NissanNismoZ

My manifolds were said to be warped, but I can't seem to find any leak coming out of them. But it is definitely leaking around the y-pipe area.

Have you checked your inhibitor relay? /clutch Neutral safety switch?

YES YES YES! Okay, so i was also advised to replace the TPS, as it has some say so in injector timing as well (and my tranny was shifting way too far down sometimes for no reason) anyway, and i replaced the fuel filter, so remember how before this, it was running too lean? Now its running too rich! Weird for me to be excited for, but FINALLY something says my injectors are fine. I pulled all my plugs and checked them all and they're all brown and smell like fuel. YES! So, another member advises me yet again, any leak before the O2 causes it to run rich. So i DO have another exhaust leak at the Y-pipe, again. Ill be getting it fixed and hopefully this fixes it!! I also put the timing back a tooth to where it was, and back to fully advanced at that level. Here's a pic of how the plugs looked: I also remade my acceleration video, and my 'problem' video. Acceleration: http://s208.photobucket.com/albums/bb9/Nismo_Nissan_350Z/?action=view&current=VID_20120825_164646.mp4 Problem: http://s208.photobucket.com/albums/bb9/Nismo_Nissan_350Z/?action=view&current=VID_20120825_164245.mp4

Question.. Is it possible to look at an injector and tell if it's dirty? Also.. I've been thinking about it.. Doesn't the floor of injectors run in a series.. Say how it starts in the flow at injector 5 and ends at 6..right? So if 5 is dirty.. Wouldn't thay block flow to the rest of the injectors? Just an idea.. Is there even like a pressurized can of something I can run the engine off of and clean them?? Maybe let it soak into the fuel rail? I really don't have the patience to remove the intake again.. So is that possible?? Thanks. I swear something has to change with it..

Just got a set of LE cloth seats.. I have to say just sitting in them compared to my XE seats they're definitely more comfy! Then again my XE seats were worn in (though cosmetically they look nice?) I could feel a bar when I leaned back into the seat.

Oh. Yeah I put it in and drive it hard until I was nearly out of gas.. That does make sense.. Thanks!

Alright ill do that! Should I put in a half tank, near empty or on a full tank?

I ran through one bottle.. But that was it, should I try more?

Hah yeah, it took seriously no longer than 3 mins to swap. I would have been stupid to not have tried a new one.. Wow! Thats about like the knock sensor on the VG30E. It sucks. Though now i can say i can rremove the upper and lower intakes and put them all back on in less than 2-3 hours...LOL. Now i just need to see what/which injectors are dirty..somehow...

Yes, yes you did! I knew someone did but forgot about it.. I used a purolator, didnt think one of those could vary too much since they're just a spring valve..right? or no?

Not trying to question you or anything, but how could i tell if i had a dirty injector? wouldnt it run with a slight miss?

I found out the PCV valve was only 4.99 so i couldnt resist and replaced it. I dont know if maybe the PCV was causing some sort of issue as well but it definitely helped in bottom end and it seemed to go up my hill in 2nd gear a little better instead of slowing down.. I swear every little thing ive done today has helped it, but its still not fixed. Once i find out this problem it should be fairly powerful!! The PCV valve was pretty stiff with sludge.. and yes, my fuel pressure regulator hose was unhooked for a while as well, but it was hooked back up a while back.. But thanks for the suggestion With the plugs reading lean last it has to be a fuel problem..or vacuum leak..but i can NOT find a single vacuum leak. Not one!! Are there any accessories that connect to the intake that may be dirty and sticking and causing a vacuum leak?

So today, i installed my new fuel filter, new MAF wires and known working MAF (as a test) and reset the computer during all that time of installing the new stuff, hooked it up and again, there was a slight increase in power, but its still not right. i did take an acceleration video if anyone wants to see it.. anyway. I let it idle around 30mins while just wiggling wires and vacuum hoses hoping for something to happen..but no change, but it reminded me, the one thing i havent checked/changed the PCV valve. I do remember it being dirty, but ignored it. Could it have an effect on performance? Thanks.

Yes, I did reset the ecu.. That was actually the first thing on my mind. Lol the cam timing is dead on, I can say that. But the distributor is a possibility. I mean what else can I blame at this point? Today after work I'll pull the dizzy and try turning the gear and seeing if it turns in sync with the rotor (right?) and I'm going to replace my fuel filter in the Bay.. If I had a timing light I'd definitely check it! Haha yeah no crap! I have replaced nearly every sensor besides the MAF and IACV. Whatever it is is seriously affecting how quickly the fuel catches up (an assumption because of how quick it revs when I slowly floor it.) but yet I can smell gas pretty strong after I floor it either way.. My guess now is a timing or fuel issue..

