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I have a bad gas mileage, how about yours ??

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I have a bad gas mileage, how about yours ??

 
Old 02-27-18, 08:18 PM
  #346  
rmk9785e
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Originally Posted by Baetke View Post
Yes, the IAT is part of the MAF sensor. You can get the part number right off the top of the unit. Its in the intake snorkel between the air filter and the throttle body. It has a connector with 5 wires going into it. The part number on mine is 22204-07010.
On second look at your data PIDS I see that there is a line for "Short Term Fuel Trim - Bank 2" and "Bank 2 Sensor 1 Short Term Fuel Trim". This is peculiar. They should have the same value and I don't know why there would be two descriptions for the same sensor. The value on the second one looks reasonable. Can your scan tool plot data? If so, make a graph of the B2S1 data and go for a drive. It should go rich on wide open throttle and lean when you coast. It should be <10% at a steady cruise.
Thank you. My scan tool is kind of old and only runs on Windows with limited ability to graph. Which Bluetooth ODB device and app do you recommend?
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Old 02-28-18, 04:26 AM
  #347  
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Cool use quality gas

It may sound strange but i have found that the cheaper economy gas stations have gas that may have more alcohol content or lacks the additives that quality gas has.I only use brand name fuel and get about 17.1 MPG.
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Old 03-29-18, 10:55 PM
  #348  
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Default P0171 + p1155

Originally Posted by Baetke View Post
Yes, the IAT is part of the MAF sensor. You can get the part number right off the top of the unit. Its in the intake snorkel between the air filter and the throttle body. It has a connector with 5 wires going into it. The part number on mine is 22204-07010.
On second look at your data PIDS I see that there is a line for "Short Term Fuel Trim - Bank 2" and "Bank 2 Sensor 1 Short Term Fuel Trim". This is peculiar. They should have the same value and I don't know why there would be two descriptions for the same sensor. The value on the second one looks reasonable. Can your scan tool plot data? If so, make a graph of the B2S1 data and go for a drive. It should go rich on wide open throttle and lean when you coast. It should be <10% at a steady cruise.
Attached is the best I could do with my current software. I am getting P0171 and P1155 together and the engine idles rough as if it is going to shut down.
Does this provide any hints at what may be causing the rough idle and fuel efficeinecy of around 11 mpg?


The two codes at this time












Attached Files
File Type: pdf
test results.pdf (75.1 KB, 36 views)
File Type: pdf
Fuel Trim.pdf (109.9 KB, 30 views)
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Old 06-27-18, 05:50 PM
  #349  
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I get around 20-21MPG in my 1999 RX 300. Used to be at 15mpg with previous owners, but since i've had the car i used 91 octane fuel and have also given the car several engine cleaners and switched to a full synthetic oil.
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Old 06-27-18, 08:27 PM
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Originally Posted by TechyInAZ View Post
I get around 20-21MPG in my 1999 RX 300. Used to be at 15mpg with previous owners, but since i've had the car i used 91 octane fuel and have also given the car several engine cleaners and switched to a full synthetic oil.
That's impressive if it's in city driving. I'm getting around 15mpg in city driving with regular gas. I didn't realize a combination of higher octane/engine cleaners/synthetic oil could boost it by 25%.
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Old 06-27-18, 09:11 PM
  #351  
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Well I don't do HEAVY city driving, I'd say light to medium amounts, cause where i live there isn't a whole lot of traffic. Mostly HWY driving. But I don't drive like a granny either. My best guess is that there was a lot of sludge in my engine.
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Old 07-08-18, 06:33 PM
  #352  
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Default Your main problem is your Bank 2 A/F ratio sensor 1

rmk9785e,
Focus on P1155 first and ignore P0171 initially (general too lean code usually goes away after you fix P1155).

You should change your Bank 2 sensor 1, that is the one you have easy access from the front of the car. Its electrical (heater) circuit is gone. After that, clear all the codes, drive and see what code comes next, if any. This is your best plan of action. Search this forum and elsewhere, it is not a difficult DIY. There are excellent write-ups on how to fix P1155 (or change B2S1 A/F ratio sensor).

You can buy the Denso A/F ratio sensor (OEM) from Ebay, Amazon, or elsewhere. Don't buy a knockout, buy a Geniune OEM Denso 234-9009, in this case the OEM really does matter due to tight controls on these sensors. I am speaking from the personal experience. Make sure the Toyota or Denso name is on the packaging. Below are some examples, you may find even better deals if you search. (I have no connections to any of the three below, buy at your own risk/reward):

https://www.ebay.com/itm/OEM-AIR-FUE...-/253585820753
https://www.ebay.com/itm/234-9009-De...-/273289772811
https://www.amazon.com/Denso-234-9009-Oxygen-Sensor/dp/B000C5YCZ2 https://www.amazon.com/Denso-234-9009-Oxygen-Sensor/dp/B000C5YCZ2


[QUOTE=rmk9785e;10157749]Attached is the best I could do with my current software. I am getting P0171 and P1155 together and the engine idles rough as if it is going to shut down.
Does this provide any hints at what may be causing the rough idle and fuel efficeinecy of around 11 mpg?
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Old 10-12-18, 08:26 AM
  #353  
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I am still not able to figure out why my car consumes way too much fuel. On a full tank with 50-50 between city and highway, I am getting about 17.5l/100km. That's about 13.44 MPG. Let me add that my car is a 2002 awd European spec. And it has about 183,000 miles on the odo. Any help will be appreciated.

Simon
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Old 10-15-18, 11:16 AM
  #354  
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Originally Posted by ssgi4in12 View Post
I am still not able to figure out why my car consumes way too much fuel. On a full tank with 50-50 between city and highway, I am getting about 17.5l/100km. That's about 13.44 MPG. Let me add that my car is a 2002 awd European spec. And it has about 183,000 miles on the odo. Any help will be appreciated.

Simon
I am getting 15-16 mpg in city driving using regular gasoline with my 2000 RX300 AWD which is at 150,000 miles.
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Old 03-09-19, 11:19 PM
  #355  
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I second that! I inherited an RX and the previous owner said they’d used nothing but mid grade since buying new from the dealership. I came home, filled up with low grade and within a week or so, blew an AF sensor (bank 1). Was an easy fix, but I haven’t had any issues by using mid grade since then.
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