Hello all! New poster but have been using these forums for diagnosing and general help since I've bought my 2001 V70 XC 2.4t back in September!! This is such a helpful site ! I've named my Volvo Jerome and I love him so much but he has needed some work I tell you what. He was sitting for a long time before I bought him.

But another issue has yet arisen. Ever since I bought him at stop lights he would rev a little, and idles were a little rough. I hopes replacing the thermostat would help since it was JUNK, alas it did not. Its been about a month and yesterday he started idling really rough. He then popped up 3 codes, a P0304 cyl 4 misfire, P1237 which I see could be the boost pressure solenoid, but also p1357 which I dont see info on. Anything helps!!! Ty!!!

 

Update,

Did some basic fixes, got a new turbocharger boost solenoid on there, and threw some new spark plugs on. This car is brittle! What I thought was a small leak from the oil cap was a really bad one and has infiltrated the ignition coil area and has corroded and damaged the wires which I think is the mysterious P1357 code. Code P1237 went away as soon as a new TBS was put in. Cyl 4 is still misfiring but it needs a new coil pack for sure but I just need to save up and replace them all obvs. Idling is considerably better, but engine shake and noise is still there.