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Higher idling speed

Hi guys,

please let me state a few symptoms I observe, that hopefully look familiar to some of you and which could explain my problem:

1) higher idle: steady between 700 and 1000: sometimes 700, after a few minutes 900, then 800 etc.); no difference when engine is cold or warm 2) increased fuel consumption 3) engine sometimes hesitates to pick up when revving up. 4) constant 'beep tone' from 60 mph up, coming from passengers side:I haven't figured out yet if it's the idle speed relay at the bottom or the idle speed/injection control unit at the right side.

I do hope these 4 symptoms are somehow related to one another! Can somebody help me out on this one??

Thanks for your ideas/advice........

Rémy

420 SE (1989) 310000 kms
Reply to
"Rémy K."
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Uneven idle and hesitation upon acceleration suggest a vacuum leak. Air, unmetered by the fuel injection, may be leaking into the intake manifold causing the engine to run too lean. The engine tries to offset such a leak and that's the reason for the oscillating idle speed.

A vacuum leak may be as simple as a loose or cracked vacuum hose or more difficult as a leaking intake manifold gasket - those are found by applying some carburetor cleaner (fuel) to the suspected leak - it gets sucked into the engine and defacto corrects the lean mixture smoothing out the idle. Be CAREFUL if you do this for it can flash - right into your face!

Can't help you identify the "beeper."

Reply to
T.G. Lambach

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