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4000rpm+ Splattering

jap33

By jap33,
in General Maintenance

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jap33 Explorer

jap33

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when my 33 was hitting full boost whether it was stock boost or 12psi, it was splattering and backfiring. after reading alot of posts on the same issue, most people said to change the spark plugs and the sparkplug gap.

I bought new spark plugs for the car and it was still the same, if not worse. i then changes the gap from 1.1 to 0.85. it stopped most of the splattering but it was still doing it with the throttle fully opened, i then changed the gap from 0.85 to 0.7. still the same. i was talking to an engineer and he said the smaller the gap the faster it sparks, but the spark is not as powerfull. he said that my car was also running lean due to the build up on the sparkplugs. which then lead me to beleive that it was a fuel managment problem which could put a dent in my wallet. after thinking of what could be making the engine run lean, the cheapest possible thing to change was the fuel filter. after removing the fuel filter we found that it was quiet dirty and had alot of build up in it. he said this is why it was running lean. so after a new fuel filter was installed. the car runs perfect from 8psi to 15 psi. So if anyone seems to have this splattering problem instead of going straight out and upgrading the fuel managment check the fuel filter and spark plugs. this could save you $$$$

spark plugs: ngk = 6 x $4

fuel filter = 1 x $18

cheers, amd i hope this fixes your fuel problems.

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