Need Flow chart for trouble code
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Need Flow chart for trouble code
I have a 1992 Olds 88, 3.8 thats sets a code 34 ( mass air flow ) and I need a flow chart to determine if it's the maf sensor or if it's something else causing it to set the code. All help is appreciated as it's an expensive part to replace if it isn't the culprit.
P.S. The code is on all the time not intermittent.
P.S. The code is on all the time not intermittent.
#2
Have you tried to clean the MAF? They make MAF cleaner and is sold at auto stores. If not a MAF specific cleaner, they have electronic cleaner.
Also, a clogged fuel injector, or clogged cat can throw a code like this.
Also, a clogged fuel injector, or clogged cat can throw a code like this.
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The ses light has been on for quite a while, but occasionally it will go out. When it does it chugs like it is going to stall, but it never does unless I'm stopped. Then a couple of miles down the road it will chug again and the SES lightwill come on again. It doesn't seem to run bad with the SES light on, when I hook up my scanner it shows that it is going into closed loop and everthing. Has anyone got any more ideas. I plan on cleaning the MAF sensor and throttle body tomorrow. The catalytic converter is only a year and a half old.
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I cleaned the throttle body this weekend. It was a little carboned up but not caked on or anything. It is running a little better, but I still have the SES light and it still throws a code 34 (Maf/ Map Sensor Low)
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replaced MAF
I replaced the MAF sensor Saturday, and it has helped somewhat. I found the flow chart and ran thru it and it came out to be a bad MAF sensor or connection. When I replaced it the SES light went out. But came back on later. Still a code 34. It does go out and stay out for longer periods of time now though. When ever it comes on or goes out it will chug or hessitate. If I'm stpped and it comes on or goes out it will stall. Does anyone have any ideas about this, since all I did was turn it into an intermittent problem. Any help is appreciated Thanks.
#6
I have code 34 on your engine to be MAP sensor
It's confusing because around that time frame, depending on the year and engine it could also mean A MAF sensor
Regardless, if it is a MAF like you thought, and a new MAF sensor didn't help, then look for a vac leak or air intake tube leak or some way that air could be entering the engine where it's not supposed to
Inspect the under sides well, a thin crack could be difficult to spot
Especially on curved lines
Look for loose/disconnected vac lines or air intakes tubes also
If it's the MAP code, that gets set when the voltage from the MAP is too low
As far as I know, the solution is to replace the MAP sensor
It's confusing because around that time frame, depending on the year and engine it could also mean A MAF sensor
Regardless, if it is a MAF like you thought, and a new MAF sensor didn't help, then look for a vac leak or air intake tube leak or some way that air could be entering the engine where it's not supposed to
Inspect the under sides well, a thin crack could be difficult to spot
Especially on curved lines
Look for loose/disconnected vac lines or air intakes tubes also
If it's the MAP code, that gets set when the voltage from the MAP is too low
As far as I know, the solution is to replace the MAP sensor
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Thanks for the reply, I checked out the vacum lines and didn't find any leaks, I changed the plugs last night ( no effect ) . When I drive it on the highway the ses light goes out and I can't find any codes with my scanner. Then when I get into town it will be all right for a little bit and then it will chug and set a code 34. If I'm at a stop it will stall when it sets the code. Getting to be annoying. ( the last time I had this much trouble it was the computer.)