WALTSTAR

SO HERE WE GO...
Had the 84 usa with standard since 97 in a garage and could start it with no problem after not touching it for a year.
It has been under a carport covered on blocks since 2009 and when I went to start it last fall, crank forever with no result.
What Ive done as listed below now gets her to stumble and shut down after about 3-5 seconds.

drained all old gas,
new fuel pump and filter,
removed and cleaned all grounds,
removed and cleaned fusebox and contacts,
new ignition box,
new thermo-time switch,
new coil,
new cold start valve,
flushed all injectors,
all new rubber hoses under hood,
new distributor cap and rotor,
new spark plugs,
new green wire.


rebuilt the brake calipers, rotors, sensors, master and clutch cylinders, ball joints, changed trans fluid to amsoil.

Does anyone have any ideas? injector signals maybe?

Ninjaxz750

I see nothing regarding checking/ replacing relays...cleaning yes, checking or replacing no.

Just a thought from a not very good wrencher.

blue928

Had the same problem with mine after sitting, replaced the fuel pumps went through the electrical, went on rennlist, found and down loaded the service manual very large could be a million things right. Finally gave up had it towed to the dealer (try to avoid, lol) the belt dried out and the teeth stripped out but the belt was still in place. The engine would turn over but would not see oil pressure so it wouldn't start. $1500 later.

James Bailey

the 928 will start without oil pressure.....just will not run all that long and lifters will make a lot of noise...until the bearings seize
With teeth missing the camshafts are miss timed spark is mistimed....not going to start..
Since this car IS RUNNING it sounds like it is starting off the cold start injector sputters until that shot of fuel is gone. I recommend you get an injector noid light and see if you are getting a signal to the injectors...
We know it has spark we know it has compression know the cold start injector is working..... time to confirm that the other 8 injectors are getting a pulse.

WALTSTAR

The injectors get their signal from the box in the passenger footwell, correct?

The Deputy

How long will it run on ether?...if sprayed/misted into the air box. Can you keep it running longer than normal? If so, if be diving into the fuel delivery system...or the fuses and relays that control there operation...or sell it...to the first person that recommends using ether...for a hundred bucks.

Brian.

Mrmerlin

since it sputters it will run with fuel, ether not needed.

follow JBs advice report what you find

WALTSTAR

I wouldnt think of using ether as I have limited its use to carbs. I wouldnt want to compromise whats behind the "barn door' as I dont want to have to change out that unit if I can avoid it. What are the chances that the electronics in that air meter are bad? Which relays power the brain that sits next to the fuse panel and controls the injectors?

James Bailey

please get the noid light...
.go to 928 International site find the tips tech section and look up the fuse and relay chart for your year ...print it out it will tell you what each fuse and relay does. Something you need to CARRY in the car always !

WALTSTAR

I have the factory manual. I will check it in the AM.

The Deputy

This...
To this...

Could you describe "stumble" a little better? Is it actually running or just trying to run?

You've replaced a lot of items...especially ignition parts...but what are the results and why did you go this direction? Do you have a strong spark, now?

After looking at your concentration on ignition issues, that's kind of why I recommended ether...if you can get it to run for seven or eight seconds, cleanly, while moving the throttle control a couple times...that rules out a lot of stuff....like spark and timing. But if you don't feel comfortable using it...don't. I still think you need to concentrate on your fuel delivery system at the injector.

Good luck,

Brian.

WALTSTAR

I have a really fat spark. Im thinking that my injectors are not firing. it runs really rough for 3 seconds or so. It has to be running on the cold start shot. Relay #8 and contacts for the brain will be checked tomorrow.

James Bailey

and for less than $10. you can stop GUESSING and KNOW ...this is mental masturbation .... self abuse !! Had you tested the injectors FIRST you would have not needed to do most of the stuff you did on the ignition system...
If you remove the injection brain relay from the panel if you are comfortable and clear about which pin does what you can jumper it other wise carefully bend back the tabs and remove the metal cover. You can then carefully wedge the points closed with a match stick but use extreme care NOT to break the ultra fine wire or it will never be relay again. I have done this on the side of the road when my 1980 opted to shut down....Went to work and bought a new relay took all of 5 minutes part of which was finding a small twig at the side of the freeway.
Your car has two resistors in the ignition system normally the coil never sees 12 volts but when cranking on the starter motor it passes only through one resistor when in the run position it MUST flow through BOTH...which means the car will start and run when cranking but dies when the key switch goes to the run position if you have a bad resistor......all of which is why I suggested a noid light. Add in the fact that the fuel pump relay needs an ignition signal to keep the pump running in the ignition run position and it all gets way too interesting.
Here too there are simple things to help figure out what is wrong....you can run a jumper wire from the jump start post to the small + terminal on the coil. You can also run a jumper wire from the battery down to the fuel pump under the fuel tank. just do not leave them on for very long......
One potential problem of fixing things which are not broken is sometimes new parts do not work , or in the process you break or disconnect something else making more than one reason for the care to no longer run.
Which is why I always recommend a careful logical approach to getting a car to run. AFTER it runs you can then start replacing other things if you feel it needs it but you are working on a car which runs so if you changer plugs and then it misfires you KNOW IT and need only look at the plugs.....

WALTSTAR

The reason I changed so many components is because they clearly needed to be replaced (vis a vis the thermo time sensor being out of spec, the cold start valve having corrosion around its orifice, and the injectors being clogged from sitting with "kerosene" around them for so long)...
I didnt have the luxury of being able to work on the car regularly as for the past few years have been dealing with a spouse's serious medical issue (brain surgery) that she still hasnt fully recovered from.
I dont mind tinkering inspecting/examining/tinkering with the car as it gets me as familiar with it as I am with chevelles (got a problem or need one of those built, Im the man for you).
In the course of my working on the car, the resistors are found to be within spec (as per the manual that I purchased shortly after buying the car).

further questions...
1) Does the crank position sensor tell the plugs when to fire, the injectors when to fire, or both?
2) if I touch the relays numbered 8 and 19 should I feel them click when I turn the key to start or run?


I appreciate all the help you guys offer and havent decided to ignore any of the advice (noid light), I just dont have the time to play with it indiscriminately and am looking for the most likely direction. Im leaning towards the 8 injectors not firing because of a relay or brain issue.
Thanks!

James Bailey

....the green wire off the distributor drives the tachometer and tells the fuel injection brain that the engine is running as well as feeding the spark box up front by the jump start post.The injectors batch fire on all cylinders open valve closed valves it does not care. The injection brain controls pulse width depending on the needs of the engine based on the information provided by various sensors.
The distributor is fitted with a Hall signal generator which sends the pulses...