# Engine Idle "Hunting" - RPMs waver at idle on 1988 D21 P/U with Z-24 Engine



## marc780 (Sep 6, 2007)

My 1988 D21 pickup with Z24 engine and 290,000 miles - runs strong when it is moving, but at idle, especially when warm, the idle is uneven. 

The engine is on its second valve job and has had new rings (10,000 miles ago), always passes smog, run strong, but i have had this problem for the last 10 years - uneven idling. Compression is strong like new, spark plugs are new, timing chain and gears are new, catalytic convertor is near new; alternator puts out a steady 14 volts - 
anybody know what it might be thats causing the surging idle? I have checked for vacuum leaks and the timing was reset to pass smog...anybody have any ideas?


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## marc780 (Sep 6, 2007)

Anybody? 
Could cleaning the EGR help this? I stck my finger under the EGR and pushed and it made the idle stumble - so i know it is working - could it just be clogged? I have read other people have successfully cleaned the EGR and not had to replace it - whats the best way, what product to use?


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