IS250 Problems
Thread Starter
Driver School Candidate
Joined: Jul 2021
Posts: 8
Likes: 1
From: CA
IS250 Problems
Hello i have recently been having problems with my 2009 IS250.There is a slight tapping noise and engine bay is louder than usual, My acceleration was hesitating for a couple days and then eventually i got the flashing check engine light with the engine code P0306 which is a misfire in the 6th cylinder. I then changed the spark plugs and it was running fine. (All of the the ignition coils looked okay). About 3 days later the hesitiaion started happening again. The check engine light came on along with the traction control light. I got 2 codes P0172 and P0175 for too much fuel not enough air. I recently cleaned the MAF sensor and havent had any engine light for about a day. Does anyone know what this could be? I am going to attach a video of the sound that it is making that i mentioned
Video Link -
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Video Link -
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Last edited by Pivin; Jul 14, 2021 at 10:43 PM. Reason: adding video
Driver
Joined: Jun 2021
Posts: 78
Likes: 14
From: FL
To me the sound sounds like one or more of the pulley bearings are bad....usually a tensioner pulley will be the first to go...but it could be anyone of the pulleys that has a bearing.
Use a mechanics stethoscope (carefully) to find the source of the sound. You can see on many of these pulleys the center bolt doesn't move...so you can place the stethoscope's tip on that bolt.
the P0172 and P0175 both state that the Upstream O2 sensors are reporting a Too Rich condition. Seeing that BOTH upstreams are reporting a rich I'd say the sensors are fine.
So WHAT would make an overly rich mixture?
if the MAF is reading wrong, the ECU could throw more fuel through the injectors.
Do you have an ODB2 scanner that can read live data?
Frankly replacing all the spark plugs from the p0306 wouldn't have been my first choice.
I've been learning A LOT from this guy DiagnoseDan
Narrow/wide band O2 Sensors -
ultimately a dirty MAF(but the diagnostic steps with some tools is important) -
I would, initially, focus on the MAF....but I suspect that what caused the P0306 is not fixed....just hasn't reared its ugly head yet due to new spark plugs.
just my 2 cents
Use a mechanics stethoscope (carefully) to find the source of the sound. You can see on many of these pulleys the center bolt doesn't move...so you can place the stethoscope's tip on that bolt.
the P0172 and P0175 both state that the Upstream O2 sensors are reporting a Too Rich condition. Seeing that BOTH upstreams are reporting a rich I'd say the sensors are fine.
So WHAT would make an overly rich mixture?
- there is less air coming in (clogged air filter? mice in air filter)
- the injectors are staying open longer (being told to do so from the ECU)
if the MAF is reading wrong, the ECU could throw more fuel through the injectors.
Do you have an ODB2 scanner that can read live data?
Frankly replacing all the spark plugs from the p0306 wouldn't have been my first choice.
I've been learning A LOT from this guy DiagnoseDan
Narrow/wide band O2 Sensors -
I would, initially, focus on the MAF....but I suspect that what caused the P0306 is not fixed....just hasn't reared its ugly head yet due to new spark plugs.
just my 2 cents
Thread Starter
Driver School Candidate
Joined: Jul 2021
Posts: 8
Likes: 1
From: CA
I thank the reponse , Yes I agree that the problem isnt fixed. I dont have an OBD2 that can read live data but im gonna get one for this problem and for future problems. Im going to check the air filter today. If it is the ECU telling the injectors to put air there isnt much i could do to fix it ? would the next step to replace the whole ecu or take to a professional technician to repair.
Driver
Joined: Jun 2021
Posts: 78
Likes: 14
From: FL
Replacing the ECU would be the very LAST thing to do AFTER it has been diagnosed as being faulty....those things are expensive.
I've been reading about dirty intake valves caused by the GDI (gas direct injection) engine configuration. That COULD be something you are experiencing (outside of the noise)
These guys SAY that it takes care of the dirty intake valves...I'm new to the lexus family and new to GDIs (apparently the IS350 doesn't have the problem as they implore a port injector too which washes the back side of the valves)
https://www.bgprod.com/services/gaso...air-induction/
I'm going to give it a try as preventive maintenance once a year....others have done a seafoam treatment through an EVAP port (similar to what the BG service is...but way cheaper).
1 - get the noise fixed first
2 - get a scanner that shows live data and we'll go from there.
Finally getting a chance to to view the video. There seems to be engine coolant crust near the crank shaft pulley. Could it be a bad water pump? It's common on these cars. I myself haven't experienced it, and I'm at 112k miles sor far.
Search on Google, or search threads on CL. Many forums on this topic already. Another for now is let the engine cool down, and check your coolant level at the radiator cap.
Search on Google, or search threads on CL. Many forums on this topic already. Another for now is let the engine cool down, and check your coolant level at the radiator cap.
Driver
Joined: Jun 2021
Posts: 78
Likes: 14
From: FL
Finally getting a chance to to view the video. There seems to be engine coolant crust near the crank shaft pulley. Could it be a bad water pump? It's common on these cars. I myself haven't experienced it, and I'm at 112k miles sor far.
Search on Google, or search threads on CL. Many forums on this topic already. Another for now is let the engine cool down, and check your coolant level at the radiator cap.
