What makes these trucks destroy distributor caps/rotors?

[454cid]

I wonder if the old coil in cap CCC distributors of the early 80's could be used in our trucks? Anybody ever tried it? They were just as tough as the mechanical advance HEI's but with ECM timing control.

Are those the distributors that were paired with the electronic Q-jets?

 

[Scooterwrench]

Are those the distributors that were paired with the electronic Q-jets?

Yes!

 

[AuroraGirl]

I have one truck in particular (1999 C1500 Sub) that will ruin a distributor in about 6 months. Also, it seems to really have a craving to do it at the most ridiculous times.

My first cap was a brass Autozone Durasomething. All the others have been AC Delcos, with aluminum. I'm taking a wild guess here that Delco sucks in this case since the brass held up longer.

I've read that we should probably be drilling some tiny holes in the cover to provide ventilation. I DEFINITELY live a stupid-humid, hot environment (coastal SC).



If you want to read my sob-story, here it is. Truck just loves to act up on ironic/bad days.

1) My second son was born. Started misfiring THAT DAY as I drove back to the house to check on my in-laws and older kids. Misfire, #3 or 5, can't remember. New distributor cap solved it.

2) 9 months later, pulling out of driveway for a 300 mile trip with the family....started misfiring. Cyl 5. New distributor cap solved it.

3) 4 months later, driving to the parts store to buy some hand tools to begin my front end rebuild.....started misfiring, Cyl 5. Taking a wild ass guess about what it is.



My OTHER 99 Suburban (K1500), same engine, is about a year on the Delco (aluminum) and it runs like a champ.

with a suspected bad distributor cap, take a single spark plug wire and put one end of a DVOM in the end by the plug

Then, with it on OHMS setting, use the other lead on each of the other spark plug wire ends by the plug.

Do you get anything but "OL" or infinite resistance? Cap has failed if you got anything other than OL/infinite.

 

[AuroraGirl]

Are those the distributors that were paired with the electronic Q-jets?

Computer Command Control yes indeed, a lot of them had ESC as well built into their setups. very crude but kinda impressive. Very small amount of corrective ability compared to even TBI

 

[Scooterwrench]

Computer Command Control yes indeed, a lot of them had ESC as well built into their setups. very crude but kinda impressive. Very small amount of corrective ability compared to even TBI

If paired to a T400 ECM wouldn't it run the same timing events as the small cap dist.? I must have tossed a dozen of those thing in the $hit can and replaced them with mechanical HEI's and Q-jets. Kind'a wish I had one now to experiment with.

 

[AuroraGirl]

If paired to a T400 ECM wouldn't it run the same timing events as the small cap dist.? I must have tossed a dozen of those thing in the $hit can and replaced them with mechanical HEI's and Q-jets. Kind'a wish I had one now to experiment with.

not sure to be honest, I dont know much about the CCC or early TBI esc. I know a bit more about the pre-CCC but still ESC large cap distributors with extra wires but went to a standalone module, they were pretty crude functioning.

 

[Road Trip]

You don't have the same distributor cap design. GM started using the Vortec name on the V6 and that was prior to the changes that most associate with the term "Vortec". Those changes came with the V8s switch to multiport fuel injection, and the changes to the heads. What you have is a TBI V6 much like the TBI V8s, prior to Vortec being applied to them. The caps are a standard cap design, where as the later caps are a "crab" (they kinda look like a crab) that have the connections crossing over, or running very close inside the molded plastic.

edit: apparently the plural of crab is sensored

Irregardless I'm sharing my experiences with a v6 new distributor failure to which someone asked from someone with personal experience.

Greetings Dillhart541,

Welcome to the GMT400 forum. Sounds like you are having quite a time with your '89.

As for this thread, it started out originally as a question about the relatively short usable
lifespan for the V8 'crab caps', which were introduced to the GMT400s as part of a
redesign/upgrade for the '96+ model years.

