4th Gen DIY heat exchanger bypass solution

Toyota after-sale care, standing behind their product, is notably lacking. I get that there’s a simple workaround, but is this their new “mission statement”:

ignore, dodge and remain silent when there’s an issue, and eventually all the cars involved will fail or rust out.

 

Any Californian knew would this "fix" pass ca smog test?

 

It depends on how nicely you've got it tucked away. The more OEM the look, the better chances it gets overlooked. They're usually looking at the CAT and ensuring it's either CARB certified or OEM.
If hoses are dangling down there with zip-ties, they'll take notice and look harder.

Hope this helps....

 

2017 Prius here. I just checked and saw P0128 code, which says its the thermostat. Two days ago my car had a lot of white exhaust, but it didn't do that yesterday. My coolant reservoir is dry after just driving 5 miles and I have filled it up now three times in a row. Does this sound like the heat exchanger? Or the thermostat?

 

Probably the heat exchanger. Any signs of pink crust, around water pump or thermostat?

 

id take it to the dealership as they should cover it all and be sure to have them do a compression test.. or.. don't remind them and when they fix the TSB... and next thing you know you need a head gasket.. argue that they didn't perform a compression test and you believe the TSB to be the cause of the now need for a new motor...

 

I did not see any pink crust around those areas. If this is the heat exchanger, how does one remove all the coolant that’s still inside of it? Do they burn it off or do they have to replace the catalytic converter.

 

AFAIK the only option with a leaking Exhaust Heat Recover component is replacement. It’s coupled with the Catalytic Converter, a single “part”, and accordingly quite expensive.

 

Geez, this seems to good to be true:

17410-37A00 - Toyota Parts Deal

Maybe too, you're buying brand new, but it's got the defective welds? There's numerous supersessions, prices $1000~2000 USD.

(I first looked it up on Amayama; they're out of stock, of all the the parts numbers, but at least then you can copy/paste those numbers and search with google.)

 

I would love to take this to the dealership

I don't have this trouble code-- (MIL ON DTC P148F00), but I do have P0128 code. I just called Toyota customer service and gave them my vin and asked if the TSB would cover my car and they said that it is vin specific and that my vin isn't included in this TSB. Do you know if that's true? Because the next thing they told me to do was just go to the dealer and have them diagnose it officially.

 

It's part of the emissions system; check CARB regulations to see if your within Ca state mandates. If you meet all CARB regulations, years and mileages, They are required by state law to fix it for free..... Federal statues are much looser...

Hope this helps....

 

Does the Gen 4 Prius even have a heat exchanger? It'd be overkill (imo) if it does.

 

@Dusttttt you might want to give GM gasketmasters a call and ask them if they know, since I believe they are the ones that figured out the heat exchanger bypass for the Gen4 Prime.

 

Does it ever, infamous for leaking too.

 

thanks for the update, i also moved to ev. all the best!

 

You were not eligible for the fix from Toyota? I think they need someone else making the rules on nonsense like this. For starters they're pushing owners to defeat a pollution control devise, by dragging their feet on the supply of replacement parts,, limitting the claim window, and not ensuring dealerships know all the details, and dang well tell owners about it.

 

Sadly my 2017 prime seems to need the bypass:-( No MIL or CEL, but saw white smoke driving home, so I checked and the coolant overflow reservoir was totally empty… I filled it back up and went for a 10 mile drive, and it only smoked at really high rpm up a steep hill. Overflow reservoir is still full. I don’t wanna bypass unnecessarily… should I wait for a code to throw?

 

Just fyi I’m at 152,000 miles so I can’t get it fixed under warranty.

 

I suggest you bypass up in the engine compartment. If you go in for a smog check and they see that coolant loop, while inspecting the CAT - they may fail you.

Good Luck...