in the intake manifold main ports are known to get crap in them and slow down the flow of EGR which the Atkinson cycle engine is dependent upon to run properly without it you get the rattle and the imbalance shaking and so on apparently this is the case so maybe something got moved or pushed with the techron little bit of cleaning now take it a step further I guess or go to the junkyard round you up the intercooler for the EGR gas It's a silver thing since it's right on the top of your car Go buy one from a junkyard get the metal pipe that comes out of the intake manifold and goes into that cooler assembly were buying and maybe get the plastic intake manifold if it's easy to get that way there you can have all those parts cleaned like new and ready to go so on a Saturday midday you can go out unbolt all that mess off your car put on the brand new clean stuff fire up the car see what you got You can also use the Toyota software before you do this and you can measure the flow of the EGR in HG that's going through the system right now and I think it might even show you what ideal is or it's posted here and then you can see how bad you are now and then when you put the clean stuff on see how much it improved obviously with the new numbers for the cleaner parts and a lot of times that will stop your rattling business of course if you do in fact have a head gasket leak You're heading for that JDM engine a lot sooner I have a JDM engine right now that's doing the same thing your car is doing It was doing the same thing in this particular car before this engine anyway yeah I just giving up on the generation 3 for that issue but yeah put a clean EGR setup on there and see what happens of course if you wanted the gate any of this you can just take a camera and look down each spark plug hole usually it's going to be number one and see if you can find any droplets after the car's been sitting say you know an hour wip out the windshield wiper tray pull the coils and plugs stick the inspection camera start with number one obviously and have a look in there real good You see any kind of drops that's water You need not worry anymore about your rattle but that head gasket's going to cause a bent rod if you're not careful.

 

Due to theft, or it failed?

Misfire codes, coolant loss and 156K. I'd be thinking head gasket. But everyone seems to try spark plugs and coils first.

EGR not cleaned?

 

What explains why you were losing coolant and now you aren't? Was there a coolant leak that was fixed (hopefully not by a stop leak chemical added to the coolant)? Bad gas can't cause loss of coolant.

 

That crossed my mind too.

 

Has the high temperature light on the dash ever come on when you were driving the car?

Check around the plastic coolant tank for any evidence of dried coolant. One possible reason that you were losing coolant is a failing engine water pump.

 

Maybe stop leak product added by the shop that “cleaned his EGR system”?

 

Yes, I would change the engine water pump ASAP.

After you remove the old water pump, try spinning the impeller by hand. Is there resistance to it spinning.? If so, try to remove the impeller and inspect the white plastic that is around the magnet. Is the white plastic split? Better yet, upload a photo.

 

Yeah, 156K miles, it's time to change engine coolant pump, aka water pump. If you're doing coolant changes by miles, 150K is the second engine coolant change (and first for inverter coolant, in the States). Timely, maybe even pushing it.

 

Personally, I would only purchase an OEM water pump. They are made by AISIN for Toyota. Do not buy a cheap generic pump unless you want to change it in a year or two again.