Maybe thats whats wrong with mine..with that done above ^ My idle is fixed and my WOT from idle is fixed, though it still revs up faster when given a light pedal, compared to flooring it, but its getting there. Im scared to advance it anymore, because i dont know if its already way too advanced or not..but I just dont know.. I do know my cam timing is right but..i just dont know what could be the problem anymore..it should have NOTHING to complain about.. i have zero vacuum leaks, zero exhaust leaks (so far...) and its getting plenty of air, plenty of spark, and fuel pressures are good and all injectors spray evenly and compression is great.. It makes no sense!! I really, really dont want to sell it.. But its really looking like i'll have to..its embarassing being passed up hills by little 4 cylinder saturns and a few semi's.

Nope, all injectors fire..from what i can tell by the clicking and their resistance.. I have good news! Alright, i dont know what preignition sounds like..or even what pinging sounds like, but i advanced the dizzy a tooth and put it in stock position..it started up a lot quicker and i can floor it from idle again! It doesnt try to die anymore and doesnt backfire! Alright, so after a test drive, i was very pleased with, i listen very closely for any odd noises..and hear a slighttttttt deep sound..but, remember i just had my exhaust redone and may be mistaken it for something else..BUT. I really think maybe it was just out a tooth.. Any idea what this noise is? I mean its idling right at 750 again, i now have brakes again (its not idling too low anymore) It isnt backfiring anymore and it isnt dying when i floor it.. Basically what im asking is, the pinging noise gonig to be louder and more noticable? Thanks!!

Good news and bad news... Exhaust is fixed now..it sounds 1000% better!! it doesnt tick extremely loudly anymore and idles a lot better.. BUT. we still have the no WOT response..and barely any response anyway. Im not saying that didnt help it, because it did, especially up hills. They said both manifolds are warped but they sealed them and replaced all studs and said it shouldnt leak, if it does, itll need new manifolds. Goods news is, they only charged 80$ and fixed a lot, including my dizzy that wont screw in anymore. They fixed it with a zip tie..not sure how ill fix that. BUT. I have a question. I realize the MAF wiring is still in question, but i DID trade MAFs with a friends pathy and it still drove the same. Also, how do i know if the MAF would be a problem? I took off the air filter and placed my hand over the MAF and when revved up hard, it actually sucked my hand flat against it, so i know its not a air or spark problem. I know, i know this topic is getting old but i dont know what to do anymore!!! Compression is GREAT. Airflow is GREAT. Spark is GREAT (blue spark) Fuel-wise, its running lean. from what i remember from the plugs last. What else is there to do? I know the injectors are spraying fine, well, they spray evenly, but..what else controls the fuel? TPS - replaced and adjusted. EGR - blocked off. ECTS - New Fuel filter in tank - Cleaned Fuel filter in engine bay- replaced over a year ago O2 Sensor - New Knock sensor - New Computer - Swapped with working one, No change IACV - Cleaned Intakes - Cleaned Fuel pressure to the injectors - Good The ONLY thing i can think of that might be a problem is the timing is still set to fully advanced? Can this decrease performance? I dont want to mess with it if it wont help it, as the guy fixed it so it wouldnt move while driving (my screw stripped out) EDIT: I retarded the timing just a slight bit away from fully advanced and it idles lower and just bogs the farther away i go from fully advanced. The guy at the shop swears that the dizzy is a tooth out, but i ddont know. I just know i cant go close to the stock setting of 15BTDC because it dies when i get close to that. Shouldnt it ping if the timing is too far advanced? Can anyone think of anything else?? Again, ill mention this..if you gradually floor it, itll rev up FAST. From an idle (500-600RPM) you floor it hard and quick itll just get loud and the RPMs will either drop some or itll just stay there. From at least 1000RPM flooring it hard, itll slowly rev up higher and higher.. Thanks everyone, i really do appreciate everything everyone has contributed to this...

Good news is, they said the manifolds were fine and were able to be re-used. bad news is my y-pipe was also nearly rusted in half..so basically ive been running no exhaust before the o2.. The o2 couldnt have been getting much of a reading, so im guessing thats why my gas mileage has sucked and its had no power..ha! My passenger manifold was nearly a half inch away from the block... It should be done today and ill post back results! Have to say im excited!

From what i can tell, this hasnt been mentioned yet.. There's a ground strap that goes from the alty to the body, did that get ripped off in the process of the BL? Just an idea.. Also, there's a few more grounds that go from the body to the engine around the battery area. Maybe check those as well?

Its in the shop now.. Said my passenger side manifold looked cracked pretty bad.. And broken exhaust studs on driver side.. Looks like ill be getting manifolds from the jy if that's the case..

Okay.. Since I don't have the tools ready.. In just going to let a shop do it.. I as today a friend let me drive his WD21 and holy crap! I didn't know these made that much power. His pushes you back in the seat at full throttle.. Mine just bogs. Okay. I've exhausted all other possible causes for this power loss. And I've noticed my exhaust stud leak is now to the point at idle it hurts your ears to be near it, but underwood. What I'm asking is, but since that leak is so bad.. Can it cause this power loss before I borrow the 300$..thanks everyone..