crazy check engine light
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Joined: Jan 2012
Posts: 605
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From: Queen Creek Arizona
crazy check engine light
my check engine light comes on when decelerating and then turns off when speeding up, anyone have any ideas of what this problem could be?
sorry for the noise in the background.
and no codes show up
and no codes show up
Last edited by 84VetteMan205hp; Jun 3, 2013 at 06:09 PM.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
I don't know how your car works, but on my '86 the light is turned on by the ECM. They changed the display to Service Engine Soon -- SES.
The ECM puts a ground on the light to turn it on. Either it's getting grounded somehow in the wiring or the ECM thinks it should be on.
Interesting about the no codes being set. Maybe the ECM is seeing some kind of intermittent condition that it doesn't set a code for unless it's permanent. I don't know of any codes offhand that do that.
I did get a SES light a few days ago while driving that went away after a while. I know what causes that one and sure enough the dreaded code 32 was stored in RAM.
The ECM puts a ground on the light to turn it on. Either it's getting grounded somehow in the wiring or the ECM thinks it should be on.
Interesting about the no codes being set. Maybe the ECM is seeing some kind of intermittent condition that it doesn't set a code for unless it's permanent. I don't know of any codes offhand that do that.
I did get a SES light a few days ago while driving that went away after a while. I know what causes that one and sure enough the dreaded code 32 was stored in RAM.
Last edited by Cliff Harris; Jun 4, 2013 at 02:58 AM.
