s14 sr missing badly-need help

[dreadedboost]

I have had my sr installed for about a month now and ever since its had a missing problem. when i drive it normally it seems to be happening at no specific rpm-but it does happen when it gets under partial load and if I give it more gas as it happens it goes away and pulls smoothly. another thing is that it happens pretty regularly at around 4500-5000 rpm when under full throttle and wont go past that because of how bad its missing. anybody have any ideas?

[9240sx]

sounds like a boost leak.Id check all the intercooler pipes.and vaccum lines.

[dreadedboost]

hmm i thought the same until i checked everything today and nothing is loose

[Silvia007]

bad mafs? My buddies S13 SR does exactly that. We went from Z32 to SOHC, nothing, so we got pissed... ordered the original SR mafs, still doing the same crap. What we did then was extend and sheild the signal wire and tap it into the ECU's mafs signal wire, ground the ground wire, and connect the positive wire to a switched 12volt source, seems to get rid of all the missing.

[dreadedboost]

so u pretty much redid the maf wiring? i grounded my shielding, but i dont see why you did all the other stuff, can you explain why maybe

[Silvia007]

Well the reason why we did what we did is because no matter what mafs we use, it would miss regardless. Almost at any throttle position, as long as you give it gas, it'll miss, backfire, whatever, barely driveable. We've used Z32, DOHC, SOHC, SR20DE, mafs to no avail, even the new SR20DET mafs we bought. So we decided to just redo the wiring for the mafs and it seems to work pretty well.

My 2 cents for ya.