I know this has been beaten to death and I've searched as much as I could for more answers but I'm beyond stumped on this one. Its my friends 2015 Prius, had a coolant leak and the "overheat light" come on and go off at one point but it drove fine for several months after his dad replaced the coolant tank. I found this out after replacing the #4 injector (car cleared up when unplugged) eventually replaced all injectors and spark plugs. I cleaned out the EGR ports in the intake manifold, probably not to the best of my ability and EGR valve, which didn't change anything. I then acquired and stuck a borescope down the spark plug tubes finding 3 of the 4 cylinders were wet with what I presumed to be coolant after he told me about it overheating. I did try to pressure test it after hours of running and tinkering, it wasn't loosing any pressure but we decided lets do the head gasket it must be the problem! Well one head gasket later the problem still persist, it would run perfectly smooth at some points but then the rattle would immediately return. Any advice as to were I should look next?
I had the same death rattle until I cleaned the entire EGR system, all pipes and especially the EGR cooler, the cooler was totally plug so that water would not flow threw it at all , once clean problem went away.... Seems like you cleaned everything in the EGR system but the cooler..
100% my 2015 has an EGR cooler. Cleaned mine somewhere around 100,000-110,000 miles (can't remember), and it was pretty gunked up. I'm at almost 142,000 miles (less than a year driving, since I did the cleaning), and I'm already preparing myself for another cleaning soon.
So I take it the updated pistons and rings didn't that the cooler from clogging? Are you burning oil? What type of driving do you do, highway or city? Drive like an F1 driver or Prius driver?
Well, I am not burning any oil or coolant at all. I change my oil somewhere around 5000-7000 miles, but with my driving, that's averaging every two months I do an oil change. I use whatever high mileage full synthetic is on sale at Walmart (right now, QS was like 50 cents more than the Walmart brand, so why not?) I also use whatever filter is easily available... that can be the Toyota one, Wix, higher-end Fram, etc. Never had issues with any of them. When I did the EGR cleaning, I did install a catch can, and that definitely has been catching quite a bit. But I have no real way of comparing if the updated pistons/rings made my cooler less clogged or not. I don't think it was as bad as some have noted here, but it certainly was needed, same goes for the passages in the intake manifold, and the small pool of oil under the the throttle body. I do about 90% highway. My profession is based on driving a lot, and my territory that I work in is about 90-120 miles from where I live, so every weekday I'm driving average of 200-240 miles. I usually try to keep it around 65-75 MPH, and the drive is mostly flat, some uphills and downhills. I lately have been averaging 46-47 MPG, but have easily done low 50's MPG in the cooler weather. Edit: I do use ECO mode almost exclusively, but sometimes I use normal mode if I need a bit more power. Almost never use PWR mode.
Sounds like the type of driving I do. I use Mobil 1 high mileage. $24 at walfart. The cheaper brands probably burn nastier and clog the cooler. And I use Toyota filters from Toyota. They cost less than from anyone else. And they give me a 10% veterand discount. Not burning oil is good. So maybe they did revolve the oil burning. I have a spare cooler so I just switch them. It's a 2 hours job so no biggie. Thanks!
I've used Mobil 1, Valvoline, Walmart/Supertech, etc. Never any burning or issues with them. In fact, even the Supertech meets that DEXOS/GM requirement, so I'm fairly confident it's a good oil. But, again, for the 50 cent price difference, the Quaker State seemed like the a no-brainer. Since I am self-employed, taking care of my own repairs and maintenance on the car is vital to reduce any expenses, so I'm always doing my best to work on things myself at the best cost but not going TOO cheap. I think the oil burning is resolved, but still the EGR system and PCV issues exist. Maybe not quite as significant, but still there. And to be fair, I have had two death rattles before. One time before I did the cleaning, and one time I did about two months ago. Both were after the car sat for a longer period of time (about three days of not running). Again, no oil was burning and coolant level has not changed since I did the water pump & thermostat (right around the same time as the EGR cleaning). However, I was able to source a brand new EGR valve from a dealer near me (it's the "kit" and not the just the valve), and I plan to replace my EGR soon since I don't know how well I cleaned it up the first time. Since I was able to get the kit for a great deal, I will just replace it next time I do the cleaning of the cooler, etc. As for filters, I agree, Toyota filters are so cheap that it makes sense, but sometimes I am already at the store and just pick up something there. But yes, the Toyota filters at a dealer near me are under $5.
I cleaned out the EGR cooler, did a compression test and leak down test with nothing definitive. The spark plugs are constantly fouled out with what smells like fuel and the cylinders look wet with a borescope after sitting, something tells me that is not right. I hate to put in all of this work and throw in the towel but I'm stumped! Perhaps someone can tell me how the EGR valve is supposed to go together, When I disassembled it initially the internal coil or stator (unsure of the name) was stuck, I can screw it down until it sticks the valve closed or am I supposed to leave it to spin up and down on its own?
The valve was not made to be taken apart. A lot of people seem to have problems after putting it back together. Sounds like you have a fuel shut off problem. Either all the injectors are leaking, or you have an electrical problem that is allowing the injectors to stay open. That's where you need to look.
Here’s some pics I took when I had ours out last fall, might be helpful just as visual aids. The last one illustrates a method to keep the screwed-down piece from partially unscrewing when putting the cap back on; there’s a little slot you can put a pin into, keep it from turning.
Should you find yourself needing to actually replace the EGR valve itself, make sure you get the EGR repair kit instead of the just the valve. It's cheaper and comes with the gaskets if you need to replace them, too. The part number to look for is 04004-58137 I think I paid something like $150 at a local dealership for the kit. They had to order it and it took about 3 days, but still better than the valve itself.
So you did run it without the electrical connector plugged in on the egr valve and the system fully mechanically assembled and still in tact? You should get a check engine light when you do it.
