I've been driving my 960 from Montana to California and back to Montana over the last week. In the last 10 days I've logged almost 2k, and about 3 days ago the car started to randomly idle and run like crap until about 2,500 RPM. I have no check engine light, and its only been happening sporadically. I can drive the car for anything between 10 minutes and 2 hrs and it will start acting up and then go away, only to return later. It also doesn't matter if I'm doing city or highway driving. I talked to a volvo mechanic and he suggested that I replace my NGK plugs that have about 20,000 miles on them with some Volvo ones. I know these engines are pretty picky, so maybe this will solve the problem?? Is there anything else I can do? I still have to drive about 1,200 more miles. Within the last few months I've replaced the MAF sensor and the Fuel filter. O2 sensor was replaced about 2 years ago.

 

Plugs may do it or you may also have a coil going bad.

 

I got the plugs, and while I was changing them out I noticed that one of the wires on my #2 coil was corroded and hanging on by a thread. The other was almost as bad. The weak one broke when I tried to pull the plug out. I'm going to assume this was causing my problem. Now I need to find new ends to solder on, and hopefully everything will be ok. Tech, I noticed on the coil there is a 15+ and a 1-. Is something disastrous going to happen if I mix up the wires when I put it all back together? I'm pretty sure the 15+ had the red/green wire plugged into it, and the 1- had the brown/beige wire plugged into it.

 

Compare the wires to the other coils.
If there is a Volvo dealer near you can buy repair wires that you can solder or crimp on the harness to fix it.

 

I went to radio shack and got some crimp connector ends. I modified them a little to make them fit the stock plug, and am going to put it back on tomorrow morning. Hopefully it'll work. As for the wires there is only one other red/green wire. All the others are different colors. If I hook them up wrong will the car just not run?

 

got it figured out and mcguivered it all back together. While I was in there I fixed a few of the other wires, and with the new volvo plugs it runs damn good! If anyone else has this problem I'll take a few pictures that show how I was able to rebuild the plug better than stock.

 

Good Deal!!!

 

when all was said and done I drove an official 2,983.1 miles over a period of 11 days. For about 50 of those miles I had a little trouble (broken wire, and rough idle) but after I did my repairs I did about 1,000 miles that were totally trouble free. Volvo's rock!

 

Awsome!