Possibly not running on all 6 cylinders. Will a temperature reading work? (Page 4/6)
Cliff Pennock MAR 23, 07:42 AM

quote
Originally posted by buddycraigg:

one of the fuel injector fuses was blown.



I had already checked the fuses.


quote

The spark tester thingies really only give you 1/3 of the story. and are almost useless.



Yes, but it's 1/3 of the story I would like to rule out if it turns out one of the cylinders is out.


quote

I would GIVE you the ones I have, but would cost more in shipping than what they are worth.



I already bought one. In fact, I bought the one from the picture.

If I had a garage, I would have taken the thing apart long time ago and fixed every damn issue the car has. But I don't and I need to work outside on a public street. Also, this is The Netherlands. Meaning this time of year, it rains, it's cold and it storms. As in every freakin' day. I've been able to do one hour of troubleshooting this year so far since that was the only time it was actually not raining and/or "warm" enough to not freeze my nuts off.
theogre MAR 23, 08:04 AM

quote
Originally posted by Cliff Pennock:
Will one of these work? (and test it at the distributor cap, not the spark plug)

CLICK FOR FULL SIZE

No. & often not even if you but the end direct to ground as often the bulb would fail because make to have a plug in series.

Is made to see if HV side sends power to a plug in the first place like trying to see if coil(s) etc works and still runs the plug in series. This maybe you problem & need new spark plugs, plug wires or cap/rotor set but often will "blow" the bulb etc if you try direct ground test try to find a "dead" cyl.

Example I shown should be available at amazon etc under many brands. Or maybe either of these that made for grounding to test.
https://www.amazon.nl/Vonke...ircuit/dp/B0CV5FVM3F
https://www.amazon.nl/Sweet...tester/dp/B09T2BP3CL
both set for maybe ~ 1/4 to 1/3 inch, (10mm Max) because easy jump in standard air pressure.

If have old spark plug... cut/break the ground electrode & clamp the metal body to the engine. Not as good as above Examples but should help short term.


quote
Originally posted by buddycraigg:
I have a plastic spark plug wire puller.
I do it all the time while it is running.
If you pull a wire and the engine does not change RPM, you found the bad one.

Do whatever you want but Every time you to this to HEI and others... High Volt side will find another path to ground farther upstream & often damage HEI or DIS coils & more but damage may not be seen right then.
HV/Secondary Can: (Not limited to these...)
Jump secondary to primary in the coil.
Burn the ICM because of above.
Start at minimum Carbon Tracking in/on Dist Cap or Rotor.

[This message has been edited by theogre (edited 03-23-2024).]

Patrick MAR 23, 04:32 PM

quote
Originally posted by Cliff Pennock:

...you are under the (false) impression I only want to know if a cylinder sparks or not.



No, I was correcting/clarifying your following comment.


quote
Originally posted by Cliff Pennock:

If the RPM goes down, that plug has spark. If the RPM doesn't go down, that plug doesn't spark.



If the cylinder has spark (and a good spark plug), but no compression and/or no fuel, that would also cause the RPM not to go down if you ground the spark.

Anyway, I realize you're getting somewhat conflicting advice from all sides. I'll just say that the procedure I outlined is a helluva lot easier than pulling individual spark plug wires from all six plugs.
Cliff Pennock MAR 23, 06:03 PM

quote
Originally posted by Patrick:

If the cylinder has spark (and a good spark plug), but no compression and/or no fuel, that would also cause the RPM not to go down if you ground the spark.


Exactly. So removing (or grounding) the spark plug wire from a properly working cylinder, (one that has spark, compression and fuel) will always cause the RPM to drop. But if a cylinder has no spark, no compression or no fuel, pulling the wire would make no difference (or hardly any difference). So it's still a valid test.
Patrick MAR 23, 06:06 PM

Yes, you've got it!
Stingray92 MAR 23, 06:07 PM
Momentarily, till the iac adjust.
Cliff Pennock MAR 23, 06:07 PM
Cool. But what is it then that I misunderstand? Because I never thought otherwise.
Raydar MAR 23, 06:10 PM

quote
Originally posted by Cliff Pennock:

Exactly. So removing (or grounding) the spark plug wire from a properly working cylinder, (one that has spark, compression and fuel) will always cause the RPM to drop. But if a cylinder has no spark, no compression or no fuel, pulling the wire would make no difference (or hardly any difference). So it's still a valid test.



I would add an additional step. The ECM is going to try to maintain a certain RPM. "Killing" a cylinder may not make a noticeable difference - at least in RPM - because the IAC will try to correct for it.
Before killing cylinders, I would be inclined to unplug the IAC.

Someone please correct me if I'm wrong.
Patrick MAR 23, 06:11 PM

quote
Originally posted by Stingray92:

Momentarily, till the iac adjust.



I suppose the IAC could simply be unplugged... but there's no need to be grounding the spark on each cylinder for any extended period of time.

[EDIT] Raydar beat me by a minute.

[This message has been edited by Patrick (edited 03-23-2024).]

Patrick MAR 23, 06:15 PM

quote
Originally posted by Cliff Pennock:

Cool. But what is it then that I misunderstand? Because I never thought otherwise.



Perhaps it's a language issue, because what you "thought" and what you posted didn't entirely agree with each other. Anyway, you're now on the right track.