When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Hey guys. I need help with the lexus Is 250. I realised recently it looks like my car usually coughs or chokes whenever I push the pedals, most times to the floor. I get VSC ( check engine and antiskid) indication. Using a device I got online, I was able to get the fault numbers as P0172, P0175 and P0101. It actually said ( system too rich). I don't understand what it means. Pls anyone with what I can do will be appreciated. I was thinking maybe there is a problem with the fuel : air mixture. Or maybe there isn't enough air or too much fuel. There is a system not working properly.
It's the MAF that seems bad. When you get rich codes on both banks it's a tell sign that it's the MAF. Not enough air in the mixture. So the ECU is subtracting fuel hence the negative numbers. Positive numbers indicate a vacuum leak somewhere along the lines.
You can try either to clean your MAF first with CRC MAF cleaner, and see if it works. If not I would purchase an OEM DENSO from RockAuto.com the cheapest around. On critical engine management parts. You want to buy from a reputable place.
It's the MAF that seems bad. When you get rich codes on both banks it's a tell sign that it's the MAF. Not enough air in the mixture. So the ECU is subtracting fuel hence the negative numbers. Positive numbers indicate a vacuum leak somewhere along the lines.
You can try either to clean your MAF first with CRC MAF cleaner, and see if it works. If not I would purchase an OEM DENSO from RockAuto.com the cheapest around. On critical engine management parts. You want to buy from a reputable place.
Mike thank you so much. You just saved me.some few bills. I will just try and clean the MAF sensor. It's exactly what's wrong with my car. This forum is awesome.
Mike thank you so much. You just saved me.some few bills. I will just try and clean the MAF sensor. It's exactly what's wrong with my car. This forum is awesome.
Disconnect the negative on the battery first for about 15 mins to erase the learned long term fuel trims. Clean the MAF and install back. Hook up the battery back up. Start the engine and let it idle for about 15 mins without touching the gas pedal. FYI the car probably won't start on the first the try.
After 15 mins turn it off and wait a couple of seconds start it back up. Go drive around to see where the LTFT's are at. If they start shooting up then probably the MAF is indeed bad. Optimal range is around +5 to -5, but the closer to 0 is the best.
Disconnect the negative on the battery first for about 15 mins to erase the learned long term fuel trims. Clean the MAF and install back. Hook up the battery back up. Start the engine and let it idle for about 15 mins without touching the gas pedal. FYI the car probably won't start on the first the try.
After 15 mins turn it off and wait a couple of seconds start it back up. Go drive around to see where the LTFT's are at. If they start shooting up then probably the MAF is indeed bad. Optimal range is around +5 to -5, but the closer to 0 is the best.
Good luck!
Roger thanks. Problem is I am not so good a mechanic but will try my best. Thanks
Hello there! So I have the same codes + P0355 come up when dealership checked why my lexus was stalling/hiccuping on accelarration. I was told that I need to replace mass air flow sensor and quoted $500 for the work. I am assuming that is the same thing as "MAF"?
The weird thing is the hiccuping problem went away after I got my car back. I had declined the replacement work for now but they did do a (courtesy) boost to my battery since that "failed" during their testing. They also recommended I replace the battery. It was 3 years old.
Can someone advise me if the battery operation is related to MAF or was this a coincidence??
Hello there! So I have the same codes + P0355 come up when dealership checked why my lexus was stalling/hiccuping on accelarration. I was told that I need to replace mass air flow sensor and quoted $500 for the work. I am assuming that is the same thing as "MAF"?
The weird thing is the hiccuping problem went away after I got my car back. I had declined the replacement work for now but they did do a (courtesy) boost to my battery since that "failed" during their testing. They also recommended I replace the battery. It was 3 years old.
Can someone advise me if the battery operation is related to MAF or was this a coincidence??
Thank you!
They probably just reset the ECU. So it erases the codes, and and the ECU is on a clean slate. If you problem is bad enough the codes will pop back up
MAF = Mass AiR Flow Sensor
You can buy it from RockAuto.com for like $70 like, and install it yourself. Pretty basic item to swap just two srews, and a harness clip.
I would replace your battery ASAP if it's failing. These cars tend to do weird things with a failing battery.
When installing the new battery. Make sure it's in the right position, or you'll blow your FUSIBLE LINK. Don't hook up the terminals backwards to the wrong POSTS of the battery.
They probably just reset the ECU. So it erases the codes, and and the ECU is on a clean slate. If you problem is bad enough the codes will pop back up
MAF = Mass AiR Flow Sensor
You can buy it from RockAuto.com for like $70 like, and install it yourself. Pretty basic item to swap just two srews, and a harness clip.
I would replace your battery ASAP if it's failing. These cars tend to do weird things with a failing battery.
When installing the new battery. Make sure it's in the right position, or you'll blow your FUSIBLE LINK. Don't hook up the terminals backwards to the wrong POSTS of the battery.
Thanks for the reply. The battery did die next day and I had my AAA guy replace it. So it's all good.
They probably just reset the ECU. So it erases the codes, and and the ECU is on a clean slate. If you problem is bad enough the codes will pop back up
MAF = Mass AiR Flow Sensor
You can buy it from RockAuto.com for like $70 like, and install it yourself. Pretty basic item to swap just two srews, and a harness clip.
I would replace your battery ASAP if it's failing. These cars tend to do weird things with a failing battery.
When installing the new battery. Make sure it's in the right position, or you'll blow your FUSIBLE LINK. Don't hook up the terminals backwards to the wrong POSTS of the battery.
Just a note; I've re-replaced MAF sensors that were not Denso to fix cars that weren't fixed or were only fixed temporarily with off-brand stuff. Read reviews, I suppose and make sure you're not getting a bad sensor.
I've successfully cleaned a ton of MAF sensors but this is not an accepted practice. I highly recommend that you get a magnifying lens and look at the resistors. If they are coated in oil it is easy to clean them. If they are fuzzy, well, you'll need to get creative. There are many ways to clean them. I have a secret method for not breaking them. Good luck!
A P0101 usually sets when the MAF has suffered an internal electrical issue. Without freeze frame date, however, I can't say for certain. If your vehicle is under-volting severely at start up it is possible to set this code.
A P0101 usually sets when the MAF has suffered an internal electrical issue. Without freeze frame date, however, I can't say for certain. If your vehicle is under-volting severely at start up it is possible to set this code.
I have these 3 codes on my Lexus IS250. I’ve replaced the MAF sensor 2 times, all 4 O2 sensors, and there are no vacuum leaks per 5 shops. Not even Lexus can figure out the problem. please help.
09-07-18, 07:05 AM
P0172, p0175,.p0101
