Z_WRECKER

well maybe it is your stock fuel regulator or somethng... i am in dark about this one 91

91zxtt

I just spent an eternity on 300zc. I must say that this site is much better. That damn thing is so big that it's hard to navigate through it. Anyways, after much searching, I've found that the spark plug gap for the PFR 6B-11B should be set to .035" - .038". I didn't even check that. I'm guess it comes set at .044" for the N/A. The stock N/A plug is the PFR 6B. The stock TT plug is the 5B. Both are .044" stock. At stage 3, the TT goes to cooler plug and a smaller gap. I'm going to check my fuel pump and several other thinigs this weekend. I'm also going to replace my coolant temp sensor connector, all 6 injector connectors and all 6 coil pack connectors. I'll use a small file on all of the coil and injector tabs. At that time I'll re-gap my plugs. I find it odd that was unable to get a reading from my TPS. I could have a problem there as well. There's a TPS on ebay for $15. I've read that there is no need for an aftermarket adjustable FPR. Some people who have 600+ hp Z's are using the factory FPR. It would be nice to be able to bump up the fuel pressure if I ran into lean problems donw the road. So, in summation here is what I've narrowed it down to....
Fuel pump ($261)
Fuel pressure regulator ($68 OEM / $113 NISMO adjustable)
Fuel dampener ($66)
TPS ($75 new / $15 used/ebay)
Incorrectly gapped plugs (0)
Connectors....Coil packs, injectors and coolant temp sensor. ($82 - $44 - $15)

It's still a wild goose chase, and an expensive one at that.

Z_WRECKER

whatever you do my man.... may the force be with you, and i have no doubts that you will find the problem

91zxtt

I just don't like being able to hear my credit card whimper.

91zxtt

Are the coil packs on the TT and the N/A the same? They have a different part # according to courtesyparts. I thought someone said in another post that they were. I couldn't find that thread. It makes sense to me that they would be because the stock N/A plugs are the 6B-11B; which is what's recommended on stage 3 and up TT's. Please advise. Someone is selling some on ebay; which, if they are the same, then I'll buy them.

CanyonCarver

it was this one

https://www.zdriver.com/showthread.php?t=9809

tt dan

haha.... i know what you mean.... im in the process of trying to fix my z too.... one of the injectors is leaking, i need some new connectors for the coil packs, ect...... can you get those from anyone becides the nissan dealer? i tried autozone, and they said that they cant get them.... just wondering.... good luck w/ the search tho..... you'll find it eventually, your gonna run out of stuff to fix

CanyonCarver

I have yet to get to that point on any old cars.............

91zxtt

Awesome!! Thanks. If $ wasn't an option, then I could see running out of things to fix, but it would only be temporary. Something will break later. That's not reality though. For you and I, we'll always find something to fix, or at least tinker with.

Riz Z Speed

Your card whimpers?
Mine just askes for Tylenol because of all the time it spends banging against the limit.

CanyonCarver

mine have this artificial limit of about $2500 month. Except everytime I buy something like a z or a motorcycle on it they just up my limit. The last I looked one now has a limit of $32k.

91zxtt

Credit card companies are funny that way. They won't be happy until America is buried in debt. It's unfortunate that so many people fall into that trap.

Z_WRECKER

i am debt free....except some 15k i have left to pay off on my wrx

tt dan

i should try putting some tylenol in the gas tank, mayble that will help... lol..... i couldnt even drive it to work today, it fealt like it was gonna die half way down the road, i had to turn around and take my moms car it sucked, im gonna wake up early tomorrow to look at it tho.... i think there may have been a little moisture on the intake, making in run that crappy.... it poured the last 2 days... so , hopefully its something stupid like that but wish me and 91 luck

91zxtt

I found a couple of interesting things yesterday. The TPS was way out of adjustment. At idle, it shouold put out .4-.45 volts. Mine was putting out .21volts, so I adjusted it to set idle at .4volts. Also, at WOT, it should put out .4volts. At the new idle setting it was putting out 3.8 volts. The full throttle stop was getting in the way, so adjusted that back. Now, I'm at .4 volts at idle and 4.08 volts at WOT. I also adjusted out the slack in the throttle cable. It was surprised at how much there was. I adjusted out a good 1/4"-3/8" of play. A new problem though....I can't get the idle down. I disconnected the connector at the FICD...adjusted the idle to 700 and plugged it back in. The idle jumped up to 1800 and stayed there. Why???? I drove it home. By the time I got there, the idle had dropped to 1200. Puzzling. I'm going to take the whole idle control unit apart (air regulator, FICD, AAC)next weekend and clean it out. I'm guessing something is plugged in there. Any other suggestions? I'll also be changing the coil connectors, injector connectors, and ECU coolant temp connector. I'll keep you all posted.

