$0D Re-enabled knock sensor, getting code 43 knock sensor circuit failure

So with my new 383 engine I just built, for my turbo Blazer, I decided to install the knock sensor. I have not had it on the truck for years, but I would really like to use it now. I was lucky enough to find a V8 memcal ( I was using a V6 ) in the salvage yard out of a 94 full size truck, but it was a 305, not sure if that makes a difference or not. Anyway, I bought a new knock sensor from Autozone which I had matched out to what was originally in my truck, 1994 Full Size Blazer with a 350. Every thing is hooked up correctly, I ohmed the wire back to the PCM and its good. As soon as I start the truck I get this code. I know there are a lot of different combos GM had with the knock sensors. Could it be that my combo just will not work?

Electrically you should not have a problem with that sensor and memcal. I'd follow standard diagnostics.

I just did a quick search on Rockauto, and it looks like the 305 truck in 94 used and AC Delco 21391 knock sensor, and the 350 Blazer in 94 used knock sensor part number 21392.

21392 will be the correct KS for the 16197427 platform and Memcal for a 350 or 454, it should ohm out to 3.9K ohms or there about.

DKS208 is the NAPA part # I use.

305 trucks used a different KS , so the Memcal you pulled would have a different filter board.

TOM

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Originally Posted by Nasty-Z

21392 will be the correct KS for the 16197427 platform and Memcal for a 350 or 454, it should ohm out to 3.9K ohms or there about.

DKS208 is the NAPA part # I use.

305 trucks used a different KS , so the Memcal you pulled would have a different filter board.

TOM

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Ok, well I have several PCM's 16197427 and 16196395's. The 305 had a 16196395 in it, I grabbed the PCM as well. So I can match the Memcal to the PCM, but it looks like I still have the wrong knock sensor. I think right now I have the stock 7427 computer in my truck with the 305 memcal and a 350 KS.

What would using the 305 KS do, just be more sensitive?

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Originally Posted by 96lt4c4

Ok, well I have several PCM's 16197427 and 16196395's. The 305 had a 16196395 in it, I grabbed the PCM as well. So I can match the Memcal to the PCM, but it looks like I still have the wrong knock sensor. I think right now I have the stock 7427 computer in my truck with the 305 memcal and a 350 KS.

What would using the 305 KS do, just be more sensitive?

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You could use a KS for the 305 that would match the Memcal , that would work fine . My guess is like yours , I think it would be a tad more sensitive due to the smaller bore of the 305 .

Let us know the results. 305 Memcals seem to be a bit more plentiful that their 350 / 454 counterparts.

TOM

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Originally Posted by Nasty-Z

You could use a KS for the 305 that would match the Memcal , that would work fine . My guess is like yours , I think it would be a tad more sensitive due to the smaller bore of the 305 .

Let us know the results. 305 Memcals seem to be a bit more plentiful that their 350 / 454 counterparts.

TOM

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OK, I may recheck the yard here in the next couple days to see If a 350 truck show's up. They have a pretty quick turn around. I didn't realize the 305 memcals were so plentiful. I knew the V6 ones were.

I've been looking for 454 memcals for the '7427 / '6395 for a while now , they show up from time to time and I try to scarf them up ......

The pick-a-parts around here have lots of 305 trucks with '7427's and 6395's in them , never thought of trying those memcals in a conversion.

TOM

Well, I installed the 305 KS, light came on. I am using the computer, and memcal from the same truck. Brand new KS.

I don't know may the memcal KS circuit is bad.

Quote:

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Originally Posted by Nasty-Z

I've been looking for 454 memcals for the '7427 / '6395 for a while now , they show up from time to time and I try to scarf them up ......

The pick-a-parts around here have lots of 305 trucks with '7427's and 6395's in them , never thought of trying those memcals in a conversion.

TOM

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Quite the opposite from here, most of the trucks I run across in the yard have a 350 or 454 and the occasional 6.5. 305s are rare as hens teeth unless you find a G10 van and it seems most of them had 4.3s. It took me 3 different yards the last time I was searching for a 4.3 TBI memcal for a 395/7427. Finally found one in an Astro van sleeping peacefully after a massive rear-end collision.