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1998 Lexus GS400 - P0172 - Runs Rich

 
Old 07-04-13, 07:24 AM
  #46  
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Originally Posted by ThomasGS4 View Post
My apologies. So the MAF sensor is the issue?
Based on your readings versus what the readings are supposed to be, I would say yes...

Might be a good idea to recheck air flow rate at 2500 instead of 3000 to make sure though...
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Old 07-04-13, 08:01 PM
  #47  
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Just rechecked with the RPM dead set at 2500, and we're looking at 18.14 g/s.

Last edited by ThomasGS4; 07-04-13 at 08:05 PM.
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Old 07-04-13, 10:26 PM
  #48  
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That is higher than it is supposed to be for sure, just don't know if its enough to cause your issue...
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Old 07-05-13, 03:05 AM
  #49  
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I'll recheck again once I get to work and the car is warmed up, because that's when the symptoms are most prevalent.
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Old 07-05-13, 04:07 AM
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Just checked. I couldn't get the rpm right at 2500, but when it was at 2570, it showed 2.3 lb/min. When the rpm was slightly under, at around 2480, it showed 2.8 lb/min.
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Old 07-05-13, 06:58 AM
  #51  
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You said you tried a different MAF?

Those numbers are a little erratic, I think that's been your problem all along...

2.8 lb/min is 21 g/s, and the spec at 2500 rpm is 16 g/s...
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Old 07-05-13, 08:52 AM
  #52  
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Originally Posted by mitsuguy View Post
You said you tried a different MAF?

Those numbers are a little erratic, I think that's been your problem all along...

2.8 lb/min is 21 g/s, and the spec at 2500 rpm is 16 g/s...
I'm thinking so too. I'll pick up a new MAF from the dealer this afternoon and will check the airflow to see if it's within spec.
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Old 07-05-13, 09:22 AM
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Originally Posted by mitsuguy View Post
You said you tried a different MAF?

Those numbers are a little erratic, I think that's been your problem all along...

2.8 lb/min is 21 g/s, and the spec at 2500 rpm is 16 g/s...
How do you know 2500 rpm is 16g/s is spec?
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Old 07-05-13, 03:02 PM
  #54  
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Well, seems to be all fixed! Hesitation is gone! Part of the problem was, I didn't have the new MAF on previously to determine whether it had fixed the car or not. Guys, I truly appreciate all of the time and effort you have put forth for me.
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Old 07-05-13, 03:49 PM
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Originally Posted by ThomasGS4 View Post
Well, seems to be all fixed! Hesitation is gone! Part of the problem was, I didn't have the new MAF on previously to determine whether it had fixed the car or not. Guys, I truly appreciate all of the time and effort you have put forth for me.
If ya don't mind, post up the fuel trims with the new MAF for comparision.
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Old 07-05-13, 10:54 PM
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Originally Posted by GS4_Fiend View Post
How do you know 2500 rpm is 16g/s is spec?
Because I have access to Identifix and Mitchell... hard as heck to read, but it's in the picture I posted earlier in the thread!!!
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Old 07-05-13, 10:56 PM
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Originally Posted by ThomasGS4 View Post
Well, seems to be all fixed! Hesitation is gone! Part of the problem was, I didn't have the new MAF on previously to determine whether it had fixed the car or not. Guys, I truly appreciate all of the time and effort you have put forth for me.
Glad to help!

What do you mean didn't have the new MAF on previously?
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Old 07-06-13, 06:12 PM
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Originally Posted by mitsuguy View Post
Because I have access to Identifix and Mitchell... hard as heck to read, but it's in the picture I posted earlier in the thread!!!
Hard to read as stated. Where on Mitchell do you see it shows the specs of grams/sec? It only shows you how to test resistance and that's it. I would like to know the algorithm.
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Old 07-06-13, 06:15 PM
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Originally Posted by GS4_Fiend View Post
Hard to read as stated. Where on Mitchell do you see it shows the specs of grams/sec? It only shows you how to test resistance and that's it. I would like to know the algorithm.
Mitchell sucks for that kind of information, which is why we do Identifix too... there is a lot more advanced diagnostic data on identifix, for sure...
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Old 07-07-13, 11:36 AM
  #60  
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Originally Posted by mitsuguy View Post

Glad to help!

What do you mean didn't have the new MAF on previously?
Trying to get ahead of myself, I guess. I meant to say that I didn't have the new MAF I had bought previously on the car long enough to try and determine whether it had fixed the car or not. I was still trying to diagnose whether the car was misfiring or the wheels/tires were out of balance.
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