rcb280z

Wow! and they used to sell for under $50.

Yep, have that on my list of things to get from Autozone today.

Haz, I said I removed all relays but now remember I did not remove the EFI relay. I did leave it installed. Removed everything else. Blue's right, that's why I said check your fuel pump circuit. Not sure if its the same as the 77. It looks like the 75 use's a different EFI relay than the 77. At least it seems that way, there are two different part numbers. So my way of wiring probably wouldn't work for you anyway. Besides I still can't completely remember what I did. It was 1994, 21 years ago. Sorry I couldn't be of much help.

Cool, thanks!

Yes it will work Haz. That is what I did with my 77 when I was running SU's when I lived in Vegas. I did pull my ECU, harness, and relays. I don't remember, not surprised, how I powered my fuel pump. I know I wired it directly to the ignition somewhere, just don't remember exactly. I did use the stock pump harness in the back. For some reason I want to say I had to pull the passenger seat to get to the pump wiring. I will think about it some more, maybe I'll remember it, and post it. Oh!, I ran a wire from the bullet connector under the passenger seat to my ignition relay. But, check your fuel pump circuit in the FSM and go from there. Not sure it's the same as mine.

Thanks Capt. It only seems like a vacuum leak when the BCDD solenoid activates at idle when it shouldn't activate. Otherwise it runs good. Might just leave things alone for now unless things worsen. Yeah the dash cap thing is an issue for me too but if you could have seen my dash you would say "oh I understand", ! Some of the cracks are so wide that you set a Taco Bell taco in it . Even have a crack starting in one of the gauge pods . I would remove the dash and fix it but I don't have that kind of time. So the dash cap will have to do for now.

Which chrome vinyl strip did you get Haz? There are a lot available.

That looks awesome! Good steady hand too. Did you use an exacto-knife? Going to have to look at the dog legs on my 77....don't recall there being a strip on mine, hmm... Never mind on the knife, I see it now. Had to look at it again, nice! How did you get your door panels to look so good. They look brand new, are they?

Yeah, I have both books and am reading them nightly myself. Im hoping to have to only do the head though.

Yeah that oil bar is getting rubbed on the end. Probably can hear it too. I need to do engine work also. Are you going to post the process site?

Yep, solenoid is good. I did that test first. Thought we were looking for something in particular, other than the click. Maybe one day when I have the whole day to spend on the Z I will remove the throttle body and open up the BCDD to check the diaphragms for holes. I can disassemble the throttle body and clean it up as well. Unless its not a good idea to open up the BCDD. I see where people have done it but the FSM doesn't recommend it. As far as an external leak I don't think its the case because my intake vacuum stays between 18-19in's. If I had a leak it would probably show up on my vac gauge right? But, when the solenoid actuates (when its not supposed to) it does seem as if there is a vacuum leak and I don't recall a change on the vacuum gauge. Something to pay attention to next time I look at it. I hate walking away from something until it is fixed so I will continue until I figure it out. Pretty sure it is speedo related though. Next will be to try and remove the speedo with the dash cap still installed. I think this will be a bigger issue than the BCDD. Thanks to you, Capt and Zed Head, for your time in this.

Duh. Well of course it didn't do it when you were looking for it! Ha! don't I know it. Well it definitely isn't that bad then....idle is just a little rough when it energizes, nothing too serious. It's a 5 speed. I thought the idea of the BCDD was to introduce extra air into the intake. Thought that was what it took to keep the rpms up high enough while the BCDD is activated. So I should remove the solenoid and test it?

Update, Capt., yes I agree after thinking about everything for awhile. It is an intermittent electrical issue I believe. I performed the test in the FSM (EC-5) and got good results. Put rear end up on jack stands, ran the car up to 15 mph, and had voltage between A and B at the test connector. And no voltage at idle. So it must have been working at the time of the test. I waited to hear the click so I could test again and it wouldn't, of course! Now that I'm looking at it it's not going to act up! Figures. So, what's the worse that could happen if it continues to do this intermittently? Leaner at idle? I'm trying NOT to have to remove and replace the speedo that I just put in about a year and a half ago. I have a full dash cap and remember trying to remove the tach once and gave up because I couldn't get it out. My next test should be of the amplifier and speed switch though if I read it right. I have another speedo in a box (used) so hopefully its good. I wonder if this has happened to more people like specifically the ones that believe the ecu is "floating lean" I think they called it. That's what it feels and looks like...a lean condition when the solenoid activates. The bullet connector is corrosion free also, made sure to add that info.

If you are getting rid of the fuel injection I would be interested in the BCDD if you are willing to part it out. If you don't want to part out, what would you want for the complete intake. PM me.

Hope to do all this tomorrow and post results.

Haha! I know. Hope its a good reading. Im hoping the BCDD just needs to be adjusted but my luck...... Yep, thought about corroded connections already, sorry should have posted that. Also going to remove solenoid and check that its not all gummed up

sscanf has a lazer cutter to make those perfect "cutouts". Wish I had one. Thanks for the thread.

Capt. unfortunately here in CA we have "rolling dyno" emissions tests. So, it would benefit me to have mine operating correctly, I believe. What a pain. There is a 15 mph test and there is a 25 mph test. So I would assume that on deceleration, without a good functioning BCDD, HC's would load up.

Ok so I just looked at it a 3rd time. I need to test the amplifier at the back of the speedo. Hope that's not the problem. I have a dash cap and I don't think you can remove the tach or speedo with it in place.

I completely understand. I'm just trying to see if there are any available in case mine is bad. Thanks!

Hey Capt. I started a new thread regarding my issue. Thanks for responding. You'll see it.

Zed Head, I did read that section of the FSM. So if I read everything right there may be an issue with the amplifier on the back of the speedometer correct? Or can this be because the BCDD is out of adjustment? I do believe it is after reading that section in the FSM again. But need your opinion. I decided to unplug the solenoid at the bullet connector near the BCDD and got an unstable idle. Im confused now. Somethings not making sense and I can't put my finger on it.

Update, I think I can say without a doubt there are no parts available to repair these valves. Haven't had too much time to put into solving my issue yet but I am hoping someone has experience with these things. Obviously I do not.

How about anti-fog by Rainex? Anyone try it?

Hey Haz, a little off topic but you wouldn't by any chance still have the BCDD for your 75 would you? If so was it working that you know of? I started a thread about an issue I'm having with mine and not sure which direction I'm going to take yet. Whether to remove it or not that is. If yours is working would you want to part with it? Bob