2G Dsm sounds like a wrx

[zotis777]

Hey I’m needing help with my dsm. I have a 98 gsx. I bought it kind of hacked, I’ve done a lot to it so far. Originally I picked it up with some pretty mean boost leak problems. Diy front mount was garbage.



It got a vrsf, 16g installed. Boost leak tested to 25psi. Fixed a couple couplers and a leaking BISS screw. I installed ECMlink. Oil and filter, filled it with fresh gas. New plugs and wires, my front o2 was reading 0.0v all the time and I replaced it. did all the usual stuff trying to freshen the car up.



Well after it sounded like a wrx, it idles fine but with an occasional little skip. Revs fine, but the moment there’s any load on the car it just skips and rubles. No CEL it would be nice if there was it could tell me what cylinder is misfiring. Well I’ve been trying to track that down for a month now. I’m on my 3rd set of plugs and wires, I cleaned the injectors and did filter baskets/injector seals/rail spacers/pintle caps. No luck, every time I take the plugs out they look dry fouled except that the electrode ground is white and charred. I don’t know what that means at all, despite tons of googling on reading plugs nobody’s described dry fouling with a white electrode ground. I’ve searched here and have not found a definitive answer. If the problem is simple and I’m just being a dummy and could’ve found it just by altering my keywords I apologize in advance, though I would welcome the fire just to get this car running top.


Currently no aftermarket monitoring, I’ve been looking at estimated AFRs and the other “estimates” that link can create, I doubt they’re accurate (one of my logs had an estimated 433hp so I know they’re not spot on) but at idle they’re consistently 12:1 area AFRs.



Finally compression tested it and got a solid 135 all across the board, that’s only 2psi above the service limit. That worries me but I don’t think it would cause the problems I’m experiencing. I’m not sure that compression tester was particularly accurate it’s a garage sale special that required some Teflon taping to get it to help pressure and every time I went ahead and tightened a fitting/sealed the tester better it read a little bit higher. Again I don’t think I trust the tester, if 135 is accurate (I hope it’s not) then wouldn’t it be idling and running far worse than what’s described?


I went to test coil pack and power transistor tonight only to find out the hard way that I’ve lent my multimeter to a friend, I will be testing those soon. I’m sorry for the long post but I’m running out of ideas, I’ve tried everything I can think of and I’ve yet to make it at all better or worse. Which seems to me to be pointing to the idea that I’m not getting warmer at all.


I have pictures of the plugs, logs, videos, whatever needed to help track this down. I’m ready to get this thing driving smoothly

 

[boostdawd]

The tps is real sensitive to changes. Tap it with a screwdriver little by little. U want to be at .63.

 

[zotis777]

tps at .63, i was trying to get airflowperev to sit on .25 and i couldnt, air leak? i had to take the rail off to change the coils. fuel trims all seem wonky and so does afrest. trying to figure out how to fix any of the above and get it running well. i think im going to boost leak test it again once the car cools off. literally sitting at the kitchen table sifting through my log typing this up. it sounded better at idle despite it being a little higher, it didnt seem to have the same skip at idle or occasional miss.


however the new coils ohmed within spec and - it still runs like hot garbage, im considering going out and getting a video of the car driving to show you guys the noise. it sounds like something is just off that im not getting and i am checking everything i can.

it wont even throw me a misfire code.


also conditions that should induce some form of knock and link still logs 0 no matter what, im assuming thats telltale faulty knock sensor? I'll be changing it but is there any way that could cause this misfire or skip or hesitation or whatever this demonic noise is my 4g63 is making?

 

[AWD-Tony]

To adjust airflowperrev, slide the 0 & 5hz up or down in MAF Comp. But I'd start with getting your idle correct first. Hope these help

You must be logged in to view this image or video.

You must be logged in to view this image or video.