To get the motor to idle smooth all 6 cylinders must be within 5% of each other in all respects. All of the fuel injectors must have perfect patterns and similar pressures, all spark plugs gapped and in good shape, all ignition wiring in top shape, all cylinder pressures within 5% and so on. If you have 1 cylinder out a little the idle drops and then the idle motor tries to compensate. By time the correction kicks in you are on the better cylinders so you overshoot because the correction was too late so now the idle motor tries to slow the motor down and now you have the hunting you notice. Start by checking the cylinder pressures. If they aren't within 5% nothing will help. If they are close have the fuel injectors checked and cleaned on an injector tester. Properly set up the engine can be "super smooth". For the noise you hear check the idler bearings for the fan belt, they get noisy before they fail. Very common for Deloreans to have the idle improperly set up, most mechanics don't understand the system so they try to "fix" things by turning adjustments. David Teitelbaum vin 10757 --- In dmcnews@xxxx, Soma576@xxxx wrote: > Hey all, > > thanks to Gary (checksix), i was able to find the problem with my idle not > kicking down. my throttle was incorrectly adjusted ever since i bought the > car in 2000!! well it kicks down like it should, in fact, the car seems to > have a lot more kick now than it used to! i love it! > > my only complaint is that the idle is a little random at idle speed. the > needle seems to hover around 750 or so, and it moves around all over the > place randomly from about 450 to almost 1000, then it goes back to 750 for a > bit, then dances, then back to 750. i know the engine isn't supposed to be > super smooth, but seems a little excessive. what can i do to smoothen things > out? i know my engine CAN be better because it used to be until i adjusted > everything over again. sometimes it is so erratic my oil pressure never > drops to 40 like it usually does at idle speed. > > also, i've had this problem for a while too - on accelerating in any gear in > any manner, i hear a noisy vibration sound from the engine between about 2500 > to 2900 RPM. you can go slow and it starts, or you can go fast, it's there. > it's quite high frequency, sounds metallic. it used to sound like air > whooshing in an odd way, but lately it's sounded abrasive. it will do this > upon deceleration too, but it doesn't sound as loud. > > any idea what this could be? > > Andy > > Soma576@xxxx > 1982 DeLorean DMC-12 VIN#11596 > Fargo, ND 58102 > > > [Non-text portions of this message have been removed]