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Help! 78 280z


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My car cranks, and it now has spark. When I spray lighter fluid after starting the car it roars, but if I push the gas nothing happens. I can get it to idle for a minute occasionally, usually doesnt start though. I am pretty sure this means it is not getting fuel

 

I spent a lot of time to replace spark plugs, ignition coil, distributor cap, crank sensor(I that is what its called) underneath distrubor cap as well.

 

I took off the hose from the fuel filter that goes to the engine (while off), and the fuel powerfully created a geyser into my face. Should I try taking it off and then crank the engine to see if its getting fuel?

 

 

How should I proceed?

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My car cranks, and it now has spark. When I spray lighter fluid after starting the car it roars, but if I push the gas nothing happens. I can get it to idle for a minute occasionally, usually doesnt start though. I am pretty sure this means it is not getting fuel

 

I spent a lot of time to replace spark plugs, ignition coil, distributor cap, crank sensor(I that is what its called) underneath distrubor cap as well.

 

I took off the hose from the fuel filter that goes to the engine (while off), and the fuel powerfully created a geyser into my face. Should I try taking it off and then crank the engine to see if its getting fuel?

 

 

How should I proceed?

 

Bwahahahaha! I did that myself a little while ago. Residual pressure stays in the fuel system for a time. One way to remove it (sans geyser-to-face) is explained in the FSM. What you do is take two wires from the battery and connect them to the two contact points on your cold start valve (after removing its connector). I actually found it was easier to take a 9 volt battery with two paper clips attached to the contacts. When you touch it, listen for a *click*, which should be your CSV opening. Thing is, this will dump fuel into your intake manifold, so I'd suggest pulling the injector side of it out of the manifold first. If I'm not explaining this clear enough, both the Haynes manual and the FSM and EFI bible have decent pictures of the process.

 

As for your other problems, I'd suggest finding and cleaning EVERY SINGLE connector and ground in your fuel injection wiring harness. Corrosion will inhibit the continuity of your circuits. Maybe your problem is that the fuel isn't leaving the injectors then? Before you go out and buy new ones (usually $250 and up for a set), run the tests described in the EFI bible and the fuel injection section of the FSM (Factory Service Manual or Full Shop Manual). You can download both from the internet, in fact if you search for it here you will easily find a link to it. Electrical issues with this car suck, and you will find no infrequency of them.

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forgot to mention...

 

 

it has been parked for 13 years...

 

I dont mind if it squirts up, just figured i would mention that. It squirts up once and then dies down. We ran with it off just a little while ago, and a little bit of fuel came up. Should I try running it and then pushing on the gas? do I need to start the car for pumping the gas pedal to help?

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Alright, we pulled off the hose that goes from the fuel filter to the engine, and it took about 8 seconds (while cranking the engine) for any fuel to come out of the filter.

 

When it was all hooked up, the engine wouldnt start unless we sprayed starting fluid into the air intake behind the air filter.

 

My father thinks that the fuel injectors aren't opening for some reason...

 

I have not taken off a fuel injector yet. I will see if I can do that later.

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I talked to my favorite guy at schucks, he told me it would be easier to take out the spark plugs and crank the engine then to pull of fuel injectors, and if vapor comes out of the piston then we know it is working.

 

He told me to relieve pressure in the fuel system (following steps in my chilton repair manual) to do that. Than I put the key into the on position while someone in the back is listening to the fuel pump.

 

I mentioned to him that the flap over the oxygen sensor module (i think thats what is called) with the air intake opens up, so I duct taped it shut for the time being. He told me I should use silicon sealant on it because if air got into that then the wrong amount of gas would spray and that would lead to the problem I have.

 

Lastly I told him about a misaligned mark on the distributor, mentioning that I am not sure if I should turn it into place. I will use a timing light to calibrate it.

 

I am putting in some isoheet into the fuel system to get rid of any mositure that was built up, I changed the gasoline because it was parked for 13 years so I figured the iso-heet is something else I should do.

 

So what do you guys think of that plan?

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I don't think you can edit a post after a certian amount of time.

as for your AFM (the proper name for it)

I don't have a cover on it. AIR won't hurt it, but WATER will. it'll corrode the contacts and screw it up. and since you're in Washington, I suggest you do seal it up (I'm in AZ, corrosion doesn't exist >_>)

 

get yourself a 9v battery and an injector plug, and see if you hear the injectors clicking. if you hear a click when you plug your battery in, it's opening. I would change your fuel filter too. Also, take the hose off the input for your fuel pump, and clean the screen out. (it doesn't hurt to put a Fram G3 filter in there too, incase you have a dirty tank like I do)

change out your main fuel filter if you haven't already.

