128k miles. No known problem but cleaning as a possible prevention of head gasket problem (not 100% convinced it is the cause). Do not have time to clean the EGR cooler at the same time so just the intake manifold today. EGR will be done next.
A few months ago I use Techstream tool to read my EGR flow and the number it said was about 71% flow, and from my understanding it is quite a healthy safety margin on what is considered good (I think less than 20% would be almost completely clogged).
Followed Merv's Service Secret on YouTube on how to take off the intake manifold. Mostly I use Harbor Freight's clip removal tool but I probably should have used 10mm socket in most of them instead. The clip removal tool sort of partially damage some of the zip tie clip.
After the intake manifold was taken off, what surprised me was the EGR pipe actually doesn't have too much carbon build up, and they could be easily cleaned off using Dawn Powerwash spray into the pipe. The main build up was surprisingly not the EGR but rather the PCV. Most of the intake build up was liquid and sticky, some even have a mozzarella pull like texture whereas the EGR build up is gritty hard carbon. Dawn powerwash spray, tooth brush cleaning, garden hose on jet spray to rinse, repeat. Most of the sticky build up were washed away after about 5 to 7 times. The cylinder head's intake port is mostly sticky goop from PCV and I use 70% Isoproyl and rags to clean. After 4 to 5 spray and clean they are "good enough" as in I see some varnish but no more sticky buildup clean. Color went from black to light brown.
The passage from EGR pipe to intake is small with some build up, but not that clogged. If I spray Dawn Powerwash inside and let it sit for a few mins, the discharge would look dark brown, then gradually becomes light brown, then grey. I am soaking it overnight and see how it goes.
Based on what I see so far, it seems like my usage doesn't build up carbon that much. The same 1.8L engine is probably running with less EGR due to the larger load than a typical Prius (bigger size and weight), it can also be because my vin is after Toyota's TSB on piston ring change (from low tension to normal tension in 2014, mine is after the change). This engine does not burn oil, and after 5k it remains at about 3.8 qt drained, out of 4 qt I put in usually. Typically driven in economy mode, kept throttle within economy zone on the dash, highway at normal speed (around 60-75mph). Oil is whatever 0w20 on discount like Valvoline Synpower, PP, and currently Rotella Gas Truck 5w20.
A few months ago I use Techstream tool to read my EGR flow and the number it said was about 71% flow, and from my understanding it is quite a healthy safety margin on what is considered good (I think less than 20% would be almost completely clogged).
Followed Merv's Service Secret on YouTube on how to take off the intake manifold. Mostly I use Harbor Freight's clip removal tool but I probably should have used 10mm socket in most of them instead. The clip removal tool sort of partially damage some of the zip tie clip.
After the intake manifold was taken off, what surprised me was the EGR pipe actually doesn't have too much carbon build up, and they could be easily cleaned off using Dawn Powerwash spray into the pipe. The main build up was surprisingly not the EGR but rather the PCV. Most of the intake build up was liquid and sticky, some even have a mozzarella pull like texture whereas the EGR build up is gritty hard carbon. Dawn powerwash spray, tooth brush cleaning, garden hose on jet spray to rinse, repeat. Most of the sticky build up were washed away after about 5 to 7 times. The cylinder head's intake port is mostly sticky goop from PCV and I use 70% Isoproyl and rags to clean. After 4 to 5 spray and clean they are "good enough" as in I see some varnish but no more sticky buildup clean. Color went from black to light brown.
The passage from EGR pipe to intake is small with some build up, but not that clogged. If I spray Dawn Powerwash inside and let it sit for a few mins, the discharge would look dark brown, then gradually becomes light brown, then grey. I am soaking it overnight and see how it goes.
Based on what I see so far, it seems like my usage doesn't build up carbon that much. The same 1.8L engine is probably running with less EGR due to the larger load than a typical Prius (bigger size and weight), it can also be because my vin is after Toyota's TSB on piston ring change (from low tension to normal tension in 2014, mine is after the change). This engine does not burn oil, and after 5k it remains at about 3.8 qt drained, out of 4 qt I put in usually. Typically driven in economy mode, kept throttle within economy zone on the dash, highway at normal speed (around 60-75mph). Oil is whatever 0w20 on discount like Valvoline Synpower, PP, and currently Rotella Gas Truck 5w20.
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