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Code 44 only when hot

Old Nov 24, 2015 | 09:07 PM
  #1  
Logan Bryant's Avatar
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From: Cambridge City, IN
Car: 1991 RS
Engine: 355
Transmission: TH350
Axle/Gears: 4.11
Code 44 only when hot

Drove my car today and after about 30-40 minutes, it popped up a check engine light and wanted to stall and lose all power. I finally got home and checked the code and got 44 "lean exhaust". I already replaced the fuel filter, O2 sensor and plug wires. My next guess would be the fuel pump.
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Old Nov 26, 2015 | 10:41 AM
  #2  
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From: knoxville tn
Car: 86 IROC
Engine: 5.0 TPI
Transmission: 700-R-4
Axle/Gears: 2.73 open
Re: Code 44 only when hot

do the std tests . is there fuel in the PR hose ? have you run a fuel pressure and volume test ? how old /clean are your injectors ? have you OHMd them yet ?
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Old Nov 28, 2015 | 08:32 AM
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Re: Code 44 only when hot

A fuel pressure test is an easy thing to do.

It could also be a vacuum leak, EGR leak, exhaust leak upstream of the sensor, Air Injection divert/port valve leak, incorrect bias signal to the O² sensor or poor connections to/from the ECM, contaminated sensor, etc. The '85 TPI system is somewhat loose in its monitoring of the O² compared to later versions. The signal has to be pretty low to show a lean condition, something like less than 200mV for the duration of the 50-60 second timer base.
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Old Dec 8, 2015 | 08:23 PM
  #4  
Logan Bryant's Avatar
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From: Cambridge City, IN
Car: 1991 RS
Engine: 355
Transmission: TH350
Axle/Gears: 4.11
Re: Code 44 only when hot

I started to experiment, so I unplugged the maf sensor and it stopped the hesitation when hot.I ran it without it wanting to stall, so for now I have to leave the sensor unplugged. I also ohmed all The injectors and they all came back from 15.6 to 16.

Last edited by Logan Bryant; Dec 8, 2015 at 08:30 PM.
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Old Dec 9, 2015 | 10:47 AM
  #5  
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From: knoxville tn
Car: 86 IROC
Engine: 5.0 TPI
Transmission: 700-R-4
Axle/Gears: 2.73 open
Re: Code 44 only when hot

Originally Posted by Logan Bryant
I started to experiment, so I unplugged the maf sensor and it stopped the hesitation when hot.I ran it without it wanting to stall, so for now I have to leave the sensor unplugged. I also ohmed all The injectors and they all came back from 15.6 to 16.
well , you know what means . time to go through MAF sensor hell , tryin to find a good one . take our advice . dont waste time with amazon , auto zone, advance,. go to oreilleys and get a "rich porter " MAF sensor. part # MA-157
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Old Dec 10, 2015 | 08:16 PM
  #6  
Logan Bryant's Avatar
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From: Cambridge City, IN
Car: 1991 RS
Engine: 355
Transmission: TH350
Axle/Gears: 4.11
Re: Code 44 only when hot

Originally Posted by rusty vango
well , you know what means . time to go through MAF sensor hell , tryin to find a good one . take our advice . dont waste time with amazon , auto zone, advance,. go to oreilleys and get a "rich porter " MAF sensor. part # MA-157
Is the rich porter the same as spectra? It has the same part number. Are you sure it wil work because the inside looks different than mine
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Old Dec 11, 2015 | 12:54 PM
  #7  
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From: knoxville tn
Car: 86 IROC
Engine: 5.0 TPI
Transmission: 700-R-4
Axle/Gears: 2.73 open
Re: Code 44 only when hot

stay away from "spectra"
quality is non existant. same for "A1 cardone" thing is , DO NOT buy a re man unit . make sure it is a NEW one . and yes , part #s are all across the board. and as far as its insides . dont worry , there are at least 3 diffrent designs of them . 86 to 89 are reported to take the same MAF . the key is NEW only
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Old Dec 11, 2015 | 03:44 PM
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Logan Bryant's Avatar
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From: Cambridge City, IN
Car: 1991 RS
Engine: 355
Transmission: TH350
Axle/Gears: 4.11
Re: Code 44 only when hot


Well I have an 85 and I read it uses a different signal than the others do. I don't want to spend $150 on a maf and it not be compatible with my car.
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Old Dec 11, 2015 | 05:58 PM
  #9  
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From: knoxville tn
Car: 86 IROC
Engine: 5.0 TPI
Transmission: 700-R-4
Axle/Gears: 2.73 open
Re: Code 44 only when hot

just buy a new one for your 85
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Old Dec 11, 2015 | 09:02 PM
  #10  
Logan Bryant's Avatar
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From: Cambridge City, IN
Car: 1991 RS
Engine: 355
Transmission: TH350
Axle/Gears: 4.11
Re: Code 44 only when hot

That's the problem. I don't know of a new one made just for an 85.
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Old Dec 11, 2015 | 09:50 PM
  #11  
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From: knoxville tn
Car: 86 IROC
Engine: 5.0 TPI
Transmission: 700-R-4
Axle/Gears: 2.73 open
Re: Code 44 only when hot

granted, it being a one year only deal . could be a minor problem . but dont give up just yet
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Old Dec 12, 2015 | 12:27 PM
  #12  
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From: ARIZONA
Car: 92 Trans Am Conv
Engine: LB9
Transmission: T5
Axle/Gears: 3.08
Re: Code 44 only when hot

Do MAF cars have a speed density backup or is it a limp mode it operates on when MAF is unplugged? I just wonder why not disable MAF codes and get an SD tune?
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Old Dec 12, 2015 | 04:40 PM
  #13  
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From: knoxville tn
Car: 86 IROC
Engine: 5.0 TPI
Transmission: 700-R-4
Axle/Gears: 2.73 open
Re: Code 44 only when hot

yes , when you unplug the MAF it goes open loop. and as for why not go SD . you can
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