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Discussion Starter #1 (Edited)
Hey all!

Nixie here has been having some running issues for a while, and now I'm desperate enough to hop on a forum after she stopped starting entirely.

In the last week, she occasionally would need to crank for extended periods of time before starting, but after kicking over, she'd drive with no significant issues. After a 4 hour drive home from Iowa, she was parked for a day. When I came back out, she started, but died after applying the accelerator.

After this occurred, she refused to start at all. It seemed like a fuel issue, so I jumped B+ and Fp in the diagnostics port, which (audibly) spun up the pump, though I haven't yet pressure-tested the fuel line. That comes tomorrow, however.

Additionally, I checked the injector pulses with noid lights.

I did the old screwdriver test with the spark plug wires, and she is getting spark (at least to the plugs).

I then tried to fire her up with ether, and she didn't even stumble, let alone start.

I then tested for CEL codes using the blink method, but the ECU claims there are no faults.

My best guesses:
-Timing belt skipped (isn't supported by previous intermittent failures to start)
-Low fuel pressure (doesn't make sense with failed ether test)

Thanks for any thoughts and suggestions!

-Zack
 

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...Timing belt skipped (isn't supported by previous intermittent failures to start)
Not everything has to be connected. Your current problem could be unrelated to the previous one.

The belt could also have skipped twice. That is not improbable if the tensioning is wrong to begin with.
 

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Have you replaced your capacitors? Mine had issues starting, keeping a stable idle, and would die if I didn't keep the idle up myself. The ECU will not show a fault for this.
 

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Discussion Starter #4
Meller and Nabera, thanks!

Idk why I didn't consider that the timing had skipped twice---I'll take a look later today. I'd also heard about bad capacitors in the tachometer, but I'd not read about the ECU issues up until now---that definitely sounds like a potential winner. :D

I'll update once I've done some more diagnostics. <3
 

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Just keep in mind that the capacitors do not need to look bad to be bad. The C810 I pulled out looked brand new and shiny, but was definitely dead.
 

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Discussion Starter #7
Copy that---I'm ordering caps to replace all of the electrolytics. I pulled the ECU, and I can't see any obvious component failures, but it doesn't cost much time to replace stuff.

I'm also building a couple DIY current-clamps to directly test the ignition and injection timing (relative to the crank position). I'll post some photos if I can get it working tomorrow. :D
 

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Discussion Starter #8 (Edited)
I bought an oscilloscope from the 80s and fashioned up these AC current clamps from ferrite toroids I found in a PC power supply. Now, I'll see if I can get some meaningful timing information...

UPDATE:
The final picture shows one still from the first test--the top line is battery voltage (bouncy due to the alternator pulses) and the bottom line is spark plug current on cylinder 4 (using my homemade current clamp :p ). The little blip on the bottom line is when that cylinder fires.

Something unexpected happened: the car started, though she seemed to be running rough. I'll retest with the EFI fuse out to avoid starting the engine---otherwise the timing won't be measurable. I'll show you what I mean once the garage airs out...
 

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Discussion Starter #9
This testing method isn't my invention---this fella did it before me with better equipment:

The idea is that the compression of air in the cylinder during cranking will put the heaviest load on the battery when the starter is approaching (and very close to) TDC. I'll be comparing the spark timing to the minimum battery voltage, which I think is an appropriate approximation, though it may exaggerate the timing delay a bit.

The results:
top trace: battery voltage
bottom trace: spark current
~8ms delayed spark
~425ms / 4 cycles (425ms/720 deg) <== this was found in the audio
==> 8ms * 720deg / 425ms = 13.5deg retarded timing
(the below delay was verified on several cycles to make sure it was consistent)
68929

audio output (where the cycle rate was found)
68930


In short, I think that it's reasonably good proof that the timing belt skipped. I checked the tension with a finger and found the belt looser than I expected. I'll post the video in a bit. :)
 

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Discussion Starter #10 (Edited)
Here's the test vid (though I admit it's difficult to understand what's going on without context :p).

After all that, I figured I better get her to a mechanic. Since the 5SFE is non-interference, I figured I'd attempt to drive her if it would start---and she did. She ran like ass, had no power, and vibrated at idle. I feel pretty confident that the diagnosis was correct. :D

Now to let the mechanic do the work---I'm not in my hometown, so I don't have the tools to do it myself. Also, school is starting back up on Tuesday... Anyway, I'll update once the mechanic has taken a look!

Thanks so much for the help!
 

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The usual way to check for jumped timing is to take off the timing cover and look at the marks on the gears. Never heard of this method before.
 

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The usual way to check for jumped timing is to take off the timing cover and look at the marks on the gears. Never heard of this method before.
You know, I was going to suggest this too, I'm glad you got to it first [because I feel embarassed at being so old-fashioned and retro, in this day and age. At least now I know there is two of us stone age relics here]. Ha ha. Ha ha ha ha.
 

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Discussion Starter #13
If I had so much as a proper toolset I'd have done it that way... >.<

I didn't really have the space or tools to get the lower timing cover off to check the crank pulley marks. I've done that on a few other cars, but the timing belt is jammed all the way to the side in this car... maybe I'm making it harder than it has to be, but it was fun, regardless :p
 

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I have never heard anyone say before that he had to use an oscilloscope because it was the only tool that he had. :ROFLMAO:
 

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Discussion Starter #16
Guess who's baaaaack!! >.<

Nothing's fixed! (and my oscilloscope method appears to not be very accurate :p )

New information:
  • After the above tests, I got Nixie to start. She ran like garbage---this was found at the shop to only be one injector connector with the latching tab broken off---this is verified not to be the cause of the no-start situation. All they found was the disconnected injector. They reconnected the connector and she seemed to run normally.
  • The mechanics also verified good fuel pressure, spark, and timing.
  • After I got it back from them, I found that the car hesitated at high throttle inputs. She'd cut out if I tried to accelerate hard from idle.
  • I drove 120 miles from KC to Manhattan with no other issues.
  • I take her to a car wash and leave her idling---after I'm done, I try to drive away and as soon as I hit the accelerator the car dies. Since then she hasn't restarted.
  • Since then I've replaced the fuel filter (just tonight). Still no start. She cranks fast and clean, but there's not even any stumbling or ignition presence at all.
There's one connection between events that I hadn't made until today: water makes things worse. The other time I've had an unexplainable no-start was when the car died when I was driving on the freeway through heavy rain/standing water. She restarted/died/restarted a couple more times before I made it home. This most recent event saw the engine die after leaving the car wash. Note: the event that sparked this thread was not water-related [just thought some extra info may be useful].

Thanks for your help so far! Let's hope we can run down the issue.
 

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Did you ever get a chance to replace your capacitors? I was stuck troubleshooting everything I could think of for several months until I investigate my caps.
 

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Discussion Starter #19
Replace the high voltage ignition components. Plugs, wires, cap, and rotor. If worst comes to worst, the coil also. Even microscopic cracks can cause high voltage insulation to fail.
That was actually something I ran down months ago--I didn't think to include it. All those components are new.

Did you ever get a chance to replace your capacitors? I was stuck troubleshooting everything I could think of for several months until I investigate my caps.
Thanks for the reminder! I'll have to do that. I ordered the wrong parts, so I've got to do that again...

"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." – Sir Arthur Conan Doyle, stated by Sherlock Holmes.

I'll update once I've changed the caps.
 
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