Prius Project back on the road...slight hickup.

The Gen 3 is back together after getting a new (well, new to me) input damper and a thorough cleaning of the EGR system and intake manifold which were both fouled and/or clogged. The test drive went well, although the ICE occasionally didn't come on until 25 mph or so which surprised me. Most times, it came on around 15 mpg. The car was a bit noisier than I expected (although far less noise than before with the broken input damper springs) but it does have 185K or so on it. The noises didn't sound like internal engine issues but could be small exhaust leak or just normal noise for a high mileage car. I drove it about 10 miles getting up to freeway speeds and it had a little wind noise (driver's side). The only other surprise was entering the driveway at home, it seemed the electric motor revved a bit. I don't know if that indicates a transaxle issue or is normal.

 

There was a hint of rough idle as well which could be related but no check engine light at this point Is there a way to diagnose it or just better to replace? I'm sure it's past the replacement interval anyway.

 

I pulled the PCV valve and it was allowing slight air bypass (when I blew into it from one side) and unrestricted air bypass from the other. So, it was dirty. I shot carb cleaner from both directions and now it seals completely in one direction and allows unrestricted airflow in the other. So, I figure that's correct.

However, now it stored a P0420 code (catalytic converter efficiency) and P3190 (poor engine power) and P3191 (engine does not start) although the engine does start and seems to run well. In addition to cleaning PCV valve, I thoroughly cleaned the EGR cooler, valve, etc. Now, it has deposited some oil in the intake manifold. It was not doing this before, but due to the clogs, it was doing a bunch of other stuff. So, I also added an oil catch can.

Could cleaning either EGR or PCV initiate the oil accumulation problem...do not know.

 

Coolant level looks good. I didn't get any instructions with the catch can and I mounted it maybe 10 inches higher than the PCV valve. I'm not sure that's a good idea and wondering whether that could cause the codes for engine will not start and reduced engine power. Engine does actually start.

 

Interesting kit there. I probably would use it if I'd seen it a couple weeks back. At this point, I've thoroughly cleaned the EGR and intake system (with complete removal) and I put 1.25 oz of SeaFoam in each cylinder when the engine was out of the car. (I asked the SeaFoam tech people about this and they assured me it should clean the piston rings and was safe.) I've put SeaFoam and Cataclean in the gas tank and put CRC intake valve and turbo cleaner through the throttle body. (I've heard this can clean the converter in the same way that it cleans turbo chargers.) I still think the converter might be contaminated so might try more cleaning in place if I can verify that it's not overheating. The car was burning oil previously so I'm sure the substrate is coated. Also, I've probably knocked a bunch of stuff loose in places I really couldn't get to which might be contaminating to the point where it too must be removed.

I took it for a test drive of six miles. Af freeway speeds, Cat te 11 was 1450F. I think that's high but maybe not high enough to destroy it since it declined substantially when I got back to surface streets. It's also gone a couple hundred miles where I didn't monitor temperature.

 

Test Drive Update: The Gen 3 really sounds good and runs well. I used the CRC Intake Valve and Turbo Cleaner via the throttle body to attempt to further clean the catalytic converter. The P0420 code still comes up after 15 miles of freeway driving. But, peak temperature is down from 1450 to 1250. Also, the prior codes for Engine Will Not Start and Low Engine Power have not come back. Considering the two catalytic converter temperatures, the hotter reading is 100 to 300 degrees F hotter than the lower reading. From these readings, I theorize that the CRC cleaner has improved catalytic converter condition although apparently not yet enough to remove the P0420 problem. I'm planning one or two more applications and after that removal and possible replacement of the converter and O2 sensors as I seriously doubt they've ever been replaced in the 180K life of the ten-year-old car.

 

Did you pull the rear Cat pipe loose for drainage? I'd be worried about possible fire inside there. Could blow some compressed air into there as well. I'm getting ready to do O2 sensors so it would be simple to add lacquer thinner.