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fuel injection is supposed to have a ton of pressure... a lot more than carburetors lol. I have worked with carbureted before, not fuel injected so I know that the problem is probably before the fuel filter. When I took the hose off the fuel filter, it took about 8 seconds for fuel to flow out, when its supposed to immediately shoot out fuel. So before investing in a fuel pump, I will be checking out the line between the tank and the pump tomorrow, along with checking out the rest of the fuel line.

 

I know that sometimes there is a fuel filter in the gas tank, does my car have that?

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I never thought of checking for a kink! I wonder how that would happen lol.

 

Should I try to take the line out and put water through it to check to see how well the flow is?

 

yeah I haven't had time for those projects I put on for the next day, yesterday I checked for prices for fuel pumps at various part stores, 150$ from the store and 100 from ebay.

 

I will be checking the fuel line and clearing stuff out to make sure the path is clear soon.

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have you put a fuel pressure gage on the fuel line at the engine. Put it in line with the supple and the eng with a "T" fitting. See what it is pushing to and returning.. Then pinch the line on the eng side of the gage while

cranking to see the max pressure output from the pump,.. keep pinching and stop cranking see if there is a drop in pressure If so the check valve is leaking back.. With the engine turning over use a long screwdriver placed on the injectors and handle to your ear you should be able to hear it clicking check all injectors.. If not you have elec problems

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there's no filter inside the gas tank. I would check the fuel lines though. My Z actually had a nasty nasty kink in the fuel line that would only allow enough fuel to let the car idle and run REALLY lean (it would rev fine, but put any load on it and it would get really pissed off)

 

what do u mean a nasty kink? as in the hose was kinked(sharp bend) somehow, or there was some serious buildup inside the hardline? im kinda having the same problem with reving and definetly shes gettin some pms when revving under load...my 280z had been sitting since 1991, and i swapped my 1983 280zx motor into it. not to thread jack...but about the FPR. i have a pressure guage on a t-fitting between the main filter and the manifold. with the vacuum hose on the FPR attached to the manifold, my fuel pressure will read something like 26psi. when i romp on the gas itll go up to about 30psi, then immediately back down to ~26. if i take the hose loose from the manifold and just have it open to atmosphere, it will read exactly 36psi all the time, romping gas or idling. is my FPRs diaphram gone? also, i know i need to clean all electrical connections and do efi bible diagnostics as i have not done that yet. im getting some nasty frontfire when i rev the motor. its only on initial rev, between like 2000-2500rpm. i retarded the timing and frontfire got worse, advanced a timing a little and it got slightly better. ive checked my intake vacuum and its at 20mmHg, and i have sprayed carb cleaner on all possible places for vacuum leaks that i can think of, with no change of rpm. so i dont think i have a leak. any ideas besides the obvious(efi bible/contact cleaning)?

 

emaster, u may run into a problem similar to this once u get over the current problem...so this is sorta relevant to your initial post. sorry bro!!! i owe ya a brew! lol

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i had a similar problem with my 280zx that was sitting for 7 years when i got it...what i had to do:

take off the tank and clean and seal it with por-15 take off the fuel pump and clean it out(because when the junky fuel went through it most of it probably got stuck)...i cleaned mine with air pressure but thats probably not the best way...replace the fuel pressure regulator(because i can garantee it will be clogged) mine wouldnt idol and was creating back pressure($50 at auto zone) and take the injectors off and soak them in fuel injection cleaner for a while....(most of mine were stuck because of the gunky gas) after i did all that i never had a problem with getting fuel again....hope this helps

 

p.s. the fuel pump has a very distintive noise and when u turn the key to accesory you should hear it very distictly and smooth if it isnt either then it is clogged

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I checked the the line between the tank and the fuel pump, and followed the line to the fuel filter. Everything checked out fine, and before I put in some alcohol type stuff that they told me to put in at schucks. That stuff is supposed to take out any moisture and they said it would also clean out anything in the lines as well. That was a while ago and it still isnt working. I ordered a fuel pump online which will arrive in a few days and I will replace that and let you know how that goes.

 

After that I need to fix the brakes, meaning replacing all the non-metal lines. Does anyone know what type of lines the 280z uses because its not all metal for the brakes.

 

thanks guys

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