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View Full Version : Lumpy idle/inconsistent oil press


kamechikara
11-08-2010, 03:41 PM
Hey got a question for you all to take a stab at...

I have a red top SR in my silvia. It's lightly built with boltons and the ecu was tuned at JWT then then dyno tuned at Z car garage. I has run great for years (knock on wood) but has always had a bit of a sketchy idle. I just hooked up and I can see that the pressure dips pretty low sometimes. More specifically:

Everything in gear is fine, boost, oil press, temps, etc...When I come out of gear and decelerate to a stop, the idle dips down really low at time and will occasionally cut out completely. I also now notice that the oil pressure will be at about 1 bar then dip below that slightly (75psi) when the idle is dipping. I have never been able to figure out what causes my idle to be irratic and am now wondering if it has to do with the oil pressure. Are the two things related, one causes the other, oil press just dips because the idle dips??after I give a few revs things will straighten back out and idle more smoothly (although its never totally smooth because I think the engine had cams in it when I got it from Japan...also never checked...lame I know).

The car drives great so I'm not concerned but I am curious if anyone has any ideas or similar experience. Thanks for reading and I hope for some wisdom.