Okay, to start off, a little bit of back story. I purchased a 98 SE from a guy in AZ in June. Car was advertised as pretty much perfect condition and ended up being anything but that. So, over the summer I pulled the engine and transmission. Short of pulling the heads, every gasket on the engine has been replaced. I also replaced the diff bearings in the tranny and installed a quaiffe. This was all in preperation for installation of a V1 T-trim with Matty's plate kit. Things that affect engine performance at this time:
V1 T-trim w/3.25 pulley
3" custom piping
MEVI
370cc injectors - cleaned by deuchwerks
Stock MAF (have new 300z MAF waiting)
AEM FPR
Cartech FMU
Cattman Headers
Catback exhaust
New O2 sensors
New knock sensor
NGK copper plugs gapped at .034
Walborro 255lph pump

I won't get into the hundred or so other parts that had to be replaced, they don't have anything to do with how the engine is running. I started the car up for the first time over a month ago. It started up after 4-5 cranks on the first try. Ran really rough, then white smoke started billowing out of the exhaust, with a REALLY strong smell of fuel. My wideband read 9.5 AFR, so I know it was SUPER rich. I adjusted the FPR as far down as it would go, which only netted a drop to 38 psi. In changing out the return orifice on the AEM, a fitting broke, and I got stuck waiting on a new one.

Fast forward to today, changed out to a larger return orifice (comes with 3 different sizes to control flow back to the fuel tank), put in the middle size, started it back up. Now the fuel pressure has dropped to 28 psi, I still think it's too high, and once again, white smoke smelling of fuel billowing out of the exhaust, and running rough. I'm reading -19 in my vaccumm, which is quite as low as I would like, but I may need to play around with the Blitz BOV to get it any lower.

I believe I may have one of three problems at this time, and I would like some feedback.
A: Fuel pressure is still too high - I believe it is, but I don't think it is high enough to cause all that fuel to billow out the exhaust.
B: Dead cylinder - Either from too much fuel fouling out a spark plug, or some other issue. I have no check engine light on, but I need to pull codes to be sure
C: Torn fuel injector O-ring, or stuck injector - I used lube to install them and they all went in easy. I also had them cleaned and they all tested good.

I have a Z32 MAF and an Apexi AFC to control it, but I want to get the car running properly first before installing them to limit the troubleshooting I have to do. I'm going to pick up a new set of plugs this week (they are cheap enough) and then pull the ones I have and see if I can find evidence of anything. I'm not sure why my fuel pressure has not dropped more. Supposedly, the AEM is good for up to 1000 HP, that thing has to be able to return a lot of fuel, and the second orifice should be large enough. The orifice also controls the responsiveness of the FPR, so I don't want to go with the largest orifice unless I absolutely have to. I need to see if I can borrow a code reader from somewhere and hook it up with the car running to see what codes I get back as well.


Any thoughts or suggestions? Sorry for the long read. We had snow flurries today while I was outside working on the car... need to get this worked out quickly...

How long have you been running your Injectors ??
Have you pulled your plugs to see if they are wet ??

You might want to install your Z32 MAF and see if anything changes with how the car acts. Youd be surprised on how much will change and how great your 370's will work along with the larger MAF.

With the Fuel pressure, what FP are you shooting for ?? You should be ok right around 34 psi at idle (vaccum on) with your setup. I dont know why your shooting so low ?? 28 is pretty low with the injectors your using

Keep us updated on the Plugs.

Thanks for the reply Matt. I installed the injectors while I had the engine out, total run time on them right now, probably less than 10 minutes. Running 9.5 AFR, I didn't want to keep the engine running very long, worried about washing down the cylinder walls with all that fuel. After doing a ton of reading on here, it seemed like most people recommended 20psi as a base fuel pressure with 370cc injectors, though I suppose advice on here has been sketchy at best at times.

I'm going to pick up a new set of plugs today and will try to install them tonight depending on the weather. This wouldn't be the first time I had a brand new set of plugs foul out on me on a boosted car. I had a brand new set of Iridium plugs foul out the first time I started my KA-T, and no amount of cleaning would make them work after that.

I'll post again after I check out the plugs. If I pull the plugs and some are wet, and if I am getting one or more cylinders flooding after I change the plugs, I am going to suspect a leaking O-ring. I really hope the plug change does it though, as I don't want to pull the IM again to get to those rear injectors.

