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the dry test across all cylinders was 130 yeah, the dry comp test across all was 130. but when car running, #6 would jump quickly to 90 and no more, it will drop down to 45. if i add little rpm it will fluctuate between 0 & 35. i did same test on #2. i get 90 at start, then 50. if i add some rpm it fluctuates at a much higher range than #6. i think it was between 40~80 i will test the remaining ones today hopefully Q, would you know if the 82 280zx considered a GDI (Gasoline Direct Injection) into combustion chamber or is it spraying into intake? it will dictate how i go about cleaning attempt to remove an carbon build up that may be causing valve to get stuck

yesterday i did the dry compression test, results were about 130 cross all cylinders today i did it while the car was running in order to rule out if car loses compression during operation. i managed to do it on cylinder #6 which recorded 90 at start but then immediately dropped to 45 and remained there. i couldn't finish testing the rest due doctor Appnt i wasnt aware of also one of the spark plug cables was too stuck to plug and ended up going bad. i have to order new set

with my humble experience and seeing what everyone spoke about i will focus on the following 1) confirm the distributor installed 3 yrs ago is indeed for Turbo model 2) get new CAP & Cables 3) use some upper intake cleaner to rule out any carbon build up on the valves. Specially since the live compression test showed very low numbers. Piston#6 showed 45psi 4) continue to follow the FSM to chk other sensors & parts i hope i wont need to look for an EFI Analyzer

results of resistance measurements .... Keeping in mind that my Klein MM300 indicates .3 or .2 when the 2 leads touch, i will assume that's my zero. 1) pin 18 & 25 at the harness, results when depressed = infinity when released = i get anything from 1.9 to 2.2 to 2.5. but nothing less than 1.9 2) testing at the valve looked better. when depressed = infinity when released = .3 or .2

alright going to inspec that now... here is how the injectors sound on the stethoscope. in person injector #6 sounds a lot lower/subtle than what u hear in the recording. Injectors sound.mp4

Got u , i will make several vids as i test each scenario i will also grab a colortTune cause its another cool tool to have i'm aware of throttle valve, but not sure about throttle plate

Folks, im considering a Compression test while car is running for a min or so to see if i have any loss during operation. What are ur takes on that? also, i came across the below. what if carbon build up is causing valves to get stuck or not open/close properly

Hey Dutch, i already ruled out that the new injc#6 to be in a working condition. i posted earlier that i raised the fuel rail far enough to see it spray when cranking over the car. do u still think i should alternate inject 6 w lets say injector 5 or 4 ? are you aiming to see if the spark plug would end up showing rich on 4 or 5?

looking back at the pics, mine reported 130. so i should im good there correct? Q1, are the distributors for the turbo charged 280zx diff from the non-turbo? Q2, what route should i take now to figure out why plug #6 is wet and looking diff than others?

Hey Mark, yes i made sure to push down all the way on the throttle, while my son cranked it over about 10 cycles i noticed all pistons it would get to that 125 range by 2nd cycle

i couldnt tell if i smelled gas. given the exhaust smell in the garage and on my clothing my nose is shot I can confirm the new injector is spraying. so if the rest of spark plugs are looking better now, isnt that a good indication that the Dist Cap may be the issue? i still dont know what would cause plug 6 to look like that if the wiring is good, compression is same across, and the injector is working, and the valves have been set to .008 & ..010 across the board you didnt tell me, whats ur take on the compression being 125. i heard it should be close to 150~180

i don't have a way to confirm if its running on 5 cylinder. i can only confirm that idling is perfect, and it drives a lot smoother. i tested all spark cables resistance from with in the CAP, and its sitting the same across all cables of about 8200 ~ 9200 ohms. According to FSM it needs to be less than 30,000 i do see an improvement in spark plugs when cap is elevated. #6 still looks a little rich compared others. the reaming plugs look a lot better than prev pics. see attached n let me know what you think PLS i also did a dry compression test.

So i managed to take it for a spin while Dist Cap elevated. car ran extremely well compared to having a tight CAP. i was never able to engage turbo, and could not get above 30mph. i was able to boost, i see the turbo happy and i was able to hit 70 miles pretty quick. knowing my Z, id say im about %80 of it overall performance. running out to pick up a 9v Bat & Compression test tool

Dave, i forgot to mention that when i listened to the new injector #6 via stethoscope, it sounded exactly the same as the original injector#6. unlike the other five, it sounded very low, dim, the knocking was not as near as loud or as obvious as are the others were

Hey Dutch, i believe they are suppose to fire at diff times. at least that's what i saw when i had the rail partially out. im gonna try to loosen the screw at the tip near the belts and move the fuel rail far enough to put a paper and watch them spray. i did the obvious air leak check but any hints on deeper diags of airleak chk would be appreciated. im gonna look in to the compression test, but my understating is that comes in to identify lack of power. right now i cant figure out why spark plug 6 looks diff from others logically when i used harness# 6 on injector 5, the injector continued to operate. and when i used harness #5 on injector 6, it remained not working. this should rule out that harness is good and injector needs to be replaced. the new replacement appears to act the same.

Yeah, and what makes it more strange is that i checked for spark plugs Spark from the get go. i put the In-Line Ignition Tester on each one of them and watched.

stethoscope is what i used to figure out injector #6. then i did the harness swap to rule out the connectors/harness. injector 5 remained working. inject 6 remained not working. i cant imagine the new injector is DOA.

got it. so for sure the new inject#6 isnt participating at all. same behavior w orig injector. when i remove harness engine remains the same. i did swap harness connections around w #5. same results on injector #6. injector #5 also remained functional and when harness removed, engine would misbehave tmrw i will try to loosen fuel rail and watch the injectors spray. unless anyone has a better way to rule this out take care guys & tnx again!

Nice Z bud.. enjoy the party... the oil was due to loose valve cover screws. its all cleaned up now

Oh i see, ur referring to testing the actual terminal. i was referring to resistance on the actual injector between its positive and negative lead. all the other injectors were reading some Ohms (around 16) but not mister#6 gonna increase spark gap to at least .039 and see how it goes now that valves are set a lot tighter

According for FSM, gap needs to be .039-.043

the gap is about .035 or .036 on the new plug and bout .037 on the old the new injector is for turbo as per attached pic. my understanding that an injector is support to have about 16ohm of resistance. my orig#6 has zero. its as if things are shorted on the inside let me finish setting the valves back to a tighter spec (8 & 10) since that's how they were originally. hopefully that will at least clear up the Rich part yeah no kidding the idle is perfect. i left it running an hour while cleaning the garage. no missing or popping or chocking at all is there a specific injector link you folks recommend?

I hear u guys loud & clear. i've been keeping discipline. i was focusing on fuel/injector/air. All injectors had fuel flow and showed some resistance except#6 (no fuel , no resistance) Then the Dist CAP thing happened. I'm about done settings valves to .008 & .010 I cleaned up the spark plug area pretty nice. the plugs are NGK Platinum Alloy (BPR6EGP7085) Is there an injector brand you guys recommend?

@Captain Obvious, tnx for chipping in. I'm sure Dave is happy to read that. @s30 Driver....attached is how the Spark plugs look like. these are 2 week old plugs. Plug #6 received a new injector. I noticed the valve cover screws were not tight, which explains some of the oil spill. But what is the reason for the tip on Spark6 to be diff than the rest? Why is fuel not burning there? or is there no fuel getting there? Let me know guys if this should be in a diff subject. tnx again.

here are pics..im guessing mechanical ones..