Well for the last month or more I have been getting a surging idle... opti about 1 yr. old. plugs,wires,lifters,pcv. only a week old. 02's only 5 months old. on my scanner they seem to be switching fine. new coil. can't figure it out. fluctuates about 100-150 rpm's. when cold or warm sitting in park at idle. I have the usual cam surge at lower rpm's when cruising. but this idle surging deal is throwing me for a loop? seems to do it about every 3-5 seconds. car is running strong not breaking up. shows alittle rich at idle on my scanner, but I think that is from overlap from the cam. when I pulled out the plugs they were not black at all. all 8 if anything were alittle white. not really even beige. so maybe alittle lean... but I can't find anything else wrong. not throwing any codes.... walbro 255 fp. kirbin afpr. elec. fp gauge, is not dropping even when surging. fuel filter about 6 months old... any ideas???

 

Have you changed your IAC?

 

No I haven't, I think it's original. I notice on my scanner, it is jumping around alittle...maybe I should replace it..thanks.

 

deff cheak ur IAC....it just might be dirty and have some carbon build up on it...