1981 280zx will not start

[Eric280zx]

Hello guys! I'm new to this forum and recently new to the datsun world   I purchased a 1981 280zx datsun that has been sitting outside a barn for about 4-6 years and since it still had the engine I decided to see if I can get it running before I even consider swapping the same l28e or if I get lucky the l28et. The first things I did was:

1. change the oil,
2. replace the fuel filter 
3. flush tank and replace gasoline (regular)
4.  replaced battery with terminals
5. flush and replace coolant,
6. spark plug wires (all in correct firing order)
7. change ngk spark plugs (gaped .42 and added oil in each cylinder for lubrication)

I cranked it with no luck, I heard the oil pump running loudly but decided to use starter fluid. Once started fluid was sprayed and the engine was cranked and the engine started and was running on starter fluid so my next steps were:

1. clean injectors
2. clean fuel rail
3.  replace o rings and insulation 

I cranked it again without starter fluid and it only cranked but didnt start. So I did a compression test and numbers were 140, 145, 145, 140,145, 155 so compression is pretty good being that 180psi is like new. I removed the fuel return line and cranked the engine and gasoline came rushing out, I tested the spark and its a blue with white tint, engine sounds like it wants to start so timing is good (?), exhaust smells like gasoline and has pulses, and it still doesnt want to start. Each time i remove the spark plugs after attempting to start it, i can see a little wetness on the tip and it smells like gas. It started once with starter fluid but now it just doesnt want to even with it.  What do you guys think can be the problem? thank you!

[Dave WM]

Fuel pressure gauge before doing anything else, if you have not already study the FSM for what to look for on pressure.

Corrosion is a big problem on a lot of the connectors to the injectors and sensors, grounds and fuse links. Clean them all.

check for air leaks, EFI does not like unmetered air. Sensors tend to drift. The FSM has a good diagnosis section to point where to look.

I would listen for the injectors to be clicking.

 

Could be the injectors, you could pull them up, leave everything connected and have someone try starting, observe the spray.

What insulation are you referring to in 3?

 

 

[Eric280zx]

2 hours ago, Dave WM said:

Fuel pressure gauge before doing anything else, if you have not already study the FSM for what to look for on pressure.

Corrosion is a big problem on a lot of the connectors to the injectors and sensors, grounds and fuse links. Clean them all.

check for air leaks, EFI does not like unmetered air. Sensors tend to drift. The FSM has a good diagnosis section to point where to look.

I would listen for the injectors to be clicking.

 

Could be the injectors, you could pull them up, leave everything connected and have someone try starting, observe the spray.

What insulation are you referring to in 3?

 

 

What do you mean by the FSM? I have not checked the FSM on the l28e to check for fuel pressure but I thought it was getting enough fluid since it wasn't starting on starter fluid  

That is a really good idea, I'll do that! 

Injectors work for sure because when I cleaned them, I grounded them to a 12v battery and power and attached them to a pressurized hose with injector cleaner and they made the clicking noise and sprayed straight 

i have not sprayed them with the wiring harness though so I could give it a try 

injector insulation as like the bushing that go around it and on the head when you put Injectors in

 

thank you!

[Eric280zx]

Also, the spark plugs seem to be getting fuel on them 

[Dave WM]

FSM=factory service manual, gives you the correct pressures as well as a check list for common problems.

[Zed Head]

1 hour ago, Eric280zx said:

Also, the spark plugs seem to be getting fuel on them 

Might be flooding due to disconnected or broken coolant temperature sensor.  And somebody parked it beside the barn for a reason.

The 1980 EFI Manual is probably about the same for 1981.  Might use it to at least get familiar with the parts.

http://www.classiczcars.com/files/category/14-280zx/

http://www.classiczcars.com/files/category/4-manuals/  1980 "EFI Book"

[Eric280zx]

If it will help to determine the problem, i am also missing two fuses on the interior panel of the car, it is # 7 and #8 and haven't determined what they are for. I still have to clean any corroded wires, sensor plugs, check for air leaks with the EFI, check the coolant sensor, and check fuel pressure. I'll post up my results after doing all this 

[Eric280zx]

So I did everything with still no luck. I did check the oil and I noticed it's wayyy over the high level and it smells like gas. I took a quart of oil out and it's more of a liquid substance now with a smell of gas. I think my problem is a leaking fuel Injector. What do you guys think? If so, is it the injector or harness? 

[siteunseen]

I would take a screwdriver handle and tap on the injectors to free up a stuck magnet. I bought a motor with a bad carbeurator and the oil was half gasoline from the stuck carb float dumping all that fuel on the head then it drops down the front cover/timing chain hole straight into the oil pan. The plus side, if you could say that was the gas had washed the head/valve train to look like brand new. But it's not good especially on the valve seals.

You can get a piece of hose to use as a stethoscope to hear the injectors clicking. Whichever one doesn't click is stuck, tap it until it starts clicking hopefully or you may have to replace it.

[Dave WM]

don't forget to check the cold start injector.  Pull it out of the manifold and look to see if its leaking, in warm weather (over 70f) it should not spray, and it should only spray when the key is in the "Start" position even when its cold. Often times people goof up the bullet connections for the temp sensor for the EFI and the cold start thermotime swtich, make sure they are correct.

[siteunseen]

Good call! I forgot about the cold start valve. Some folks don't even have one. Depends on where you live and how cold it gets. 

[Zed Head]

1 hour ago, Eric280zx said:

So I did everything with still no luck. I did check the oil and I noticed it's wayyy over the high level and it smells like gas. I took a quart of oil out and it's more of a liquid substance now with a smell of gas. I think my problem is a leaking fuel Injector. What do you guys think? If so, is it the injector or harness? 

The injectors get power as soon as you turn the key On.  So any short to ground on the wires going back to the ECU would open them.  A pinched or abraded wire for example.  But a short should show up in your testing at the ECU, as a voltage drop, less than battery voltage measured at the injector pins.  You might also hear them click when your turn the key on although the BCDD clicks also.

The CSV should only get power when the key is at Start.  So it's possible that it would flood the engine, but the odds of pumping a quart of gas in to the engine through shorted injectors, by sitting with the key On, thinking, seems more likely.

I filled a chevy crankcase with gasoline after I put a friend's carb on the car and tried to start it.  Turns out he had got it from someone else and they had removed the float valve.