29 replies to this topic

[Domo]

I have a 98 v70 xc with a 16t, white injectors, t5 ecu I changed the front oxygen sensor today and on the way home, under full throttle I get a p0302 code, only in boost

Any ideas?

[Snabb T5M]

Well that's a misfire code on #2 cylinder. Pull the plugs and check the gaps. Should be between .0028 -.0026. How old are the plugs and are they coppers?

I have a 98 v70 xc with a 16t, white injectors, t5 ecu I changed the front oxygen sensor today and on the way home, under full throttle I get a p0302 code, only in boost

Any ideas?

[Domo]

The plugs are, new I will double check the gap

They are bosch platinum

[TRACStar]

They are bosch platinum

That could be your problem right there. My car ran like shit on platinum plugs.

Just go with coppers.

[Snabb T5M]

yea, disregard what all the ads are trying to sell you on, stick with a copper plug in a Volvo turbo car and be worry free.

That could be your problem right there. My car ran like shit on platinum plugs.

Just go with coppers.

[Domo]

So go with volvo blue box part?

[Commander Riker]

Either Volvo plugs or cheap coppers. You'll be shocked how much better the cheap aftermarket copper plugs will perform over the expensive aftermarket platinums.

[Snabb T5M]

Yea, I run either the Bosch Super Plus copper plugs for my T5, or NGK BKR7E or 6E plugs depending on what heat range I want.

Either Volvo plugs or cheap coppers. You'll be shocked how much better the cheap aftermarket copper plugs will perform over the expensive aftermarket platinums.

[Yea-but...]

Yea, I run either the Bosch Super Plus copper plugs for my T5, or NGK BKR7E or 6E plugs depending on what heat range I want.

Could you go into more detail with the heat range thing? Are you talking about combustion temps? how does it affect performace and gas mileage?

Thanks!

[Domo]

I will buy some cheap copper plugs today and try them.

[Snabb T5M]

Follow this link for a good discussion. In summary, I run the colder NGK plug (7E) in the summer time when the temps are higher just to prevent an additional source of heat that might pre-ignite the fuel mixture. The NGK 6E is the factory heat range plug and I run the factory heat range plug when the temps are colder. It shouldn't affect gas mileage, but like I said, with a colder plug it should prevent being a cause of a misfire with the mixture pre-igniting, so overall performance should go up since the engine is not misfiring and timing then being pulled.

However, if you are running stock boost levels (I'm not), then the OEM heat range plug should be fine. I experimented with the heat ranges and found my car works pretty well with a colder plug in the summer time. I gave a set of the colder plugs to my buddy (Korruption) who is running a 98 V70R and he too benefited from the colder plugs, or at least no longer gets misfire codes (he has been plagued with them).

http://www.ngksparkp...p2.asp?mode=nml

Could you go into more detail with the heat range thing? Are you talking about combustion temps? how does it affect performace and gas mileage?

Thanks!

[atefitty]

That could be your problem right there. My car ran like stuff on platinum plugs.

Just go with coppers.

What he said..Or go with OEM

[sconeman]

I agree with the 7e's in the summer. Not the best in the winter but I've used them then also. Can't go wrong with some coppers though. and +1 again make sure the gap isnt' too big.

[Yea-but...]

Follow this link for a good discussion. In summary, I run the colder NGK plug (7E) in the summer time when the temps are higher just to prevent an additional source of heat that might pre-ignite the fuel mixture. The NGK 6E is the factory heat range plug and I run the factory heat range plug when the temps are colder. It shouldn't affect gas mileage, but like I said, with a colder plug it should prevent being a cause of a misfire with the mixture pre-igniting, so overall performance should go up since the engine is not misfiring and timing then being pulled.

However, if you are running stock boost levels (I'm not), then the OEM heat range plug should be fine. I experimented with the heat ranges and found my car works pretty well with a colder plug in the summer time. I gave a set of the colder plugs to my buddy (Korruption) who is running a 98 V70R and he too benefited from the colder plugs, or at least no longer gets misfire codes (he has been plagued with them).

http://www.ngksparkp...p2.asp?mode=nml

I'm not running anywhere close to stock. Thanks for the info, in hot california, i should get a gain out of these. (Also im gapped to .023 soooooo)

[Snabb T5M]

What boost level you running on the 16T? 15psi is about the effective limit for a 16T. And .0023??? don't need to go that small. I think the smallest most people run is .0026.

I'm not running anywhere close to stock. Thanks for the info, in hot california, i should get a gain out of these. (Also im gapped to .023 soooooo)

[Yea-but...]

What boost level you running on the 16T? 15psi is about the effective limit for a 16T. And .0023??? don't need to go that small. I think the smallest most people run is .0026.

17 psi on ard green. And i know, but on the crap gapper i had it was the best choice. I'll try it differently with my new plugs. And i thought .0026 was too big for 17psi?

BTW, i'm assuming spark plug gap has a direct influence on mileage and performance? So running wider gaps would help me with both?

[Snabb T5M]

I'm running .0026 at 18.5psi with no CELs.

17 psi on ard green. And i know, but on the crap gapper i had it was the best choice. I'll try it differently with my new plugs. And i thought .0026 was too big for 17psi?

[scumcity14]

What boost level you running on the 16T? 15psi is about the effective limit for a 16T. And .0023??? don't need to go that small. I think the smallest most people run is .0026.

Lee, that gap seems awful small! ( too many zeros..) I run champions at .026 on a 16t @~15-16psi and my car doesn't disapoint...but I get misfires as the plugs wear(@15k the gap gets to ~.031+) so I re-gap every oil change and change them at every 3rd.

Edited by scumcity14, 10 June 2012 - 08:35 PM.

[Snabb T5M]

Doh!!! My math isn't the greatest. Maybe it is .026.

Lee, that gap seems awful small! ( too many zeros..) I run champions at .026 on a 16t @~15-16psi and my car doesn't disapoint...but I get misfires as the plugs wear(@15k the gap gets to ~.031+) so I re-gap every oil change and change them at every 3rd.

[Yea-but...]

I thought it was .02 intstead of .002 but its been awhile since i looked .

Anyway, i'll get new plugs and gap them correctly. Thanks. Sorry for thread jacking