So last night I drove out to a buddys house to pick up some stuff. I popped the hood and he was lookin around at the car. I reved up the motor just enough for the blow off to go. Then we started talking and the idle started fluctuating by a few hundred rpms. Up and down over and over again. I figured it was just my emu being a pos again and left. As soon as I pulled out of the driveway the car ran like ****. Barely puttered to 2000 rpms. I pulled over and it eventually died. No vaccuum leaks I could see/hear. I checked the ecu for codes and it gave me crank pos sensor, ignition signal primary, and the evap code I always have. I changed the crank and cam sensors and the idle changed slightly. I also disconnected the emu ignition wires, since the emu is a broken pos and has a mind of its own. I now have no codes. I changed the MAF and no difference. All my couplers are nice and tight. Fuel pressure is normal. The exhaust smells like raw gas. I tried unplugging one coil pack while it was running. No matter which one I pulled, it made almost no difference in the idle, but when I pulled 2 it makes a huge difference. I am at a loss about this and Im worried I might have lost a cylinder. Mods can be found here https://my350z.com/forum/forced-indu...98-maxima.html Someone please help me!
Zack

 

Coil packs mixed up?

 

As in do I have my coil packs plugged in wrong? No

 

Bump! Anyone?

 

Check vacuum lines again, if it started out of no where (especially after a blip of the throttle).

 

As far as I could tell (without a boost gauge) I couldnt find a vacuum leak. All the couplers were tight, and all the hoses are connected. Im going to try swapping injectors, swapping coil packs into a buddys car to see if one is messed up, and then checking the plugs. I also was thinking my intake manifold gasket could be leaking? Im not sure. I just cant think of anything else. Could I have lost compression in a cylinder perhaps?

 

I chased an issue for ever and it was a melted vacuum line I routed too close to a turbo

 

Well its definitely not the injectors, I swapped them and no difference. I noticed one of the plugs was soaked in fuel and the rest were dry. I triple checked and there is definitely no vacuum leakes. Hopefully it is just a coil pack, but I wont know until tomorrow. If anyone else has an idea, please throw it out there.
Zack

 

did you check the plugs? it seems like your just dumping a **** ton of fuel and nothing compensating it.. and make sure your injector wiring is all nice and tighty they could be just suck on on you know (when i did a supra injector upgrade, i had problems with the injector dumping too much fuel and bad idle because the injector wiring was shot ie. injector cables were touching each other caused a short)

 

I forgot to add, I checked all the wiring already. I did feel a small leak from my maf adaptor. If this is the problem, why all the sudden would it leak when its bolted down!?!? anyways the only other thing is the bov. I noticed the o ring in the flange looks a little off, but I do not have snap ring pliers and I didnt feel a leak from it. Im tired of this!

 

^thats the game man. little things like this are expected to happen to all of us. this is not a stock car any more, its transformation has and will give you bumps always.

 

the plug that was soaked in fuel, try dis-connecting that coil and see if there is any change.

 

I just performed a plug change the other day, and I managed to lpug in coils 4 and 6 into the wrong plugs. easy mistake as the plugs can go to either coil without an issue. the car would start but idled horribly, it would barely rev, had a major odor of raw gas, and my A:F was 20:1.

Once I realized the issue, I fixed it and, of course, everything was perfect.

 

thats an easy one to do, specially since number 6 coil mounts backward compared to other 2.

T

 

he said he already checked the coils..

 

Crankposition Sensor

 

He already changed it.

 

I changed the crank ref and crank pos sensors

 

what EMS do you have?

 

I seen this post while trying to find a solution to my problem.
I have a 2004 350Z with 40,000 miles,
http://picasaweb.google.com/rodnhower/350Z#
It was running perfect, then in a matter of 1 mile it started with a backfire, then I seemed to loose cylinder after cylinder.
The Nissan dealer says there was a short to ground in the wire harness which
proceeded to take out ALL of the ignition coils.
Just wandered if anybody heard of similar problems due to poor wire harness routing.
Thanks!
Rod