Engine Load variable Question with scanner
#1
Engine Load variable Question with scanner
What sensors help the ECM determine engine load? I have an intermittant issue where the engine tries to stall at an idle but doesnt succeed. No codes are being stored and the fuel pump and components are all brand new. Watching my scanner the symptoms occure when the engine load variable changes from mid 50's to 70 and then it tries to stall out then bounces back to mid 50's 60's and recovers before dying completely. Everything else seems to be reading normal so I'm assuming its possibly a vacuum related issue.
Anyone care to take a stab at this one ?
Kaycee
Anyone care to take a stab at this one ?
Kaycee
#2
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Car: 90 RS/90 Z-71/73 Vega
Engine: 3.1/5.7 TBI/5.7
Transmission: 700R4/700R4/350turbo
Axle/Gears: 3.23/3.42/3.42
Re: Engine Load variable Question with scanner
When you say it tries to stall at an idle ...do you mean the cars not rolling ..just sitting at a stoplight/sign or ..is it when your coming to a stop?.
#3
Re: Engine Load variable Question with scanner
It will happen when sitting in neutral just parked or while driving intermittantly. The best way to describe it is, with your motor running if you just click the key off for a second and then instantly back on again killing power to the engine but able to recover without restarting it. The engine doesnt completely stall out in both situations. The ignition switch is brand new and adjusted properly and checked things with the volt meter and everything seemed in check. The only thing I saw that changed during the isntance it messed up was the engine load according to the scanner. I was in the mind set that when parked and idling there shouldnt be much of an engine load being recorded so wouldnt fluxuate as much as I'm reading currently. Ranges between 50 to 75 parked idling. The MAF sensor was an OE part so I figured with the fluxuations it might have been starting to die. I unplugged the MAF and did the same tests and the dying didnt occur and idle was normal and smooth actually.
#4
Re: Engine Load variable Question with scanner
forgot to mention that all accessories stay powered up and dont flutter with the engine tho the tach guage shows the rpm drop for that second and sometimes I see it shaking a bit and wondered if it was actually drivin by the coil or if the ecm just controlled it. I had a tach on a 74 camaro that the wire from the coil tach lead grounded out and killed the engine and wondered if that could be related since the guauge is showing its strange movements. Just grabbing at straws at this point
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Car: 89 RS 89 iroc 87 firebird
Engine: 3.1 Turbo/ 355 twin turbo
Transmission: a4 w/ 4500 stall/ a4 / t5
Axle/Gears: strange s60 /w 3:42's
Re: Engine Load variable Question with scanner
well u can try taping on the maf withthe handle end of a screw driver.
dosent always work but typically on one thats going out it will make the engine stumble
chances are u have a bad maf sensor
pull out the spark plugs
everytime i had a maf go bad the motor would run lean as hell and turn the plugs white
dosent always work but typically on one thats going out it will make the engine stumble
chances are u have a bad maf sensor
pull out the spark plugs
everytime i had a maf go bad the motor would run lean as hell and turn the plugs white
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