Delphi TBI distributor discontinued(?). What's next best option?

[whiteboyslo]

I've been trying to source a Delphi CZ20001 for my 93 Suburban 2500 (454) for a couple of weeks now. Every place I try cancels the order. I finally called Delphi and they said it's no longer available and don't have a replacement option.

All the aftermarket options out there have horrible reviews, and I don't see an ACDelco (new) option. So, what's our best bet now? Anything else out there worthwhile, or should we start rebuilding junkers with ACDelco parts?

I'm currently working through a hesitation issue at part throttle that came about after I replaced an OReillys unit that died after 9 months. Even with an ACDelco ICM on it, it still hesitates.

Mike

 

[evilunclegrimace]

I have been running Untied Motor Products ignition parts in my trucks for a few years now and have had no problems.

Rock auto shows one in stock PN 9366 $117.00

 

[Schurkey]

should we start rebuilding junkers with ACDelco parts?

That's my plan. Screw the Communists.

I'm currently working through a hesitation issue at part throttle that came about after I replaced an OReillys unit that died after 9 months. Even with an ACDelco ICM on it, it still hesitates.

Connect a scan tool, look at the data stream. Good chance the distributor ISN'T the problem.

I'd want to know about the knock sensor activity, EGR, short- and long-term fuel trims, and the O2 sensor readings including cross-counts. (of course, ANYTHING in the data stream that looks out-of-place is a good clue.)

Thousands of years ago, I had some highway-speed misfire that eventually got worse and worse, turned out to be the pickup coil in the distributor. GM dealership installed a new main-shaft in the distributor. I suppose mainshafts are also discontinued.

 

[evilunclegrimace]

That's my plan. Screw the Communists.


Connect a scan tool, look at the data stream. Good chance the distributor ISN'T the problem.

I'd want to know about the knock sensor activity, EGR, short- and long-term fuel trims, and the O2 sensor readings including cross-counts. (of course, ANYTHING in the data stream that looks out-of-place is a good clue.)

Thousands of years ago, I had some highway-speed misfire that eventually got worse and worse, turned out to be the pickup coil in the distributor. GM dealership installed a new main-shaft in the distributor. I suppose mainshafts are also discontinued.

Delco still sells the distributor main shaft separately. The7.4 shaft is PN 10467353 and the 5.7 is PN 10467653 The same shaft fits both distributors

 

[L31MaxExpress]

What is GM using for the Ramjet crate engine?

 

[whiteboyslo]

Connect a scan tool, look at the data stream. Good chance the distributor ISN'T the problem.

I'd want to know about the knock sensor activity, EGR, short- and long-term fuel trims, and the O2 sensor readings including cross-counts. (of course, ANYTHING in the data stream that looks out-of-place is a good clue.)
.

Well, I guess this is where I sheepishly admit that, while I have a nice 1320electronics scan tool and both ALDL Scan Tool and ALDLDroid loaded on my phone, I only understand a fraction of the info it tells me. I know knock count is basically none at stock timing, none at 8 degrees BTDC if running 91 octane, and maybe 2 knocks for every WOT when running 87 octane at 8 degrees BTDC. Past that and some other very simple values (RPM, coolant temp, etc), the rest of the values might as well be Greek. (I've been playing with timing trying to get a bit more pep out of her. She seems to really wake up at 8 degrees).

My gut still says it's distributor-related, only because the hesitation started the day after I got it back from the shop after they replaced the bad distributor (long story as to why I didn't DIY this, but suffice it to say that I wish I'd done it myself so as to not deal with the crap parts). Could be related to them not putting something back correctly, but it all looks good. O2 sensor and EGR are both less than 2 years old, all ACDelco stuff.

Still, if you have a couple of parameters I should be watching specifically with the scan tool, as well as maybe a quick lesson on what the "good" values should be, I'm all ears.

Thanks!

Mike

 

[L31MaxExpress]

If you cannot secure a new GM one. Davis Unified Ignition is the best I have run aftermarket.

 

[Schurkey]

What is GM using for the Ramjet crate engine?

EXCELLENT question.

https://www.summitracing.com/parts/nal-1104060

Although, I won't promise that it uses the same module as the TBI applications. In fact, I'm wondering if it uses the "Marine" module.

Module aside, I can't think of anything else that would be different.

 

[L31MaxExpress]

EXCELLENT question.

https://www.summitracing.com/parts/nal-1104060

Although, I won't promise that it uses the same module as the TBI applications. In fact, I'm wondering if it uses the "Marine" module.

Module aside, I can't think of anything else that would be different.

The marine modules have the advance curve built into them for carb engines. The Ramjet has a functional EST system with a spark map programmed into the ECU.

 

[Schurkey]

The marine modules have the advance curve built into them for carb engines. The Ramjet has a functional EST system with a spark map programmed into the ECU.

Then I have no idea why the Ramjet distributor wouldn't be compatible with TBI.

If there's some reason it wouldn't be satisfactory...I don't know it.