98 Outback shaking and chk engine light

[awick]

We just bought a green '98 Subaru legacy outback wagon a week ago from a fellow that is a mechanic at an automotive garage about 90 miles away from us. We noticed the day after we bought it that it started to shake alot when you were stopped and at idle, later that same day the check engine light came on. I called the guy we bought it from (less than 24 hours before) and told him the problems we were having and he told me I could bring it back down to him and he would check it out at his shop. I asked him if he ever noticed any shaking or shuddering while he was driving it (he had been driving it for the past few months) and he said he hadn't, he also told me that he had replaced all kinds of things on the Subaru, the belts, the different fluids, etc. so he couldn't believe it was already having a problem. That monday I drove down there, he hooked it up to the diagnostic machine and said that it was reading PO302 and PO304 (cylinders misfiring). He said he would take them out and look at them but said they shouldn't be having a problem. I waited with my five year old for two hours, he brought the car down to a park behind his shop, said he didn't see anything wrong with the cylinders and that the check engine light was now off so it was fixed. I drove it home, realizing when I stopped that the subaru was still shaking (maybe a little bit less), but still shaking. I thought maybe we could live with this but then the check engine light came back on four days ago, it still shakes when stopped, but is pretty smooth when you are moving and accelerating, is this something we should be concerned with, some of the posts say it is normal to have a shake? Or should we return it to the "mechanic" that sold us our green lemon?

[lmdew]

The mis fire could be caused by bad gas, poor fuel injectors, plug wires....

Since its cyclinders 2&4 I would not think it was a coil.

 

You could try some gas treatment for water removal and injector cleaner. I would have a good Mechanic look at the plugs, time consuming on this engine. An exhaust gas test would also tell you if things were missing.

 

You could start the car in a dark place and mist the plug wires with water spray, if you see sparks, replace the wires.

 

Just because the CEL went out does not mean all the problems are gone. Some codes take a while to set again.

 

Good Luck