1977 280z lean in 4,5,6 rich on 1,2,3

[Zed Head]

1 hour ago, Zed Head said:

If your engine has the ballast resistor then gap to 0.32".  I haven't found an FSM that I'm sure is actually 1977, so there might be specs showing 0.43" gap.  But I don't think that's right for a ballast resistor system.

Didn't you have a post about where to put the condenser wire?  There was discussion about the ballast.  I think that you have a ballast resistor, so you should use the smaller gap.

1977 is a "change" year, Nissan seems to have changed many different things all in the same model year instead of waiting for a new model year.  And, even on this site, you'll find different versions of the 1977 FSM.  Nissan didn't put the year of the FSM in the document, for some reason.  Edit - actually it's only on the cover or the first few pages.  But people often don't copy those . 

You just have to know.  1975 has a similar problem.

Edited August 24, 2020 by Zed Head

[240zadmire]

@Zed Head yes sir.  I needed help about a wire goes nowhere from the condenser.  I do have the ballad’s resistor.

will open spark plugs soon.  I’m pretty sure the gap is wider than suppose to.  Don’t have the handy spark plug gauge.  It always on the checkout counter....  I had one years back and kept thinking it’s in my tool box somewhere... as soon as I bought it, the one I had will magically appear.  Always like that ?  will use the valve gap lash instead 

 

stay tune

 

regards

 

[240zadmire]

Dump question,

I believe I swapped #1 fuel injector connection.  #37 goes to dropping resistor and #15 to ECU.  Look like I screw up on #1 resistor because when the engine is running, pulling a spark plug on each engine, RPM lower immediately.  #1 has no effect.  I swap fuel injector from #2 to #1 to see if injector works and it does.

regards

 

[240zadmire]

Indeed I screwed up the wire of injector #1. Fixed that and pulling any spark plug lower the rpm immediately.  Lost 1/6 of al the horse power. ?

Adjust the spark plugs gap to 0.039.  Was about 0.045 or so.  Will get the proper gap gauge tomorrow.  Checked the resistance of each spark plug wire and approx 7k ohms. Well with in 30k ohms by FSM

Checked the gap between rotor and stator to be spotted on of 0.08

 

Next would be adjust the air fuel ratio procedure .... fun fun fun.  Sweat sweat and more sweat 

 

[dutchzcarguy]

7 hours ago, Zed Head said:

gapped at ~0.32".  If your engine has the ballast resistor then gap to 0.32".  I haven't found an FSM that I'm sure is actually 1977, so there might be specs showing 0.43" gap. 

Eh... guy's am i mistaken.. a gap of 0,32 inches is 8,1 mm!  Just wanted to let know you must mean 0.032 of an inch...  oh such fine stuff....   inches and miles...  sorry ?  (I'm metric..)

(EDIT>>  I did'nt read that last post.. there it's correct at 0,032")

Edited August 24, 2020 by dutchzcarguy

[dutchzcarguy]

BTW should there not be NGK -BPR6ES plugs in that engine... you use a Iridium type? any good expirience and wich ones are those?

[Zed Head]

I screwed up and left a zero out.  0.032" is correct.  

[Zed Head]

12 hours ago, 240zadmire said:

so for adjust to run a leaner without tampering/fiddling the AFM, there is a screw behind the AFM flapper.  Is it enough/right place to add more air to trick the ECU running lean?

The screw in the AFM is for idle air adjustment.  It won't have much effect at higher RPM.  Best not to mess with that, it's set at the factory.

 

[siteunseen]

7 hours ago, dutchzcarguy said:

BTW should there not be NGK -BPR6ES plugs in that engine... you use a Iridium type? any good expirience and wich ones are those?

I agree with that. When I first started fooling with Zs again I bought those little pin sized electrodes. They were dark like yours. The bp6es copper work best for me.

[Zed Head]

Here's some confusion, for me anyway.  I had always assumed that the ballast resistor was used because the ignition model did not use current-limiting control.  And without the ability to "fill" the coil the spark plug's  gap was smaller.  And that it was spec'ed larger in 1978 when the better ignition module was introduced.

But, here is the actual specification from the actual 1977 Owners' Manual, with 1977 on the cover.  I don't really know what to make of it.  It seems to imply that plugs without resistors will fire across a larger gap.

Also note that Nissan did not recommend the projected tip plugs although many of use use them.  Nissan recommended the P tips, then they didn't then, they did again for the ZX engines.

[240zadmire]

@dutchzcarguymentioned about BPR5ES... light went up in my head I do have a set.  It came with the car. Talking about letting stuff go eh.... it look really new, to me.

i don’t have the fancy tool like this one

 

Use a sled hammer probably over kill, although at time it is really satisfy and justified ... so I used a clamp and a sockeat to do the job.

gently turn the knob/handle and check the gauge.  Do it couple of times and you’ll master it.  I know it is not conventional and probably outright wrong. Got to do with what you have. 



 

still trying to fiddling the retarded, and the screw underneath the distributor.  
 

the by pass screw seem tampered as it is protruded way outside.  Like flat to the body.  Can’t be true as it is loose as well.

Will take pictures both iridium and standard BPR

 

stay tune

 

Edited August 25, 2020 by 240zadmire

[240zadmire]

ok, a cool breeze tonight... not complaining as other are much less fortunate such as north California that is burning days already.  May God send some rain and strengthen to those firefighters.

 

i did 2 experienced with Iridium and BPR5ES. Each ran idle and some rev here and there for 30 minutes.  All engines fired as I pulled the plug individually and RPM dropped as expected.  Retarded 10 degrees with idle approximately 850-900rpm.

 

no more sooty/powder smog on any spark plug. Please see the pictures.  I think it is still run a bit rich or just right.  When I replaced my sedan, the plugs much drier and whiter if that describe it. But again, the plugs in my other sedan ran for 80k miles. Can’t compare to this.

 

i think the BPR look cleaner than the Iridium.  I sniffed smog on both set of plugs (Use all senses, stupid me but got to find a way ...) and definitely not as strong as before.

Saw a clip on you tube howto adjust fuel/air ratio but need to drill a hole on the exhaust pipe to put the CO2... not a big fan but is there any other ways to guesstimate what is the right mixture?

what do you guys think?