Fuel Rail Question/cant get it started

[jimmytx]

82 280zx. Ran nicely until it didnt, then I replaced the fuel pump. The gas was bad (dark, smelled of varnish, sat for 10 + years), I ran it with the bad gas for a while (10 mins at a time, around the block once), then it just stopped. Pumped out 95% of the remaining gas just north of the fuel filter, then replaced the fuel filter. Put in new gas. Verified it has spark by pulling a spark plug. Pulled off valve cover to try to inspect timing belt, discovered it has a timing chain. Put valve cover back on. Pulled the injector closest to the firewall, noted the plastic ring that serves as some kind of over-grown O ring (I guess) is broken, verified some gas is squirting out, replaced injector. Removed rubber air intake hose upstream of butterfly air plenum (not sure the correct term..the device that moves when the gas pedal is depressed), squirted lots of starter fluid down it's throat, no fire. I thought that would have ruled out the lack of fuel. So if my thinking is correct, I have a fuel source, spark and compression, yet the thing refuses to fire up, or even hiccup and backfire. Spark plugs are not wet. Does there need to be sufficient vacuum in the intake manifold and am I disturbing this by having the rubber intake hose (from air cleaner) disconnected, therefore breaking the sucking of the ether down the pistons? Should I concentrate on replacing that broken o ring on cyledar #6 then hook the connecting air intake rubber tubing? Im thinking even if the injectors are clogged, squirting the starter fluid directly into the plenum should provide a fuel source. Fuel + spark + compression SHOULD result in something!!

Thanks everyone.

Austin is great in April, wish I were driving around in my Z.

Jim.

[ZXR616]

Are you removing the rubber boot before or after the AFM (air flow meter)? If you removed the boot after the AFM, the "brain" does not know there is any air going to the throttle body/intake so no run-run.

Did you get ALL of the bad gas out of the fuel rail? Easy way to clear the rail is to remove the return line, stick it in a container, and turn on the fuel pump. That will also show if you have a blockage in the fuel line, rail, filter, return line. You will have a small residual amount of bad gas at the injectors, but that will clear quickly.

Check your fuel pressure.

Unfortunately, the lesson here is "Do NOT run an injected engine on bad gas"!

It'll also kill the catalytic converter.

[Zed Head]

How did the spark look? Blue or orange and weak? And when you say starter fluid do you actually mean starter fluid or something similar like WD-40 or brake cleaner (people do things...)?

Read the Engine Fuel chapter in the FSM. Those overgrown o-rings and other stuff will make more sense.

It should run with starter fluid if you have spark and nothing major went wrong. How did the plug that you pulled look? You might have just re-fouled it with bad gas when you re-installed it.

[jimmytx]

The spark was bright white. The starter fluid is starter fluid, though somebody told me it aint what it used to be. I was squirting downstream of the Air Flow Meter, hooked it back up. Cant quite get the can of starter fluid in the limited space now, will look for a shorter can, or get some kind of straw attached to it. Did check the return line, gas is flowing freely, cleared it. Still nothing. Will persue a pressure checking gauge. Pep Boys dosent have it. Any suggestions?

[Zed Head]

Hook everything back up, remove a vacuum line from the top of the intake manifold and squirt some in that way. The easiest is the tiny one that supplies the heater valve control bottle. That way you'll have fluid in the intake manifold plenum so any air passing by will have to pick some up.

Be aware also, that all openings to the engine have to be sealed. Oil filler cap, dip stick tube, all vacuum hoses, valve cover bolted down, etc. The intake system is connected to the PCV system so any leaks in to the engine will be a leak in to the air intake.

[EuroDat]

Will persue a pressure checking gauge. Pep Boys dosent have it. Any suggestions?

You need it the at least fire on the starter fluid before moving on. If it doesn't do that than its not fuel related. Once you have it firing on starter fluid you can do a pressure test. Any pressure gauge will do as long as it can read up to 60psi and a fitting that is handy to connect into your fuel line. See post #124 in this thread http://www.classiczcars.com/forums/open-s30-z-discussions/50066-280z-full-restore-5-months-hopefully-2.html for an example.

Chas

[jimmytx]

OK, I wanted to attach some short movies showing the spark plug against the block, squirting the starter fluid down into the intake manifold, shocking the heck out myself, etc. The spark seems weak and it took a little cranking the first time before any spark came on at all. The car ALMOST started when I had one plug out (you can hear it). When I replaced the plug and shot the starter fluid down the hole it didnt fire at all, almost like it was flooding. Maybe I have an electrical issue after all. Coil, module, I dont know. Somebody smarter than me is going to have to call this one.

And the format of the movies are wrong. Anybody know what this site finds acceptble? Ill try to find some software to convert the files.

Thanks, Jim.

[Zed Head]

Sounding like a bad ignition module, possibly. You could do the electrical checks in the FSM. Some times the modules are bad enough that the tests will show it.

el chapter, page EL-28. The testing procedures are so old though that the module test requires looking for needle waver on a voltmeter. Still worth going through, you could have a bad pickup coil, bad grounds, etc.

http://www.nicoclub.com/FSM/280z/1982/1982%20280zx%20FSM/el.pdf

[Darrel]

check the wiring at the head temp sensor, if it has the head temp sensor. between 5 and 6 spark plug on the head.

[siteunseen]

All the videos I see are posted on youtube first. Then put the youtube link on here.

[jimmytx]

Replaced the ignition module (on the distributor), and the distributor cap. Temp sensor on the head is intact. Just noticed now that the spark is pretty yellow. Think Ill order a pickup coil and throw it on there.

[jimmytx]

Borrowed a compression tester from AZ, 0-5 psi all cylinders. Will get another gauge and verify results tomorrow. If confirmed there is a guy up the road that has a L28 for sale cheap. Stay tuned.