No-Z-Idle

Greetings everyone,

I am working on a sad 1980 Anniversary Edition 280ZX that was only driven 11 miles somewhere in the last 12 years. (it has more than 11 miles on it, just 11 were in the last 12 years)

A friend of mine was forced to sell it 12 years ago, after Z Specialties installed a better cam and other goodies..

A few months ago he noticed it at a tire shop (in the back) and inquired as to it's availability...

He was told it was for sale, and at only $200... where my friend pulled out $100 in cash and was promptly handed the old title.... with his signature already on it...

In passing through 2 people's hands in 12 years, nobody bothered to transfer title out of my friend's name.

Why so cheap? It didn't start (bad fuel for sure), and it is now rusted very bad...

The other day I took a quick look at it and noticed no power to the fuel pump... which I quickly rectified (for testing purposes by running a separate wire) ... sputter sputter...

OK, apparently we have ignition...

Next quick check? about 2 ounces of gasoline poured in the middle of the air cleaner... we have ignition... and more importantly, we have working injectors for nearly 30 seconds... revs perfectly between fast idle and 3500rpm (best guess since the dash is dead other than the fuel gauge)

Again, again, and once more... 30-45 seconds of normal power/smoothness then it dies (feathering the throttle helps sometimes leading me to believe the TPS may be bad now)

One note: It does NOT idle at all, not even close...

Somehow it seems to run above idle decently, for only some period less than 60 seconds... and it is repeatable as often as someone gives it a shot of gas to get it to initially fire.

engine fluids have been changed, new battery, air meter moves (no guarantee it's signals are good though)


The clutch master and or slave are a total loss but brakes were full up and operate.... something to worry about later....

Our first interest is in regaining idle and normal engine operation...

And for those who care... #546 of the Anniversary Edition... the number is still on the dash... and it is the red and black one...


OK: Any ideas where to go from here?

I am no Z mechanic (Domestics for me), but my friend announced $50 for the first one to get it to run longer than 30 seconds.... I couldn't pass that up.

Obviously I won that... but I would like to do more for my mechanically disinclined friend... just to be a good buddy...

For what it's worth, I did go to school for auto mechanics, and I did later work for a busy shop doing much more than grease monkey jobs... eg. I do recognize the difference between an injector and a temperature sensor, etc.

It's been years now since then, as I have moved on to become an engineer for a television station, so I am a little rusty on Z car specifics..

I would like to know how to check the ECU / codes..

Tomorrow I will be unplugging and replugging in EVERYTHING to confirm no loss of connection due to corrosion (anything visibly corroded will be cleaned and greased up with a silicone dielectric grease)

I am bothered by the lack of instrumentation inside... and expect it to be corrosion somewhere....

On a side note..... we will be looking for doors and rear quarter panels to replace the rusted ones the car has now... Anyone near Olympia, WA (USA) with sheetmetal parts?

Another side note: I closed and locked the top glass and poured a bucket of water over them and could find no leaks even minutes later.. the inside is nice still.

Anyway, A little help would be nice figuring where the ECU is not functioning correctly...

Any questions will be answered as I have time ( I am also house sitting here as my friend had to take a trip to rescue his wife... and they raise Miniature Pinchers and Chihuahuas here (my hands are full much of the day caring for them))

Thank You for the help,
Aaron

NismoPick

Welcome to ZDriver!

#1... Did you change out the gas? 12+ year old gas will be thick goo in the tank... and won't burn very effectively... and probably isn't good on the fuel pump, filter, or injectors.

#2... The 280zx ecu doesn't have diagnostic codes... this is a simple EFI system.

#3... If you haven't yet, buy a Haynes manual.

SHADY280

do a full tune up just like any car that has been sitting that long would need. plugs wires cap rotor fuel filter and clean the corroded connections in the engine bay. check all fuses as the dash doesnt work, so there may be some missing, or connections unplugged for diagnostic from the last guy. also get digital camera and post pix up on here using photobucket or simmilar site for hosting!!