Then in reply #24 a member asked if the crab cap V6 had the same short lifespan issues.
So this is why @454cid stated what he did above. And he is right, for the correct dizzy cap
for your '89 4.3L is the old school 'firing order' style. (See 1st attachment)
The crab-style Left & Right bank V6 cap is in the 2nd attachment.

The rest of the Vortec naming confusion was that GM used this as a marketing tool to refer
to a new swirl-inducing ski ramp inside the intake port starting way back in '85. But this
new design intake port fed into a conventional (let's say V8 TBI like) combustion chamber.
('88-'95 GMT400 4.3 V6s - see 3rd attachment)

In the '96+ 4.3L V6 & 305/350 V8 engines the new heart-shaped combustion chambers
were introduced. (See 4th attachment.) And for what it's worth, '96 was when the 'Vortec'
name was added to the V8s. And now in 2024 a 'true' Vortec engine is considered to be the
V6 & V8 engines with these newer, better breathing heads.

GMT400 perspective:

* '88-'95 4.3 V6: 160-165hp
* '96+ 4.3 V6: 200hp

Note: A pretty decent Wiki article on the evolution of the 4.3L V6: 3/4 of the SBC

****

Having said all that, I am still interested in hearing how goes the battle with your '89 4.3L GMT400.
When you get that engine bay weatherproofed enough to handle your off roading adventures please
report back with what it took to make it right again.

And all this makes me wonder if there's anyone out there who has owned both Pre-'96 and 96+
GMT400s with the 4.3, and if they remember if those caps lasted the same length of time with
the same driver? Or do you remember a big difference in longevity between the two?

Anyway, I hope this clears up how the early GM marketeering use of Vortec to describe a new
intake swirl port has changed to whether or not the engine has the fast-burn heart-shaped
combustion chambers.

FWIW --

 

[AuroraGirl]

Greetings Dillhart541,

Welcome to the GMT400 forum. Sounds like you are having quite a time with your '89.

As for this thread, it started out originally as a question about the relatively short usable
lifespan for the V8 'crab caps', which were introduced to the GMT400s as part of a
redesign/upgrade for the '96+ model years.

Then in reply #24 a member asked if the crab cap V6 had the same short lifespan issues.
So this is why @454cid stated what he did above. And he is right, for the correct dizzy
cap for your '89 4.3L is the old school 'firing order' style. (See 1st attachment) The
crab-style Left & Right bank V6 cap is in the 2nd attachment.

The rest of the Vortec naming confusion was that GM used this as a marketing tool to refer
to a new swirl-inducing ski ramp inside the intake port starting way back in '85. But this
new design intake port fed into a conventional (let's say V8 TBI like) combustion chamber.
('88-'95 GMT400 4.3 V6s - see 3rd attachment)

In the '96+ 4.3 V6 engines the new heart-shaped combustion chambers were introduced
on both the V6 & V8 engines. (See 4th attachment.) And for what it's worth, '96 was
when the 'Vortec' name was added to the V8s. And now in 2024 a 'true' Vortec engine is
considered to be the V6 & V8 engines with these newer, better breathing heads.

GMT400 perspective:

* '88-'95 4.3 V6: 160-165hp
* '96+ 4.3 V6: 200hp

Note: A pretty decent Wiki article on the evolution of the 4.3L V6: 3/4 of the SBC
****

Having said all that, I am still interested in hearing how goes the battle with your '89 4.3L GMT400.
When you get that engine bay weatherproofed enough to handle your off roading adventures please
report back with what it took to make it right again.

And all this makes me wonder if there's anyone out there who has owned both Pre-'96 and 96+
GMT400s with the 4.3, and if they remember if those caps lasted the same length of time with
the same driver? Or do you remember a big difference in longevity between the two?

Anyway, I hope this clears up how the early GM marketeering use of Vortec to describe a new
intake swirl port have changed to whether or not the engine has the fast-burn heart-shaped
combustion chambers.

FWIW --

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[454cid]

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I did not know that the V6 and I6 overlapped in production. I had always thought the 4.3L V6 replaced the inline completely.

 

[Scooterwrench]

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I never knew they didn't offer the 350 in '85 and that the 292 was still being produced.