Date registered: Apr 2019
Vehicle: 1987 190e 2.3
Location: Houston, TX
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intermittent O2 Waring light + Hard Start/Stumble
Hello. New Member here.
A little about myself and my car:
I've recently acquired a 1987 190e 2.3 with ~ 73k on the odometer and in what I generally consider very well maintained condition.
I should also maybe add that this is my first non-diesel Mercedes, but that I've owned and cared for six Volvo 240 daily drivers, several of which were K-Jet equipped and that I'm at least fairly knowledgeable about the mechanical side of the systems operation.
The electrical side of things - the "E" in KE-Jet, as it were - I'm still getting caught up to speed on. And that's why I've come here looking for some possible guidance.
The car generally runs, drives and idles well enough. However, its started having a hard cold start and stumbling stalling issue.
Any time the issue crops up the 02 warning light with come on. Light on = Problem. No Light = No Problem.
The O2 sensor has been replaced (it appears) fairly recently with a universal splice-in type. I've also replaced by the OVP and fuel pump relay. And I've checked the wiring between the ECU/Lamba control unit and the O2 sensor.
When the car is warmed up and running well and I try to take a reading between pins #2 and #3 on the diagnostic socket I get a steady 2.7 volts. No fluctuation. When I take a reading directly from the O2 sensor plug under the passenger-side carpet I get a variable reading that bounces between about ~118-122 mV.
Are there any other sensors tied directly into this circuit that could be causing an issue/interrupt? Otherwise I'm wondering if my ECU isn't just slowing starting to fail.
Thanks in advance,