KasbeKZ

true that. tune up and connections as stated. there are ways to test most engine sensors too, so you may use the haynes to test those and find if one is bad. the quarter panels.... is this not a unibody car? i think you will be needing to cut out the rust and weld in some new metal

lifegrddude

If it's been sitting for 12 years, change all the vacuum and fuel lines. Guaranteed those vacuum lines aren't worth a hoot. The fuel injectors could probably stand to be cleaned as well. Install a new fuel filter, and see if that helps with the fuel delivery issue. Good luck with the Z.

duowing

I was going to say probably a vacuum leak somewhere. As I've dealt with a big vacuum leak which may the car not idle, but would rev up.

CWHammer

If it were me and I had received the car for that little I would be pulling the driveline out and going through EVERYTHING. As any car sits condensation will build in the cylinders, heads, etc... That means moisture and the potential for rust. For the cost of a gasket set you can have the peace of mind in KNOWING that the engine, trans, diff are rust free and well lubed with fresh liquids. All of the rubber (everything) bushings are probably shot. The worst thing you can do to a car is let it sit for a decade with no attention to anything. Sorry for the doom and gloom but be prepared for the worst but also the best. The most fun I've had in years has come from driving my Z after putting exhaustive hours into it. To do so with red and black anniversary edition would make it that much sweeter. Never give up and good luck. I wish I could be as lucky.

No-Z-Idle

Thank you to everyone!

Now, mostly in order:

Vacuum hoses are all decent (new after Z Specialist did the cam and injectors, and the humidity here in Washington State has kept the lines reasonably well preserved.)

RE: The same moisture that has preserved the integrity of the rubber has also caused the thin body metal used to rust, more in some areas than others

Fuel delivery is almost definitely the injectors working briefly, then the EFI shutting down because of either a bad connection to sensors or another similar kind of problem... the FPR is regulating pressure fine, 40PSI (or close to that with the cheap EFI pressure gauge I have) with just power to the pump (bypassed computer) and it drops to between 35-38PSI while running with vacuum normal.

Speaking of vacuum, the canister takes quite a while to leak down, normal if I recall how it lasted 12 years ago...

Problems I see are the connector for engine crank angle is not secure, tps connector ify, and without further testing - No tach or gauges, except voltage and gas.

2 of the injector harness connectors are missing the metal clips, but seem to all work fine for as long as a minute (closer to 55 seconds)

I will concentrate on getting the electrical connectors all solid before I do anything else.

I was just wondering if there were "common woes" for such a car, but I see none in the responses...

I will post again when I clear up more of the problems.

Oh, yeah, regarding replacing quarter panels, absolutely! Definately it is a cut and weld job here.. but that is going to be left to the body shop.. nobody here has the equipment or training for such surgery :-)

Again, Thanks to everyone,
Aaron

No-Z-Idle

I just took pictures all around.. there's some ugly passenger side metal underneath..

I will post the pictures to one of my websites tonight.

If you click all the way through all of the pictures are 6MP.

And I will stitch together some of them to give a detailed view of the engine compartment.

I will post the URL when pictures are up.

Aaron

Niku-Sama

you know if you resize them smaller the pics will be better detailed.
i can just forsee the huger than monitor fuzzy pictures ahead. i have a low -ish native res on my monitor so it makes it 10 times worse. 1366x768, but its a 32" tv at the same time

NismoPick

No-Z-Idle... did you drain the gas tank??? Hopefully you're not trying to run it on 12 year old gas.

CWHammer

Where are you checking the fuel pressure? Before or after the filter? Have you checked the head temp sensor connection? Common problem with starting/running issues. Make sure you drain all of the sludge from the tank. Not only will the gas be nothing more than paint thinner but there is prbably some significant sediment in there too. Condensation can still happen even though the tank is sealed and cause rust to form. I had the same problem with my '83 that had sat in a barn for several years. Took out the fuel pump and the filter.

