PO305- cylinder 5 misfire

Post by **jblackburn** » 23 Jan 2012, 12:06

http://www.fcpgroton.com/product-exec/p ... k+Plug+Set

$50. Totally overpriced if you ask me, but then my car is stock at 10 psi and I'm not sure how it would act with more power.

The coppers are $1.50 each and last ~30,000 miles before I go about changing them. I just don't really see the point for myself in throwing 10x that at spark plugs.

Cylinders are 1-5 across from the passenger side of the car.

s70glt novice[Will] · Post by **s70glt novice[Will]** » 23 Jan 2012, 12:10

Geez, that is a lot! Think the Bosch Super coppers would be okay? Worse comes to worse i wasted $10 and just switch them out.

Thanks for the info and help!

Post by **jblackburn** » 23 Jan 2012, 12:16

Worth a shot - it's less than the cost of 3 gallons of gas. I push my car pretty hard sometimes and I've had no problems. I took them out after 20,000 miles when I changed the timing belt, and they were barely worn at all.

I used to have Autolite Double Platinums, and while they ran OK (and got slightly better gas mileage - no lie - don't know why that is), it felt like my transmission was dying with the shift from 1st-2nd when it's at full power. When I switched back to the coppers, I found out it was definitely a misfire causing the jolt when it let off to change gears. Can't imagine it was good for the engine.

s70glt novice[Will] · Post by **s70glt novice[Will]** » 23 Jan 2012, 13:25

yea, seems i have a really bad one of those. i went down to the autoparts store and got some bosch super plus coppers with yttrium. It was the only coppers they had. hope they work
(for those who dont know, yttrium is a transitional metal thats chemically closer to the lanthanides)

Post by **jblackburn** » 23 Jan 2012, 13:26

Think that's what I have.

Set the gap closer to .026" rather than .028"...should help with the elevated boost pressure.

s70glt novice[Will] · Post by **s70glt novice[Will]** » 23 Jan 2012, 14:05

thats what im thinking. thanks for the help. maybe rename the title to make it a little more specific in case anyone else has these troubles

Roadrunner · Post by **Roadrunner** » 23 Jan 2012, 17:13

Late input but have you tried Denso U grove copper plugs? I use them and I am very pleased with them. For the spark plug wires get the lest rezentest (sp) type of good quilty. An OEM cap and rotor and use electricc greass to keep the corosion out of the plug wires connection. I am not sure about the HD coil for my car has the stock coil on it. Also check if their is a air leak in your intake tub from the air filter. This will cause the Air mass not to be reading right. Also if need be turn the distrubeter cap a small degree to increase RPM and this will end your miss.

s70glt novice[Will] · Post by **s70glt novice[Will]** » 23 Jan 2012, 20:44

I think its my wires. the date said 97 36 D:

With the new plugs its not as bad, but it still happens. I'll try and order the new wires from FCP Groton soon.

Thanks for the input roadrunner, i saw those on the screen, but went with the boschs, mine do have a U grove in the rod.

s70glt novice[Will] · Post by **s70glt novice[Will]** » 24 Jan 2012, 12:55

I gapped the new plugs to .25

I'll get a new gapper and gap to .025
still runs great though. Volvo's are tough

Post by **jblackburn** » 24 Jan 2012, 13:01

.25"?!? I'm surprised it's not running like a tractor.

PO305- cylinder 5 misfire

Re: PO305- cylinder 5 misfire