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280zxt timing problem


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i have a l28et in my 240z. i have it running but not how i would like it to be. i have a timing light and i tried to set the timing to 20* but when i rotate the dizzy all the way over it only goes to 9*. on my old 240z, you could just pull the dizzy out and rotate it a notch or two over, but with my 280zxt dizzy the shaft can only fit in one way. what's the problem here? it seems to be running too rich and it drenches my spark plugs with gas when i try to start it. i have to pull them out and clean them. any help would be appreciated. thanks

jesse

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The thing that happens most often with the rich problem is that one of the yellow wires should only get 12 volts during cranking, it provides a cranking enrichment. When I first did the swap I had it hooked to 12 volts all the time and it ran so rich is would choke you in the garage with the door open.

 

the plug #2 start signal as shown below is what I am referring to:

 

The wires are as follows:

 

Plug 1= BR 12v power source. Positive

 

G 12v power source. Positive

 

Plug 2=Y start signal (+)

GL ground for inhibitor switch

YW speed sensor (not necessary)

Y A/C signal (+)

YW coil (-) (must use ignitor)

B fuel pump ground if using modulator

 

Plug 3=LR fuel pump relay

G ignition .signal (+) for air regulator

W not used

Y not used

BW ignition signal (+)

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If the most you can advance it by the adjustment at the base of the distributor is 9 BTDC, then your oil pump spindle was inserted one tooth off. When I advanced mine all the way, it was at 32. I was able to bring it back slightly and set it at 24 where it should be.

 

You will need to set the engine at zero deg which should put the #1 piston at TDC and the compression stroke. Remove the front sway bar, drop the oil pump (remove the dizzy too) and line up the dot on the oil pump spindle with the center of the curved indent in the oil pump. Insert the oil pump straight up. then reinstall the dizzy

 

From my experience with 4 and 6 cylinder L-series they are all set up like this. I have not known a distributor that could be removed and re-clocked from the top. they all have a bolt at the base to loosen and a small amount of adjustment but not being reclocked.

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Do you have a link to a post with info on this? My turbo engine is running and I wired one of these wires up but maybe the ECU isn't getting the correct signal for retarding the timing or something. My car's power just chokes out under boost.

The thing that happens most often with the rich problem is that one of the yellow wires should only get 12 volts during cranking' date=' it provides a cranking enrichment. When I first did the swap I had it hooked to 12 volts all the time and it ran so rich is would choke you in the garage with the door open.

 

the plug #2 start signal as shown below is what I am referring to:

The wires are as follows:

 

Plug 1= BR 12v power source. Positive

 

G 12v power source. Positive

 

Plug 2=Y start signal (+)

GL ground for inhibitor switch

YW speed sensor (not necessary)

Y A/C signal (+)

YW coil (-) (must use ignitor)

B fuel pump ground if using modulator

 

Plug 3=LR fuel pump relay

G ignition .signal (+) for air regulator

W not used

Y not used

BW ignition signal (+)

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That was in the ultimate turbo FAQ, it also has a better description in there:

 

fuel and spark only.

 

 

(by the battery)

Fusible link box wiring:

Plug 1= BR 12v power source. Positive

G 12v power source. Positive

these two wires are the only ones needed from that big ol box, you can cut the other ones off to simplify.

 

(found right next to ecu pins)

Plug 2=Y start signal (+) --------connected this to the spade connection on the starter-have disconnected it and while the car will still start, it starts faster with it hooked up for that oem feel.

 

GL ground for inhibitor switch-----not needed.

YW speed sensor (not necessary) -----not needed.

Y A/C signal (+)

YW coil (-) (must use ignitor) -------goes to y/w on ignitor or ignitor - if you dont have the connector for the ignitor. other pin on ignitor goes to the ignition switch, you can use the existing b/w wire or other colored wire that is already there to supply the other side of the ignitor.

B fuel pump ground if using modulator-----not needed.

 

 

By the Battery

Plug 3=LR fuel pump relay ------- trigger wire for bosch relay ( substituted for nissan relay for easier replacement and standard relay wiring logic, in my car i used this to trigger another relay with a 10ga hotwire, L/R is what makes the fuel pump cycle for five seconds when you turn the key on, and is good to use because if the car stalls the pump shuts off after 5 seconds. L/R=blue/red,

G ignition .signal (+) for air regulator ----not needed.cut

W not used -----cut

Y not used ------cut

BW ignition signal (+): This wire is found connected to the green efi relay, cut this and wire it to on/start of ignition key switch.

 

now BOOST.

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ok, i checked the yellow wire in plug 2. it is connected to a 12v power source during cranking only. is the other yellow wire in plug two (Y A/C signal (+)) refering to air coditioning? if not what is it and do i need it? my car isn't actually running that rich, it's just drenching the plugs before the car starts. then i have to clean them and try again. it takes a while to start and definately doesnt have an oem feel. sometimes i have to turn the key on and off about 5 times priming the engine before i even have any sign of gas entering the combustion chamber than all of a sudden its too much. once it is started it isn't rich. is it because my timing is so retarded and the plugs are getting covered with gas before they have a chance to fire? and about the timing. i don't think the engine has ever been rebuilt so how could the oil pump spindle pin be in one tooth off. i think its stock. how do i set the engine to zero deg? thanks for helping me figure this out.

jesse

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oh, so you put a used engine in your car without even installing a new timing chain. Well, you never know who might have messed with it in the past... so it could be off

 

try disconnecting the battery and re-connecting. That fixed a rich starting problem I had. weird, huh?

 

turn the front crank with a stocket to get it exactly at TDC. Move the mark on the front crank pully to the Zero on the timing plate.

