850 T-5 Spark plug confusion

norfolkpauly · Post by **norfolkpauly** » 29 Dec 2010, 13:54

Hi All

Since I took care of my misfire issues, and had a standard exhaust fitted, I have noticed a strange vibration through the dashboard area that wasn't there before. As if the motor is running slightly lumpy, especially noticeable when accelerating from standstill.

My question is this... I replaced my spark plugs 2-3 weeks ago with what my local motoring factor recommended, Bosch super plus, part no. FGR 7 DQE+. These have four electrodes instead of the usual one, and they aren't gap-adjustable, they're pre-set at 1.35mm (or 0.053 inch). All the threads I've read on this site state a gap of 0.028 inch/ How can this be???!!!

Also my fuel consumption doesn't seem what it should, averaging between 20 and 20.7 at the most.

reds70turbo · Post by **reds70turbo** » 29 Dec 2010, 19:32

For your motor you want the single electrode plugs. Also be sure to check the gap before installing.

Some use Bosch/Champion Copper plugs, although they do not have a very long life span.

I'm a fan of Volvo plugs, I run a .025 gap to satisfy my ST ECU remap. I changed my last set of Volvo plugs after about 30K miles and they were still very nice looking. I probably could've gotten another 10K or so out of them but they were out and I had the new ones so in the new went.