Search on Google, or search threads on CL. Many forums on this topic already. Another for now is let the engine cool down, and check your coolant level at the radiator cap.
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Thread Starter
Driver School Candidate
Joined: Jul 2021
Posts: 8
Likes: 1
From: CA
Had a minor accident only cracked the front bumper no other damage a while ago . And I drive the car pretty easy for the most part but I’ve had a couple fun drives haha I don’t abuse it .and yes the engine bay has all the covers I just have them removed for the video
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Thread Starter
Driver School Candidate
Joined: Jul 2021
Posts: 8
Likes: 1
From: CA
The injectors wouldn't be putting more air...rather putting more fuel.
Replacing the ECU would be the very LAST thing to do AFTER it has been diagnosed as being faulty....those things are expensive.
I've been reading about dirty intake valves caused by the GDI (gas direct injection) engine configuration. That COULD be something you are experiencing (outside of the noise)
These guys SAY that it takes care of the dirty intake valves...I'm new to the lexus family and new to GDIs (apparently the IS350 doesn't have the problem as they implore a port injector too which washes the back side of the valves)
https://www.bgprod.com/services/gaso...air-induction/
I'm going to give it a try as preventive maintenance once a year....others have done a seafoam treatment through an EVAP port (similar to what the BG service is...but way cheaper).
1 - get the noise fixed first
2 - get a scanner that shows live data and we'll go from there.
Replacing the ECU would be the very LAST thing to do AFTER it has been diagnosed as being faulty....those things are expensive.
I've been reading about dirty intake valves caused by the GDI (gas direct injection) engine configuration. That COULD be something you are experiencing (outside of the noise)
These guys SAY that it takes care of the dirty intake valves...I'm new to the lexus family and new to GDIs (apparently the IS350 doesn't have the problem as they implore a port injector too which washes the back side of the valves)
https://www.bgprod.com/services/gaso...air-induction/
I'm going to give it a try as preventive maintenance once a year....others have done a seafoam treatment through an EVAP port (similar to what the BG service is...but way cheaper).
1 - get the noise fixed first
2 - get a scanner that shows live data and we'll go from there.
Thread Starter
Driver School Candidate
Joined: Jul 2021
Posts: 8
Likes: 1
From: CA
Finally getting a chance to to view the video. There seems to be engine coolant crust near the crank shaft pulley. Could it be a bad water pump? It's common on these cars. I myself haven't experienced it, and I'm at 112k miles sor far.
Search on Google, or search threads on CL. Many forums on this topic already. Another for now is let the engine cool down, and check your coolant level at the radiator cap.
Search on Google, or search threads on CL. Many forums on this topic already. Another for now is let the engine cool down, and check your coolant level at the radiator cap.
Thanks
Intermediate
Joined: Jun 2011
Posts: 427
Likes: 57
My MAF went bad around 150k miles and I also had to replace the idler and tensioner bearings around the same time. My engine sounded nothing like yours. It almost sounds like a bad bearing in your A/C compressor or alternator.... or water pump.
Thread Starter
Driver School Candidate
Joined: Jul 2021
Posts: 8
Likes: 1
From: CA
I agree it sounds like a bad bearing I will let you know when I research further 👍
Driver
Joined: Mar 2020
Posts: 174
Likes: 35
From: Auckland
Finally getting a chance to to view the video. There seems to be engine coolant crust near the crank shaft pulley. Could it be a bad water pump? It's common on these cars. I myself haven't experienced it, and I'm at 112k miles sor far.
Search on Google, or search threads on CL. Many forums on this topic already. Another for now is let the engine cool down, and check your coolant level at the radiator cap.
Search on Google, or search threads on CL. Many forums on this topic already. Another for now is let the engine cool down, and check your coolant level at the radiator cap.
Intermediate
Joined: Mar 2021
Posts: 364
Likes: 64
From: MO
Scrolling through posted threads, one mentions cracked resonator throws ECU codes. The vehicle suffered a minor front bumper hit, maybe the box is slightly cracked and has gone unnoticed...?!
I watched the video, sounds to me like a bad bearing. Easy, well kind of, to figure out, loosen up tensioner belt and spin each of the pulleys. They should feel smooth but with some resistance, sign the BB packet is solid. If it spins endlessly like a skateboard wheel, is reaching the end of its life. Excessive play, grinding noise, and rough, bb pulley is toast and needs replaced.
I would have liked the video be taken give it a few bleeps of the throttle to see if the clanking progresses following the throttle movement (vehicle in P and E-brake of course).
I watched the video, sounds to me like a bad bearing. Easy, well kind of, to figure out, loosen up tensioner belt and spin each of the pulleys. They should feel smooth but with some resistance, sign the BB packet is solid. If it spins endlessly like a skateboard wheel, is reaching the end of its life. Excessive play, grinding noise, and rough, bb pulley is toast and needs replaced.
I would have liked the video be taken give it a few bleeps of the throttle to see if the clanking progresses following the throttle movement (vehicle in P and E-brake of course).
Thread Starter
Driver School Candidate
Joined: Jul 2021
Posts: 8
Likes: 1
From: CA
haven’t had the chance too when I do I’ll let you know thanks I appreciate it. I had some thoughts that it might be the water pump from some reading online so I’ll check