Re: slight idle problem and acceleration noise

["basfe25" <drrub46@xxxx>]

This is a shot in the dark but usually a metallic rattle or high 
pitch rattle on acceleration is usually ( like I said usually not 
100%) the catalytic convertor. The honey comb inside breaks apart 
and then rattles away in there at higher speeds when there is a high 
force of exhaust passing through it. Also you might want to check to 
make sure all the bolts are on the metal heat shields that are ontop 
of the crossover pipes. They are mounted directly onto the pipe and 
if a bolt rusts off or falls out then that shield will rattle.
Another noise maker that will sound like "wooshing air" would be 
the alternator as it's going bad. It will have a high pitch sound to 
it and sorta sound like a whistle and turn into a grinding noise due 
to the bearings going on it. Have someone rev the engine while in 
neutral and the parking brakes on while your listening in the engine 
compartment. Pay attention around the alternator and work your way 
around. 

Steve

--- 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]