sputters at WOT

[kneipperk]

so i no longer think my prob has anything to do with me replacing my tb shaft seals. NO BOOST LEAK AT ALL. I changed ngk plugs and it seemed to give me a little bit more power but it still jerks and seems like my car misfire at WOT. I can build boost up to 14psi as long as i only give it a little throttle, but when i go WOT it studders and spudders and jerks around like crazy. the new plugs just gave it more power and made it jerk even harder! i was thinking about testing my coil. my plug wires look to be ok but is there a way to test them? it almost seems like more a cylinder misfire then fuel cut but im not sure. how can i diagnos my car? if my problem isnt spark then should i start checkin fuel system? I have a box of parts including walbro 255 pump i want to throw in but i would wrather figure out my problems first
my buddy took his 1st gen to a shop because it was running like crap and they diagnos it as bad injector, he picked it up and brought it to me, i put new injectors in and clean his fuel rail and his problem is solved , wish i know how they diagnosed it. i have had 4 dsm's over the course of the last 5 years and have been able to fix every problem i have every come across (and i have had some pretty nasty problems) how can i diagnose my prob?????? Thanks in advance for any help, you guys are awesome!

 

[viprez586]

Spark plug gap? Go -.028"
When were the spark plug wires replaced? They might be arc-ing.

If you have the stock plastic BOV it could be leaking. Try turning down the boost to stock to help diagnose your problem.

 

[kneipperk]

i got the car about a month ago, only has a lightweight flywheel and exedy clutch and for some reason it always boosted 14psi then it drops to about 12psi. but i have it at stock. and got evo8 plastic bov. still plastic but seems to hold pressure a lot better than stock. it ran perfect for a few weeks then it just started jerkin and spudderin. would the IAC or TPS make this big of effect or just make it idle rough? i did the tb shaft seals and marked the tps in like 6 different spots so i know when i put it back together it is in the same spot. the car has always thrown code p0505 idle system malfunction but it ran pretty good for a few weeks.

 

[HurleyTSi]

The stock Evo 8 BOV is garbage too. Hence why it's one of the first things Evo guys replace just like 2g owners.

The jerking issue is most likely related to spark. Try gapping your plugs a little tighter. NGKs usually come at 28. If that doesn't help change the wires.

If your car had a fuel issue it would most likely throw a fuel trim code. Speaking of which....do you have any CELs?

 

[kneipperk]

ever since i got the car it has put out "p0505 idle control system malfunction" figured it was probobly the tps or the iac. biss oring and shaft seals were leaking but since i fixed that i have had no leaks. and i checked for any new codes the other day but it still only has the 1 code p0505

oh and yeah i figured any plastic bov is junk but i just thought i would atleast hold a few psi. but i have a blitz bov but i dont have uic pipe for it to mount to. anybody got a good cheap set up for 2g piping?

 

[MIenKEi446]

Check gapping, or the ignition wires.

 

[rocafellafw]

I had the same issue, I would build boost fine but if I went WOT the car would jerk, sputter, and hesitate. Turned out the wire got ripped out of the knock sensor while doing the motor mounts. The ECU was pulling timing since it could not detect knock, it felt just like misire, boost leaks and fuel cut. Test your knock sensor just to be sure it's not dead

 

[idkiliketurbos]

Also something that I dont think anybody posted yet was maybe a bad coil pack? I've heard of people with a similar sounding problem and that was their answer.

 

[kneipperk]

well my problem is no more, i put the correct ngk plugs in (the dumbass at pepboys didnt believe me that they were the wrong plugs) and i adjusted my TPS sensor and i have full power back with no jerking or sputtering.... so if anybody goes to pepboys and needs spark plugs for a 2g they have the wrong number in the computer and all it shows up with is the non-turbo plugs eventhough they are looking up TSI. just order them for a 1g. i knew it was ignition/spark problem. i read a million threads about it and almost all of them turned out to be spark so i thought i would double check mine.... Thanks again for everybodys input and for all the threads already posted!!!!!!!!

 

[sighless]

whats the correct plugs?

 

[DSMDriver69]

im having the exact same problem, but i think my is just a boost leak.

 

[sighless]

i fixed mine with a fuel pump re-wire.

 

[Cyboula]

whats the correct plugs?

use to be NGK BPR6ES, but i recommend Iridium BPR7EIX

 

[AndrewD5418]

use to be NGK BPR6ES, but i recommend Iridium BPR7EIX

You fail miserably for even suggesting iridium. NGK REGULAR COPPER ONLY.

 

[Cyboula]

You fail miserably for even suggesting iridium. NGK REGULAR COPPER ONLY.

Sry...

 

[AndrewD5418]

Sry...

Sorry if I sounded rude in my comment; but I just wanted to make it clear to use those and those only.

 

[supravw]

Sorry if I sounded rude in my comment; but I just wanted to make it clear to use those and those only.

I run iridium plugs in both of my 4g63s. Evo's come stock with them, there's nothing wrong with running iridium in a dsm. I know plenty of guys who run them.