Bleach

wow, red and black 10th? those are even more rare.

Z Specialties is a Washington state company. Are you in Washington?

looks like there are at least 2 Red/Black 10th Z's in Washington.

No-Z-Idle

Niku..

Actually all of my pictures are very detailed as is, just large, but my album software starts viewers off in large thumbnail mode (280x160 pixels or close depending on picture aspect ratio) then clicked go to whatever size fits your bowser minus the site borders and buttons... then clicked again: Opens either a New Browser window, or a new tab depending on what browser or addons you have.. either way, click on the picture again and it goes back to the middle size closing whichever mode of display your browser displayed at native picture size.

Besides being a TV Station Engineer, I am also a computer professional on the side, so I am up on my optical gadgetry..

Don't get me wrong, I haven't gone overboard.. that is reserved for some truly dedicated car enthusiast/photographers. :-)

I think the picture of the TPS and it's plug is the worst I took, I will probably focus restore it a little and shrink it enough to make it a 1:1 representation of the actual hardware.. if I post it at all.

I took a picture of it by itself because I knew it was missing the metal spring clip, like 2 of the injectors (#3 and #6 I believe)

Regarding the rest of the concerns, tank was not only drained, but also flushed well, drying between flushes.....

Filter was disconnected before the pump was used to flush the lines.

The pressure is taken after the filter, but before the regulator, though of course there is a loop in the rail, so I see what the engine sees.

After about a week and a half pressure is not bleeding below 27Lbs and that is with no clamp between the meter and fuel rail inlet... it's a tight fit with a new gauge and tube.

Those who asked, remember, electrical problem... the car will start and immediately can be burped or run up in RPMs for a total of about 50-55 seconds EXACTLY as if it had no troubles at all...

I do believe this means (with pump left powered continuously via a temporary direct battery connection, and yes, it is more than large enough at 10 guage) that the car runs during the cold start phase fine, then fails to switch over to normal mode in the EFI, possibly due to a bad connection or something somewhere, or at least that is my take from my electronics training.

I could be wrong, which is why I am here for help.

Back to it running initially... In the initial 50 seconds after start you can rev the engine several times (to any safe level below redline) and it never acts starved... it is very smooth during this period, with no lean popping or backfiring... this leads me to believe the fuel system is fine, and the electrical is where the problem lies...

After it dies there is about a 50/50 chance of it starting by only turning the key... otherwise of the remaining 50% chance, you may either floor it and get it to start, or feathering it... that is perceptibly 25% overall with the only other way to get fire being to spritz some gas down the air inlet (Enrichment)

(no, i did't even spend an hour to determine that, more like 20 minutes, and in that, about 16 minutes of run time)

I have yet to hook up a meter to the TPS, which I read is a weak point in these cars.

I would like to know if a user with a runner could start and run (durring cold start) their car, or if the TPS is needed beyond being plugged in for the cold start phase (to actually start the car)?

I know in some domestics the car will still start and run.. a little slower to start, and lacking power, but it would run enough to idle at a minimum...

I ask this because I am aware it is not truly a computer, but more of an analogish feedback system.

I have read that the car should be able to start and crippled drive with the air flow meter unplugged, it should just drive very poorly..

So, to recap, Fuel pressure and flow are good, engine will run at least 50 seconds normally from a cold start (even on a warmish day (75F)) then suddenly dies.

And then restarting immediately for a short period is possible as described, indefinitely.

___

My satellite internet provider capped the connection early this morning, so picture posting will take some time with other online interests earmarking some of the available bandwidth remaining...
___

Thanks for all of the good ideas everyone... Haynes manual is not available locally... maybe online or out of town..

That is why I asked here... I expected a few of y'all fairly memorized the rebuild manual for your favorite car.