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That was in the ultimate turbo FAQ, it also has a better description in there:

ok thanks. I went over it and I had connected everything correct the first time. I guess I have other issues. Not really sure what the problem is... its hard to search the archives not knowing what is going on.

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ok, i did what you said. dropped the oil pump and spun it over one notch. but it was too far. 20* was still out of its range. so i filed down the bolt holes in the distributor so i could turn it more. now i'm at 16*. so its working. i just need to do a little more filing and i'm there. is there anything wrong with doing this?

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ok, i did what you said. dropped the oil pump and spun it over one notch. but it was too far. 20* was still out of its range. so i filed down the bolt holes in the distributor so i could turn it more. now i'm at 16*. so its working. i just need to do a little more filing and i'm there. is there anything wrong with doing this?

 

Boy, all I can say is that I had a 260z engine that the dizzy would not lign up correctly and it turned out that the timing chain was not installed correctly, so make sure that you know the timing chain is correct. I monkey'd around and slotted the dizzy so the timing would be correct and then fired it up and the valves where hitting the pistons. That was back in the beginning before I learned to check my basics when something doesn't lign up. It bent one valve.

 

Bleachzee already said the timing could be off on the chain, did you have a chance to check it?

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ok, i took the valve cover off and checked timing chain on the cam sprocket. #1 on the sprocket lines up with the bright link. so it's good. the valves can only hit the pistons if the chain is not on the correct tooth, right? and i took the oil pump off and moved it over one tooth. it said in the haynes manual that you're supposed to line up the dot on the spindle with the hole on the oil pump. that's where it was when i took it off. now it is one tooth away. but it seems to work. my timing is at 21* with the distributor right in the middle. will this cause any problems?

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the factory service manual says set it at 24 deg +/- 3 so 21 works. :D

 

I'm still having issues. I fixed some boost leaks, set my timing at 24... still boosts great but pops (intake) now and then and just bogs under full boost.

 

I assembled my engine and it has a new chain that was installed correct. The dizzy is close to centered at 24 deg so the oil pump spindle was in correct.

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ok it seems to be running really good now. when it's warm and been running recently it starts right up. after driving it again i readjusted the timing to 23* because it runs best there. thanks for the help, i would have never figured it out.

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  • 1 month later...

same problem im having with my 83 280zx turbo 2+2.. hears htep roblem the guy befopre me took off the valve cover and tried to set the timing him self.. i watched him try it.. he turned the crank with a 19mm wrench he got it to TDC right.. but he tried to set the iggy timing to number 6 spark plug .. the car started but would onyl run with the gas petal all the way to the floor... ..... so u set the cam to TDC and check to see if the pistion is all the way up right ? then u set the dissy timing to what numebr spark plug ? thats were im messing up at... ?

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  • 4 weeks later...
The thing that happens most often with the rich problem is that one of the yellow wires should only get 12 volts during cranking' date=' it provides a cranking enrichment. When I first did the swap I had it hooked to 12 volts all the time and it ran so rich is would choke you in the garage with the door open.

 

the plug #2 start signal as shown below is what I am referring to:[/quote']

 

Board-

I have finally joined this brain trust to gain some insight on what exactly I am doing wrong....or should I say my Z's attitude problem..

 

I am a story teller-so for the sake of time and (yawn..) typing fatigue..I will give you all some insight on my plight for the last few years..hopes someone can give me direction.:willy_nil

 

Blew the engine when I overheated on the freeway at 100+ one day....radiator hose blew out and warped the head...etc..etc..etc

 

The car sat for a few years at home until I decided to bring it back to life. Had a shop (who did not SPECIALIZE in Z cars ) rebuild the engine for me...thats when the problems started...:banghead:

 

In the course of time-I discovered quite a bit about EFI and proper bonding methods in the engine compartment. Much heartache was experienced until the electrical bonding issue was resolved. The mechanic failed to re connect/attach some bonding straps to the engine, frame and body. I never realized how important bonding was until this time....my research has shown that these issues MUST be resolved to insure a relatively trouble free ignition system....

 

My 1981 ZX Turbo has the crank angle sensor ...geez-I wonder why Nissan did not continue such a fantastic idea into 1982 and beyond models...:flamedevi

 

When the engine was rebuilt-the mechanic did not set the timing correctly when he re assembled the Distrib and oil pump..ran like CR*P...he finally retimed it-but it always ran rich. I have passed smog after it was rebuilt..but it continues to run rich.:icon13:

 

Now-it has a tendency to backfire/pop when trying to accelerate (not all the time)

 

I found the cold idle switch wires in bad shape (frayed) so I re terminated them to the switch. Has anyone seen a cold idle switch fail? How to test to be sure it is good? MAF was replaced (smog guy said mine was wacked out from adjustment)..From what I have read-RICHNESS is determined by ECU and MAF...what sensor could cause a rich condition?

 

I wanted to get all the points out in hopes of advice from you all...if the fuel pressure regulator was bad-would not loss of power also be evident?

 

I have a fuel rail and TURBO injectors to install in this vehicle...I had some leaky injectors when I got the car a number of years back-and replaced them with AUTO ZONE units..and have since found that these are NOT hi flow units that were orignial in my Z from the factory...If I put the fuel rail on and injectors..can I use the stock fuel pressure regulator?

 

If you have read this far-thanks! I really need some direction to resolve these woes...:cheers:

 

David (Newbie member)

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Maybe start up your own thread so for a better response.

 

I have moved on to another ZZZ board-and I have found much help and direction there....first post and I got 7 hits with solid info....I am on a mission to resolve this-quick responses to posts is what i need now...--

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