rcb280z

Cool! Thanks

Yeah, and it's driving me nuts. Something so simple isn't working. Everything has tested good so far. Unless I am missing something. I'm debating taking my Z to a well known Z shop in southern Ca but I don't want to. I took it for a short drive a little while ago and I am not happy with the way it's running. It feels lean. A little loss of power. Coasting to a stop it's popping through the exhaust. pop.pop...pop....poppop..popopop....pop. Running warmer than usual (lean). When we put it on the dyno yesterday it was rich, 1.8% co. Not too bad but by CA standards not good. And I talk to people that have no trouble with they're Z running at CA standards, 0.5% co's. Sorry if it seems like I am rambling on. If I could erase everything and start from scratch I would.

Fastwomen, I was just thinking on the lines of checking fuel pump operations myself. As far as the CSV goes, if my problem is a rich running condition on cold start up then unplugging the cold start valve prior to start up might tell me something. I'm looking for her to fire up and idle at 1300 (+/- a couple rpm) like she should on a cold start. The problem here is it doesn't start up right after sitting over night. But if I run her in the am and later, say 3-4 hrs later, I start her up she immediately hits that 1300 rpm spot and warms up as expected without me manipulating the throttle. I have to manipulate the throttle on an over night cold start up. I hope you are following me. I should be able to reach in, in the morning and start the car and it idle with no problem. No, I have to throttle it up for about 10-15 seconds for it to stay at that 1300rpm range during warm up. But only for an over night cold start up. Doesn't make sense. I think I'm chasing my tail and missing something that is actually a simple fix. Maybe?

Are the 77 and 78 dash gauges interchangeable?

No change on cold start!! I'm going to unplug the cold start and see how it fires up tomorrow morning. Maybe it's dumping too much fuel. I don't quite know which direction to go in next. AFM adjustments, calibration have changed nothing. Kind of lost now

If you can even find one would be a miracle in it self! I looked for a couple of years and got lucky one day when I was visiting friends in Vegas. Went to a salvage yard there and there was a 77 with same prod date as mine! I paid 125 bones for that harness. Now if I need I just repair what I have. You can do a search on this site for connectors also. Good luck man!

Purchased a 0-60 psi fuel pressure gauge from Summitt racing about 6 months ago and it is faulty (I think). It periodically reads incorrect. Anyone else have the same issue? If so, which pressure gauge do you use now? Thanks.

I will post tomorrow on the cold start results. Be watching

My gauge is faulty. I just ran your test again with the engine off and got nearly 38 psi.

Right? I hope.

Ok Blue, will have to try that next weekend. I checked fuel pressure with engine on and as I rev'd the engine it would read 36 to 40 psi. This is good IIRC.

My buddy has a friend with a dyno and he let us use it today. We were able to tune the AFM using the dyno today. Boy was this thing off! We actually dialed it in to CA requirements. It was a little lean for our taste so we richend it slightly and it was running ok after that. We will have to see how it affects the cold start in the morning. Now on to the fuel pressure issue.....

Unless there is something wrong with my gauge I only get 30 psi with Blue's test

Ok, before I post everything I did today I need to run something by you all that I think will help solve my issue. I had hooked up my vacuum gauge, and tach/dwell meter so I could observe rpms and vacuum will running my tests. I just happened to look up at my fuel pressure gauge and noticed the needle dropped suddenly from 28 psi to about 23 psi and then back to 28 psi. This was all while the car is running. I'm now staring at the gauge, things running through my head, and it slowly climbed to 30psi. I thought maybe FPR. I had a new one in my arsenal so I replaced it. It was holding at about 26 psi now, car running. I went over to the fuel return line and pinched it until I got a reading of 32psi and the car idled better. So my question is; if I'm able to increase the fuel pressure and the engine runs better I could have a fuel pump issue correct? Fuel flow through the injectors only changes if the ECU says to right? not because there is an increase in pressure.

xubuntu, I did a very thorough AAR evaluation including the pinching of the air supply hose running to it and there was no change in the way the car idled, unfortunately. Because if that was it I would be happy that I found it.The test results are outlined in post #45. Thanks for the website...will be looking at it next. When I'm done with this issue I want to talk to you about your cs-130 alt. upgrade.

26th-Z, my point is; if I don't need to burn a higher octane (money wasted) then why should I? I agree....it takes maintaining your vehicle to obtain optimal fuel economy as well as performance. If I am spending more money than I have to....why am I? BTW nice avatar!

Hmmm....great info there Gary. I run with 10-12 deg. of timing so I am going to try a tank of 87 to see if there is a difference.

Here we go again with fuel prices going way up! I currently burn 91 octane (Nissan recommended) in my 77. But, with prices topping $5 a gallon supposedly soon that will be expensive. So, what do you feed your Z's tank with? I'm thinking maybe dropping to a lower octane and adding a fuel additive every other tank. Anyone burn lower octane without issues?

Thanks Bonzi Lon, and mgood. Now I have what I need.

What year is the Z? Look at your climate control panel....what is the top left lever on? Is it on a/c or heat or...?

Will be running tests all day (unless I find something quick) Sat. And will calibrate AFM to eliminated the possibility of it being faulty. Will post results then.

No problem. Thanks for the help

Ah yes! perfect. Can you send one of the opposite end of the window frame where the frame meats the door also grantf? The really small piece. Is that original or did you have to replace it? Did you use regular W/S cement? Sorry for so many questions. I purchased new ones several years ago and when I attempted (recently) to install them I couldn't remember how to! Thanks for your help. I looked at the FSM but it doesn't make sense.

Koalia, guess no one has the weatherstripping either. We are all probably missing it.

Whats wrong with EFI. What year is it? I might want it.