CanyonCarver

have you checked/replaced your coolant temp sensor? bad ones cause hi idle i believe.

91zxtt

Yep. It was replaced maybe 2000 miles ago. I haven't checked it cold. I checked it when it was warm and the ohm reading was in between the cold and help specs. I'll check it again cold. My connectpr is cracked, so I'm replacing that. I made a real mess today....I pulled back all of the wiring on top of the engine (coil connecotrs, injector connectors and a bunch of other crap. The tabs on the injectos were green (lots of corrosion). So were a couple of the IACV connectors. I'll replace them all. I took off the AAV, FICD and the air regulator. Nothing looked that bad inside, but I'll clean it all out, retest it and put it back in the car. Since it's duplicate work, I''ll replace most of my vacuum hoses. I meant to tell you guys that I did a leakdown test and found no leaks. The hoses are old and brittle, so it's a good idea to replace them. What comapny sells vacuum hose replacement kits? I'll also be changing my fuel lines. Who sells braided fuel lines? Thanks guys.

Z_WRECKER

maybe some hose techniques.com (sp.) I just got some samco intercooler hoses, and those things are pretty high quality stuff

91zxtt

I saw the vacuum hoses on AMZ's web site for $75. Any ideas braided on fuel line?

This thing is becoming a big pain in the ***. I took the IACV apart. There was some gunk in there, but not much. Not enough that you would think would cause a problem. Everything in the IACV tests fine with the ohm meter (air regulator, AAV, FICD). The internal air regulator flap seems loose, but I don't have anything to compare it to. The idle control valve is a mystery. We cant figure out how the damn thing works....it seems to let air run through everywhere going both ways; which doesn't seem right. I need a sh*t load of new connectors. Alf of the ones going to the IACV are shot. I consider myself to be fairly proficient with a soldering iron, but I oughta be an expert by the time I'm done splicing in these new connectors. I think 1 injector (#6 cylinder) is bad. 1-5 test at 11-12 ohms. #6 tested at 16. I'm going to retest because usually when they go bad it's really obvious. Here's my latest thought....it's an expensive one.... I'm thinking I'll pull the plenum (upper and lower). I'll purchase the honed upper and lower plenums from, gah dare I say it,.... Stillen. They quoted me what i think is a good price today ($550 total for the 2). I'll install the NISMO 555cc injectors, so then I don't need to worry about the whole thought, 'Once one goes bad, then they all go bad.' Plus, with the plenum out of the way, it'll be easier to drill the EGT probe holes and easier to run the boost lines for the boost controller. I'm just afraid of what I'll find along the way. A friend of mine knows the problems that I'm having and all he can say is, "Boy, aren't Z's fun." I keep thinking abouot ow much fun it will be once it's back together. i've never been very good at looking on the bright side of things though. Not only is this becoming expensive, but working on this car as much as I am is going turn me into an alcoholic. I'm hoping to have this all done by New Years. I'm only partially kidding with that statement.

lightspeed

High idle? I have had some luck with DeepCreep, Sea Foam and cleaning my air filter!

https://www.zdriver.com/showthread.php?p=51438

91zxtt

I may have to take back some of the negative things I said abouot Stillen. They will take care of you if you have purchased stuff from them in the past. I think they hooked me up pretty well on what I just ordered from them. They beat the prices on everything I could find online through Z1 and SGP.
Ported and polished upper plenum, ported lower plenum, 555 NISMO injectors, Greddy Profec B SPEC II boost controller. Don't get wrong, it was still expensive, but they did ok by me.
I also ordered some stuff from Z1 today.....the ASHSPEC ECU, DOOLZ and their electric fan.
I have to order a bunch of crap from courtesy, but I'm going to take inventory tonight to see what I need exactly. New brake booster lines, clutch vacuum hoses, IACV hoses and water bypass hoses. I think I'm just going to replace my fuel lines with new factory ones. I can't find anyone who carries braided lines. Wish me luck.

DanZ32

Not familiar with this company but might be worth a looksie...

http://www.paragonperformance.com/

91zxtt

Interesting. It's less expensive than the factory fuel lines. I'll have to call them. Thanks.

Z_WRECKER

$550 for both WOW aren't they like $500 a piece??????

and you are right this is getting expensive...you've been spending some serious cash on this thing, but its only money, and you only live once, so spend all you can

91zxtt

That was the price for the 2 without the polish job on the upper. They gave 'em to me at wholesale. I decided to go with the polished upper, so it kicked the price up $270. It wound up being $820 for the 2. Not bad, I think.