I'd really like to get a base running car before installing the Z32 MAF, one less item to troubleshoot. I don't plan on going into boost until I break in the clutch anyway, so at least a month after I get it back on the road. When I boosted my 240, I had some issues getting it going at first, some of which had to do with the Z32 MAF I was running. Once I got it going good with the stock MAF, I re-installed the Z32 and everything was fine.

what is your AFR now that your FP has dropped to 28psi? you said it was 9.5:1 before, is it the same now? is that a true reading, or is that just as low as your wideband reads, and it has it pegged on the lowest value? first thing to do is check those plugs and replace them with some $2 coppers, just to be sure. we were troubleshooting almost the exact same issue on my buddy's turbo civic and had checked EVERYTHING including swapping out ECUs, checking all the relays and wires in the car for continuity, etc. turned out to be something as simple as fouled plugs that were making it idle so badly lol retarded.

i've never messed with fuel pressure much, my previous setup did not have an AFPR or FP gauge (just stock), but it would start on whatever the stock FP is with a walbro, with purple 370s - though it was a bit difficult and required some cranking and pedal work. now that I have the AFPR, set at 38psi base, and Z32 maf, the car starts up like a stock vehicle. fires on the first try every time, including the first crank i did after the motor swap, it's beautiful. that is with a Z32 maf though remember so a z32 maf has my injectors pulsing shorter than your A32 maf does.

i just thought of another thing you might look at, dirty or bad A32 maf.

Are you sure the FPR is plumbed properly? If I remember correctly it should be on the return side. If I'm wrong someone please correct me.

yes it should be on the return side

Fuel lines and components are installed correctly. Stock regulator was removed and replaced with -6AN threaded fitting. Line runs from return side of fuel rail to the FPR inlet, from the FPR inlet to the inlet of the Cartech FMU, and from the return side of the FMU to the return line back to the tank. Cartech has no adjustment made at this time, and should not be affecting fuel pressure. All components were purchased brand new.

Read this it may help!

http://www.automotiveforums.com/vbulletin/t466912.html

you might want to check out your oil if you flood out your cylinder,last time mine was flood with fuel and we had to put in some cheap oil to get it start.

Umm yeah, that was useless, but thanks anyway.

I would double check the injector o-rings. I had a fuel problem but didn't know the wideband reading, the car would hestiate and ping. I pulled the fuel rail and cranked the car ti see if the injectors sprayed properly and for any o-ring leaks. Everything was good. Came to find out the update I installed in the emanage would not confirm my settings so the 370s were getting stock pulse without correction an putting out to much fuel. Finally removed the update and the car runs like a champ (I'm still n/a). I would install the z32 asap and see if that changes anything.

did you post the wrong link by accident?

Yeah but I forgot the link I wanted to post. Since I'm now on medicare senior moments are part of life! I'll try to find the right post.

2 things caused the same problem in my car in the past,

1- somehow my coil wires were shorting out on the engine. I traced them and put em in order and retaped all suspicious spots.

2- The maf sensor was shot. By the way since I use the JWT ecu and have the car tuned at his shop, how do you adjust the fuel, air, and timing map on the computer to use the Z32 MAF?

I really have no experience with any other electronic units that fool the oem sensors which then changes the ecu maps.

I finally had time today to start working on it. Pulled the front bank spark plugs and ALL of them were sooted up and wet with fuel. I decided to take Neal's advice and just put in my Z32 MAF. Got everything wired up when it started to rain, so that shut me down for the day. I'm hoping for a break in the rain tomorrow morning or sometime this week, I'm going to get the piping re-installed and replace all the spark plugs and go from there.

Finally, no rain, but also no success.

Replaced all the spark plugs with new. Found the source of a vacuum leak and took care of it. Wired in the Z32 MAF, triple checked the wiring, then hooked everything back up. Started it up, CEL on, fuel vapors pouring out of the exhaust, STILL, running the same. Running at 9.5 - 9.8 AFR at idle.

Pulled the codes, 0100 and 0105. The Z32 MAF I have is pretty much brand new, but I suppose it could be bad. I don't believe it's the issue though, since it ran exactly the same way with a good A32 MAF. Vacuum is right at -19 at idle. Idle is crap and I can here is missing when I rev it up at all.

Next steps? I'm going to try tested te Z32 MAF on Iansw's car to see if he has any issues. I thought about going back to stock spark plugs and gap to see if that improves anything, long shot that it might be.

Car has not been fueled since July, and tank is pretty low, anyone think bad fuel may be playing a part?

Last thing I can think to do is pull all the injectors and replace the O-rings, I really don't want to pull the manifold again, but I think I am at the end of things to try.

Thoughts or comments???