81 Black L28E

ok everything has been going good sence i got her back up and running ...there is just one thing that is bothering me ....when i start her up in the moring it takes alot of cranking ...and when she fires up she acts cold blooded if i give her gas she wants to die out ...if i flutter the gas and get it to a higher RPM then it go'es away ....could this be my TPS sensor not being set right??? ...it was one of the things i messed with ...
the hard starting i think comes from my FPR it lets all the fuel out after the key is shut off the stock one does not ....also hard startting comes from haveing the timeing advanced ..i do and set it back a bit but it didnt fix the problem ....it seems that if i dont touch the gas at all it will start but run at a lower idle untell it hits warm up ...my z has aways done this ..its just now it does it alot worse ....after a few min's it smooths out and idles really nice super quiet ..and alot of power after its been started it starts good the rest of the day ...other than it being a little lame at warm up ..i am real stoked on her .....

is there some things i should check out to make warm up a little smoother ?????

RodMoyes

I've had a crap idle at warm up for months and months now and nothing has made any difference. I have pretty much given up. It's not the Air Regulator, not a vacuum line, not plugs, wires, cap, or rotor, not the CSV, not an injector leak, not a bad electrical connector blah blah blah... no freaking clue. When you figure yours out, let me know so I can fix mine

Rod.

81 Black L28E

well i used the noid light on my cold start injector clip during warm up this moring ...
there was no light ...i mess with the afm, turned the screw also ajusted my TPS sensor ...we will see how she does

lww

I hope you found it! I'm not sure I can take another one of your crazy 'replace everything that ain't welded down' episodes!

Cheers,
LWW

RodMoyes

I just went through and read my Haynes troubleshooting section and I relaized that there were a few things I haven't checked yet... stay tuned.

Rod.

RodMoyes

Messed around with mine for a while and made some progress. I'm about 85% sure my coil is going out. Re-gapped plugs a little tighter because they were at max gap. They looked like it's been running a little lean... all 6 of them. That is interesting seeing as how virtually every part of the fuel system is new. Might just have been the excessive gap on the pulgs making it look that way, not sure. tweaked a few things and got rid of some of the stumble but it's still not right. Will play with it more tomorrow.

Rod.

81 Black L28E

nice ROD.......IWW you love my replace it all style

RodMoyes

Update,

So last night I replaced the following:
NGK plugs
NGK plug wires
Dizzy cap
Rotor
Coil
Thermostat (with coolant change over)

Also in the last week I have replaced the electrical connectors to all the injectors, the CSV, the air regulator, coolant temp sensor.

Injectors and CSV are almost brand new and show no leakage. The injectors all fire.

Fuel pump, fuel filter and pressure regulator are new.

EGR,TVV and BPT are new.

All vacuum lines are new and in correct order.

Cylinder compression is good.

Valves are properly adjusted.

Timing is dead on the money.

God Damned car still run's like **** when cold, won't idle to save it's life.

The plugs I just took out looked like they had been subjected to a lean condidtion.

My wife just took my car for a spin and when I watched her leave, there was blueish smoke coming from the tailpipe under hard acceleration.

I don't get it.

I have less than two weeks to pass smog or it get's parked and I can't figure out WTF is going on.

I am thinking maybe the air regulator is just no bueno so I'm going to replace it and see if it helps, but at this point, my hopes are not high.

Rod.

s/cL3.0

You shouldnt drive your car until it is all the way at operating temp j/k

NismoZigma

Ive had the same problem and I think I have pinpointed it to one problem... the cold start injector. Ive also had crap startup idle and I'm thinking this could be it. Does anyone have any idea were it is and how to remove it? I read it in a manual but cant figure out were it is on the L28ET.

NismoPick

lol... there ISN'T one on the L28ET engine.

NismoZigma

Really? Damn lol I was looking at it a on this database website but it says "Except VG engines"..... lol im kinda brain dead right now... does that mean that it applies to the VG's or that it applies to the others except the VG engines?

s/cL3.0

LOL.. Thats crazy

NismoPick

applies to n/a engines. the L28ET idle is controlled by the ecu

NismoZigma

So than do I have a problem with my ECU? Lol i got up in a wierd mood and im not feelin my "intelligence" or common sense for that matter kicking in yet. Basically I just want to know what are the possibles causes to this problem. I get caca idle at start up, so I let it run for a little bit. It always idles at about 1200 and it stays there for maybe 30 seconds, than it goes lower to about 800-900 and stays there for about another 30 secs. Than it starts going from 400- 1200 on its own without me applying any sort of throttle. Also can the fuel pressure regulator have anything to do with this?

NismoPick

Could be the air regulator, and/or the hose from the J-pipe to the X pipe on top of the intake manifold... check to make sure there are no leaks or kinks in those.

RodMoyes

I went ahead and ordered a new Air Regulator from the Nissan dealer today. $104.00 list (Minus my dealer discount makes it about 85 bucks). Victoria British want's $109.95 for theirs. It will be here on Friday and I'll see how it goes. My buddy with the '79 is having a very similar problem with his car also, so this should be a good education for us both in problem solving this weird little issue.

Rod.

NismoZigma

Yea this "little" issue is the only thing that is making me a little bit...... not annoyed but more worried about the car. I love the car and how it runs but this little issue is the only thing that bugs me! What makes it more weird is that it doesnt have any problems after it starts running. Onces its up and going there is no problem.

jfairladyz

Definitely sounds like the AR Rod. As far as passing smog goes (and correct me if I'm wrong here) but uh, last time I checked there was no cold engine test If you're going for a smog test the best thing to do is to just leave the car running in the parking lot and have a couple cigarettes while waiting for them to get to your car. A warm engine runs much cleaner than a cold one. So a cold idle problem really shouldn't even affect your emissions test. I understand you wanting to fix it cause it's a pain in the *** but you shouldn't be worried about it as far as passing smog goes.