___

RE: Rarer car.... yeah, it is numbered 716 on it's plaque in front of the 5speed shifter... and it is indeed red/black with a gold pinstripe and burgandy interior or whatever color people are calling it these days...

Decals on the outside are all gone with no remaining evidence of their presence... unfortunately.... that and the mags have been replaced with chrome ones...

The original wheels are long gone.. we may want a set if anyone knows where they are to be had... black accent most likely would be our choice.
___

Thus ends this post,
Aaron

CWHammer

It sounds like you have a fuel delivery problem after the cold start circuit closes. It's been a while since I researched that one but I do remember that the cold start valve(7th injector) will stop dumping fuel after warm up but I don't remember the details. Check out xenon's page to get the FSM and forget the Haynes manual. All of the details are in the FSM.

WildmaN

Pertaining to the wheels. I have a nice set of the iron cross wheels with black accents. And the center caps also. Hit me up...and we can maybe discuss a price. And I'll try to get some pics for you. atranfanatic@yahoo.com

No-Z-Idle

Hey Everyone!

Pictures are up, I just had to wait for the satellite's cap to be removed..

You can see them at http://www.hqdeals.net/gallery/index.php?cat=12

There's a REALLY ugly one shooting up at the unibody version of a frame, I believe... or that is what it was before it was badly damaged at some point after my friend sold it, and before buying it back..

No need to fear the picture sizes, my gallery software is gentle till you click a picture a second time... then they jump to 6MP camera native JPG files.. which if you click again, close...

Some of the smallest thumbnails in the album are great viewed only as thumbnails, and more interesting shots may look better in the intermediate view or the full sized... whatever the case, it's handled.

I am waiting for a better day to go out and take a deeper look.. looking under the car was definitely discouraging...

I will add a picture of the #716 plaque next time I get out to the car.. (The ashtray obscured it while I was taking pictures, so I missed it... )

More later,
Aaron

KasbeKZ

first step: remove coffe mug.

second step: remove mouse nest

third step: ........... subjective?

Bleach

Nice! I'm glad you showed the gauges.
I just looked at a 10th red/black last night and turned it down. Wow, your car there makes the car I rejected look really good!
This car I saw had a 1979 130mph speedo but with 6 digit odometer and as far as I could tell it appeared factory. It was weird. Many things looked weird with that car. It had been repainted once and needed work on all sides but was not rusted out like the car your friend has.

Niku-Sama

wow, whatta ****in mess. but atleast the rust that i can see is easily gotten too, the insides look pretty well nested in, if i were to do any thing i would stip the inside and take a pressure washer to it.

KasbeKZ

yeah get it good and wet.

Albert

Start with a new set of plugs & air cleaner. Check out the air inlets for
obstructions. Buy a Fuel pressure gauge from J.C. whitney for $20.
Fuel feed pressure to fuel filter (replace filter too $5) should be 30-35 psi
for a healthy fuel pump.

If you haven't changed fuel...throw in some DRYGAS, get it at any auto parts
store or an equivalent. It's a Fuel "Drying" or de-mosituresizer 3$.

I have a 28 year old 280ZX Anniversary Black/Red myself and it runs like a
Swiss watch as long as I don't start adjusting things that don't need adjusting. That year is an excellently engineered vehicle and will run quite
aways out of spec if you've got a good 40,000 volt spark, fuel and air. The injectors will probaly need a purging and the Drygas will do that.

Taske a look at the old plugs and see if they are fouled or oily. If the previous owner ran it right the plugs should be light to dark beown with NOT
a lot of crud grown on them. I just regapped mine to .040 to see how it would run,,,and it was fine for a couple of months at which point I bought
a new set of NGK standards. Look for vacuum hose leaks, loose belts, etc.

Good Luck,

Albert

The big tip for a new owner is that you don't need to buy million dollar parts
for it to make it run. Aftermarket everything is the only sane way to go....
unless you're independently wealthy.