87 Mass airflow sensor
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87 Mass airflow sensor
I'm having a problem with the idle on my 87'. The car starts find, but when ever I try to give it gas, it begin to stumble and shut off. The car actually acts like its flooding out, with too much fuel. I've checked and cleared all my ecm codes. The codes that were stored was a 22 and a 33. I've changed the ecm and adjusted the tps sensor to 4.6 volts. The car is currently not giving a code, but is still doing the same thing. I was wondering is there a way to check the mass airflow meter? Is there any specific voltage values I could look for with my voltage meter to ensure it's working properly. I would really like to know if this is the problem before I go out and buy one.
Thanks
purplehayes
Thanks
purplehayes
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From: SE NY
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The post '85 L98s used two relays for the MAF, one for the MAF power, the other for the MAF BurnOff.
A suggested MAF test is to disconnect the MAF and start the engine; if idle is smoother replace the MAF. This test did not work on my '88; only when I swapped in the MAF from my '86 IROC-Z did the idle smooth out and the engine run normally.
A suggested MAF test is to disconnect the MAF and start the engine; if idle is smoother replace the MAF. This test did not work on my '88; only when I swapped in the MAF from my '86 IROC-Z did the idle smooth out and the engine run normally.
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Along time ago, maybe 4-5 years ago. I had forgot to replug in the mass airflow sensor after cleaning the thottle body. The car was drivable with the mass air unplugged. The only differrence in driving along was when I came to a stop, the car would cut off. Under nomal driving conditions I could notice the car was missing and run rich.
purplehayes
purplehayes
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From: SE NY
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Now my car won't start with or without the MAF plugged.
Any new codes?
You can pick up a used MAF from an F-body car to swap in if all else looks good.
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From: sw Ohio
Try holding the gas pedal all the way down and starting the car, it will help clear a flood condition. Also you might want to check your fuel pressure as that can have a lot to do with a hard starting/rough idle problem.
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Joined: Mar 2008
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From: Bowling Green Kentucky
I'm having a problem with the idle on my 87'. The car starts find, but when ever I try to give it gas, it begin to stumble and shut off. The car actually acts like its flooding out, with too much fuel. I've checked and cleared all my ecm codes. The codes that were stored was a 22 and a 33. I've changed the ecm and adjusted the tps sensor to 4.6 volts. The car is currently not giving a code, but is still doing the same thing. I was wondering is there a way to check the mass airflow meter? Is there any specific voltage values I could look for with my voltage meter to ensure it's working properly. I would really like to know if this is the problem before I go out and buy one.
Thanks
purplehayes
Thanks
purplehayes
Could be a fuel problem instead of a air problem. My car runs fine with or without the mass air flow plugged in. I've actually turned a faster time in 1/4 with it unplugged.
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From: Summerland B.C. Canada
TPS should be .54 volts at idle, your 4.6 would be a WOT reading. Is that a misprint ??
http://members.shaw.ca/corvette86/Code%2033.pdf
http://members.shaw.ca/corvette86/Code%2022.pdf
Melting Slicks
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From: Jasper Texas
My 87 T/A was the same way, plugged in or unplugged, ran just fine. The vette, on the other hand, night and day difference.
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The tps sensor was set while holding the throttle wide open. I would consider the fuel filter, if the fuel pressure gauge on the fuel rail wasn't reading 42lbs. when I turn the ignition switch on. The car will idle, but its running rough. When I press the gas it will only rev about 11 to 13 grand. I'm wondering could it be a firing problem wth my distributor or my 6al msd box.
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