i have an 05 xb with auto and at 25000 miles i got a ruff idle in drive at a stop light.jada jada jad... same stuff that has been posted before. so i read on grounding wires (looks to messy under the hood), and spark plugs (and the gap) and resetting the ecu for the cai and exhaust. so i went and bought the best plug they carried (bosh platium infusium with uranium for 45.00). and took out the ecu fuse while i did the work. Took about 25 min (would have been faster if not for the stupid strut bar) and put the fuse back in and ran it around the block. it did have a noticablly smoother acc. through the rpm range. got it home when it was warm and put the ac on and... it still vibrates . oh well it was worth a try. also i see posts where the gap should be 32 well these plus have 4 probes and are not adjustible. also the computer at the parts store said the regular ones need to be gaped at 44. some someone is wrong. thought id let everyone know my experience.

 

bosch plugs break. the insulator and the actual electrode will come apart and ruin the drivability of your car

 

I bought cheap bosch plugs. Single electrode. Platinum Plus. $2.49 a plug and they are just fine. I bought the Platinum Infusion's first and hated them. I lost gas millage. I sent them back to Bosch for a refund.

 

I used to run bosch plats in my old monte carlo, never had one problem, I know vw owners who run bosch also, no problems. Where did you get your info?

 

How hard is it to change the plugs on our boxes?

 

not hard at all (with no strut bar) just remove the black plastic engine cover and the 4 coil pack-spark plug-combo-thinges are right there. 1 10 mm screw holds the coil down then just pop it off and take out the spark plug. then put it back together. i do 1 at a time so not to put the wrong coil back on.

 

Cool... thanks

 

if you run single electrode bosche or any non platinum bosch theyre fine. the multi tip ones and platinum ones have problems



where do I get my info? in this situation first hand experience in four different cars.

 

I'm just cheap,I have been running Champion Copper Plus for 20K between changes without any problems.No noticible difference from stock. Gapped at .44.

Scott

 

never had any luck with the bosch, ive seen more driveability issues after people put them in, replace them with something else like NGK and its fine again

 

Here is what I can't figure out. What is the gap supposed to be? Some say .44 others say .32! I wish I knew the answer. I could car less about what plug. I just wanna know what the true gap is supposed to be.

 

doesnt matter because you shouldnt gap a platnum plug or the irridums.

 

I asked the question in general. I have worked on cars most of my life. Every application is different.

 

yes but for the most part the platnums come pregaped and shouldnt be changed so you dont cause damage to the tip

 

The only way you can damage the tip is if you beat on it with something. Or use a screw driver to pry it open. I am looking for feed back on what the gap is supposed to be. Not the in's and out's of a spark plug. I know very well what a spark plug can do and it can't. We run Autolite's in our race motors. I think they suck for street applications. But they can't be beat in our races motors. All I am looking for is what the gap is supposed to be for a spark plug for a scion XB.

 

go with 32mm the owners manual says 31

 

so why does advanced auto and auto zone say 44 in the computer?

 

bighvyxb---- that's what I was trying to figure out. I gapped mine at .32 like the stock plugs that came out were. I was just looking for some useful info on what it's really supposed to be.

 

Heres the fact jack!
For that kind of coinage you should have gotten the NGK Irridiums, Bosch anything sucks anymore. They get gapped at .044 (gotta be VERY carefull with the fragile tip tho). You get a more efficient spark and better performance, more MPGs and smoother idle.
I added these just before I took a 1500 mile roadtrip and my mpgs. went up by 3 and the engine ran smoother than it did the day I brought it home.