Buick 1000 rpm idle

Hi all
My otherwise well-behaving -95 Riviera 3800SC keeps its idle steadily on 1000 rpm, why does it do that? I've checked the IAC and it seems to be
within limits. Any suggestions anybody?
Kent
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It could be a vacuum leak.
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Does engine idle at 1000 rpm as soon as the engine is started or it move from lower RPM to ~ 1000 rpm after after a short driving distrance or engine idling? If the ECU can not read throttle position unit correctly, the ECU will lock to higher RPM such as 1000 or 1200 rpm. Typically the engine should idle around 600 to 800 max. If the condition above describe your problem than you should have the throttle position unit replace. The throttle position unit locates on the throttle body assembly below throttle linkage shaft. It main purpose is to record and report to ECU the shaft rotation angle (basically your gas pedal position as you press on the pedal). You may have to remove the throttle unit from the intake housing in order to access this unit. It is a simple job using simple tools. Hope this help! MN -- Commercial email is not welcome. For your own information only. No warranty of any kind is provided with this message

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It goes right up to 1000 and stays there steady as a rock, no fluctuation at all. I'll check the TPS right away. I suppose that a vacuum leak would make the idle more irregular - at least occasionally. I know there should be a tech bulletin about high idle speed on the -95 Riv, but I've never seen it.
Thanks guys Kent

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