High Fluctuating Idle after dormant start.

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kylefav390
Posts: 212
Joined: Wed Nov 20, 2013 4:17 pm
Location: Massachusetts, U.S.

High Fluctuating Idle after dormant start.

Post by kylefav390 »

Hi All, currently a little baffled with my e24. It is an 88' that was auto now swapped to 5-speed. The car has been on jack stands for awhile doing a 5-speed swap and replacing the head gasket. Anyway Last spring of 2021 I got it fired up for the first time since I initially took it off the road in 2018 and it idled and ran fine (although loud from open headers). So since then it has sat basically dormant. Today I finally put coolant in it charged the battery and basically got it ready to go back on the road, but when it started today the RPMS shot up to probably 3000 then would drop back down in a constant fluctuation between what sounds like 3000 RPM and 1000RPM. I'm somewhat at a loss since nothing has really been changed or worked on since I first started it and it ran fine. As far as I know there are no major vacuum leaks that I missed that would cause something like that. Any pointers would be welcome, Thanks a lot!
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Ralph in Socal
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Re: High Fluctuating Idle after dormant start.

Post by Ralph in Socal »

Experienced some odd idle and running conditions on an 88 528e which is Motronic 1.3

Did a system reset by disconnecting both battery cables then holding the cable ends together for 15 seconds. Worked out well

Ralph
There is a very fine line between "Hobby" and Mental Illness.

85 635csi Zinno Auto
84 528i Euro
83 635 Euro Arktik
81 528i Kastanien 5-speed
88 528e Bronzit (Granpa Car)
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kylefav390
Posts: 212
Joined: Wed Nov 20, 2013 4:17 pm
Location: Massachusetts, U.S.

Re: High Fluctuating Idle after dormant start.

Post by kylefav390 »

Ralph in Socal wrote: Fri Mar 11, 2022 9:43 pm Experienced some odd idle and running conditions on an 88 528e which is Motronic 1.3

Did a system reset by disconnecting both battery cables then holding the cable ends together for 15 seconds. Worked out well

Ralph
Interesting, I'll have to give that a shot thanks!
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