RodMoyes

You are indeed correct about the test not being for a cold running car, and yes... getting the car nice and hot activates the Cat and makes for a cleaner burn. However, I can't get the idle properly adjusted and the mixture is all out of whack, aside from that, even though it "runs fine" when it's warmed up, it still doesn't feel right. It's like a subtle little "Missfire" at idle even when it warms up. After all the horse hockey I went through to get it passed the last smog inspection, I don't want to take any chances. I'm just worried that if the car isn't running right, there's a bigger chance for failure. I just want it fixed.

Rod.

jfairladyz

Gotcha

I'm just glad I don't have to deal with that crap anymore. That's about the ONLY thing I llike about living outside of CA.

RodMoyes

The damned smog ****'s have me totally paranoid after what I went through two years ago. It's just weird that the problem seemed to happen overnight and now I have yet to be able to correct it. At first it was just irritating, then when my gas mileage got noticeably worse it became downright aggravating. Now, having to worry about the smog crap just takes it over the top. I was actually scheduled for a smog inspection all the way back in February when the tags expired. I still didn't have an EGR tube at the time, so I just got a temporary tag for a couple of months. Next thing you know, that temp was expiring and I still didn't have the car smog ready... so I got another one... then another. This last one is the last chance, they won't issue another temporary now, so it's make or break time. I have until 10/31 to pass it or park it. I finally gave up on the EGR tube quest and I'm having one custom fit tomorrow by a friend of mine who owns an exhaust shop. I really don't expect having a functional EGR to make a very noticeable differnce in the car's running but I know it will affect it somewhat. I will swap out the AR on friday and see what happens. I haven't messed with the air/fuel mixture at all and I don't want to. I know that once you make a change it opens up a whole new can of worms. There is obviously though some kind of mixture issue right now that is not only evasive, it's just plain pissing me off. Very few things will affect the a/f ratio on these very simplistic FI set-ups and I am 99% sure that all of the things that would affect it are working properly except for the AR. So, I should know by this weekend if I have tracked down the problem or not. I'm going to drop it off Monday at another shop (Knight's Nissan in San Marcos) and let him look it over for me. He is the foremost guru when it comes to all things under the hood of older Z car's. I spent 6 months and 1200 bucks two years ago trying to pass smog only to have him look at and tell me the problem within 5 minutes. Hopefully I will have the problem fixed before he see's the car this time, but I just wan't to be sure. This is where the whole male pride thing bites you in the *** every time. Here I am a guy who's very knowledgable and in the business for years having to go to another guy to figure out my problem. I guess even doctors have to go to other doctors sometimes though... this is one of those cases.

Rod.

RodMoyes

So, I call up the guy at the Nissan dealer this morning and ask if my part came in.. He say's "Yeah, fuel pressure regulator for a 1980 280ZX right?, yeah it's here". So I say "You're kidding right? tell me you didn't just say fuel pressure regulator." He replies with "Yeah, fuel pressure regulator"

Stupid frickin numbnut moron.

I took a deep breath before my next statement "How did you get Fuel pressure regulator and air regulator mixed up? Do you recall me at any point during our conversation using the words fuel or pressure????"

"Well, I thought that's what you said." Say's the dipshit.

"No, as a matter of fact... I made sure to reitierate several times that it was the AIR REGULATOR I needed. I never even mentioned fuel pressure regulator. So I guess now you're going to tell me that I can't get it until next week sometime and that the part I need is going to cost me more money because you failed to LISTEN to what I was saying!?!?!"

Dipshit say's "Uh... well I think I might be able to have it here Saturday morning... but it cost a lot more."

I say, "So you mean to tell me that after the 7 brand new car's I've bought there, and the massive amount of whloesale parts business I do with you for my shop, you're going to **** me on this because YOU MADE A MISTAKE?!?!?!"

Dipshit say's "Uh how about I give it to you for the same price?"

I say "Sounds like a REALLY good idea. Call me as soon as you get it."

Damn... I have always said, nobody knows less about cars or has their head further up their *** than guys who work in parts houses or dealerships. It never fails. I could not have been more specific when I ordered that part and the stupid bastard still couldn't get it right. So I guess I'll be waiting a little longer to see if the AR makes a difference.

I did get the EGR pipe done yesterday, and it seemed to smooth it out a little bit (Slightly). But, I know that the AR is toast and most likely the rest of my problem.

Rod.

jfairladyz

Thats why they stick em in the parts department Rod. They couldn't possibly get by in the service department and the dealer probably figures that the computers will help them get through any rough spots. I applied at a dealership once when I was just outta highschool and they didn't have any openings for the service department and I figured I could work my way up so I applied for parts. Well you know why they didn't hire me. Cause I didn't have enough experience on a computer. Never mind the fact I knew what I was talking about as far as the cars were concerned. They got dipshits behind the counter who don't know a fuel filter from an air filter and they won't hire me because of lack of computing experience. GO figure. And the funniest part is that I've never been turned down for a job physically working on cars. I have however been turned down for everysingle behind the counter parts job I've ever applied for. What's that tell you. They WANT dipshits behind the counter.

NismoZigma

Update on my problem. Yesterday I turned the car on, it started idling, seemed like it was gonna die, than all of a sudden there were explosions coming from the engine, like pops. Now im worried cause it wasnt doing that before! I think im gonna change the distributor and cap see if thats it. What would you guys suggest?