I may be beating a dead and buried horse, but there seems to be some debate about these plugs and I wanted to add my experience.
96 Cabrio, VIN B ABA (OBD2), I put in bosch platinum +4s at 102k miles when I got the car along with new O2 sensors, cap, rotor and wires. Car seemed to run ok, mileage was a little low 21-22 mpg. After about 4k miles I started getting a CEL and the codes were catalyst effeciency below threshold and intermittent random misfires. Car still pulled ok and didn't miss under load, idle hunted a little bit but I've seen worse. I thought it might have been a couple of tanks of bad gas so I ran about 3 tanks worth of Techron through it. I would clear the CEL but it would come back within a couple of days. Finally earlier this week I got the dreaded flashing CEL for about 10 seconds on the way to work, then a steady CEL. Pulled the codes and I was getting misfires on 3 and 4 as well as random misfires.
Last night went to the zone and bought the $0.99 Bosch coppers and put them in. Idle seems steadier so far and no CEL. The block 110 misfire counts are way lower. The 5k mile +4s I pulled out looked a little more carboned up than I am used to and the gap seems way too big compared to what I put in. I think at least for the OBD2 ABAs, the +4s are not the way to go.
FWIW, the specified gap between the OBD1 and OBD2 ABAs is different, OBD1 wants .6mm (24/1000th") and OBD2 wants .7mm (32/1000th"). I guess the wider gap for OBD2 is probably for a hotter spark to keep the plugs clean.
YMMV,
Brian
96 Cabrio, VIN B ABA (OBD2), I put in bosch platinum +4s at 102k miles when I got the car along with new O2 sensors, cap, rotor and wires. Car seemed to run ok, mileage was a little low 21-22 mpg. After about 4k miles I started getting a CEL and the codes were catalyst effeciency below threshold and intermittent random misfires. Car still pulled ok and didn't miss under load, idle hunted a little bit but I've seen worse. I thought it might have been a couple of tanks of bad gas so I ran about 3 tanks worth of Techron through it. I would clear the CEL but it would come back within a couple of days. Finally earlier this week I got the dreaded flashing CEL for about 10 seconds on the way to work, then a steady CEL. Pulled the codes and I was getting misfires on 3 and 4 as well as random misfires.
Last night went to the zone and bought the $0.99 Bosch coppers and put them in. Idle seems steadier so far and no CEL. The block 110 misfire counts are way lower. The 5k mile +4s I pulled out looked a little more carboned up than I am used to and the gap seems way too big compared to what I put in. I think at least for the OBD2 ABAs, the +4s are not the way to go.
FWIW, the specified gap between the OBD1 and OBD2 ABAs is different, OBD1 wants .6mm (24/1000th") and OBD2 wants .7mm (32/1000th"). I guess the wider gap for OBD2 is probably for a hotter spark to keep the plugs clean.
YMMV,
Brian
