Author Topic: 90 Suburban runs rough and dies shortly after filling up.  (Read 11266 times)

Offline Irish_Alley

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Re: 90 Suburban runs rough and dies shortly after filling up.
« Reply #45 on: October 09, 2018, 11:11:19 PM »
Maybe a bad ground?
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Offline 90_suburban

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Re: 90 Suburban runs rough and dies shortly after filling up.
« Reply #46 on: October 10, 2018, 05:34:05 AM »
Might be a bad ground on the cigarette lighter. The scanner gets power from there. Might be causing it to idle high cause it is pulling a ground through the aldl? No telling.


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Offline Irish_Alley

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Re: 90 Suburban runs rough and dies shortly after filling up.
« Reply #47 on: October 10, 2018, 01:13:53 PM »
The cig lighter ground itself on the dash, there's a grounding strip above the ebake pedal. Not sure where the ecm grounds.
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Offline bd

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Re: 90 Suburban runs rough and dies shortly after filling up.
« Reply #48 on: October 10, 2018, 02:17:48 PM »
Connecting some scanners (including Bosch) to OBD-I initiates an ECM service mode that affects idle RPM among other parameters.  It is normal for the idle RPM to increase because of it.
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Offline 90_suburban

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Re: 90 Suburban runs rough and dies shortly after filling up.
« Reply #49 on: October 10, 2018, 02:45:49 PM »
Connecting some scanners (including Bosch) to OBD-I initiates an ECM service mode that affects idle RPM among other parameters.  It is normal for the idle RPM to increase because of it.

That makes sense. They should put a warning lol then people won’t chase a problem that isn’t all there.


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Offline 90_suburban

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Re: 90 Suburban runs rough and dies shortly after filling up.
« Reply #50 on: October 11, 2018, 08:54:45 PM »
Figured I would give an update. I’ve driven it around 100 miles maybe a little more. So far so good. I did have one little stumble in the idle but nothing else. Still running really strong.


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