Frankenstiein_B20

well my car feels like it hesitates. its been getting worse since i bought the car about a month and half ago. it will have its moments where it will idle really low and just shake the whole car and sound like a subaru almost. i have 90k miles on an 03. friends dad has a shop and told me it could possibly be the coil packs are going bad. that they usually go bad around 100k but maybe my car has just been ragged out. please help

zeroptzero

technically there isn't a difference between 90k or 100k miles, it's not like a switch where they fail at an exact mileage. As you approach 100k miles you should expect some or all of the coil packs to fail, so you are a good candidate for some bad coilpacks. The Subaru sound you mention indicates one cylinder that is not getting proper spark or fuel. The idle issues could be a map going bad or the Idle air control valve. Do a search on bad coilpacks and injectors and map sensor, idle valve to figure out how to diagnose the problems. These are all common problems people have posted on here.

Frankenstiein_B20

alrite thanks. im gonna switch coilpacks with a friend and slowly start marking possiblities off the check list

Frankenstiein_B20

by any chance it wouldnt throw a CEL would it

zeroptzero

actually yes , a misfire from a bad coil or injector would throw a cel and would tell you what cylinder it is. If you don't have a cel then it is most likely a map sensor issue, combined with a dirty idle control valve.

Mister Jew

just run the car and remove each coil pack one by one too see if the idle changes.....if the idle doesnt change that coil pack is bad.

Frankenstiein_B20

changed MAP and same thing so im definetly thinking the coil pack is going bad

ronnuke

Similar thing happened to me, but it was the spark plug gaps had opened too wide due to overheating causing the electrode to soften and open the gap over time. Replaced spark plugs with new properly gapped plugs and problems disappeared. HTH

Frankenstiein_B20

ya i checked the gap already and they r good. i was thinking it was plugs aswell so i changed them but it kept doing it

rudeboy1313

could it be fuel also. Do we have a fuel filter? or Maybe fuel pressure. 100k im sure we have some junk in those lines and injectors. Can be many factors. Guess go down the line.