fouling spark plugs????
 

ok so i am having some trouble with my spark plugs. I just replaced my spark plugs about 3 weeks ago (about 600 miles) . I put the factory sparks plugs NGK BUR7EQP, BUR9EQP leading and trailing. I haven't pulled them out yet but the car is performing as when they were fouled last time. (around 5000rpm in 3gear they sputter)

Should i used different plugs? should i put all leading or all trailing plugs? could i have a problem with my engine? (maybe oil is getting to the plugs)

any help

I seem to have the same problem as you, my car was idling pretty bad so I replaced the plugs, and it worked fine, then it came back. I havent had time to figure out though what it could be because some other things took priority.

spark plugs
 

I had some issues like you 2,I found that with my map on the apexi, that when cold it was pumping a little to much fuel in,I have to use HKS plugs.and it runs fine.

which hks plugs?

hks plugs
 

Hks superfire racing plugs.you need to know your level of tune when buying

level of tune? which hks spark plug are compatible with the ngk rx7 plugs?

IF the stock plugs foul fast, you have to look at your driving habits and/or mods.

Also, i would check in the tune, people usually neglect that because they assume that doesnt make a difference.

I use the stock 7 and 9s and i change them once a year. Each year for the past 4 years they always looked the same, i even posted a thread about them and was told that my plugs looked normal.

plugs
 

I have an apexi ecu n the car is mapped,The hks plugs give you a stronger spark helping to burn the fuel better than standard plugs, and they dont bow out under boost.The best thing to try is run all 9's leading and trailing and red line the car occasionaly that does help fouling,Get the car mapped.what type of oil you use makes a differance as well.there are lots of factors.Im running GTX 10/40 standard oil.

I think my stock system would always break up at 10 psi and above before I installed a HKS Twin Power.

See if you can borrow a friend's unit to try it out.If they have the harness it is just a quick plug-in.

Barry

If you are having breakup at higher rpm's on a stock setup, maybe something is wrong with your ignition.

If you have a PFC, maybe you need a tune.

i have a power fc, walbro pump,downpipe, catback, intake etc.........pushing 300whp@14psi. i just replaced my fuel filter, which was in pretty bad shape. could i have some excess fuel now? i haven't retune. i going to do a full rebuild with mazdatrix streetport and going to retune. also planning to use all 9 spark plugs. if this doesn't work i will buy the hks plugs. yeah

Wait why are you rebuilding? Did you compression test your engine?