Poping sound at idle, help..

[SiriusC1024]

First thing that needs to happen is find out why the O2's show such a big spread between banks. Wideband is all over the place, probably from misfire. Which bank is that in?

Another thing is the VIN in the tune is for a 1997 Camaro. In the log the VIN shows 1997 Buick Park Avenue. I can't say for certain if this table is hidden or simply doesn't exist, but Gen 3 LS has an injector control where banks are assigned. It could be the case that this table, assuming it's there, is having an effect if it's assigned for one vehicle config but not the other. On the transverse cars there is only one front O2, and all injector control for all 6 would be assigned to it. Longitudinal, like your Camaro, has an O2 in each bank. Did anybody at any point write a tune from another vehicle? This could explain a lot of odd things going on here.

You know I bet what happened is someone took the ECU from a supercharged car, Park Avenue Ultra in this case, and wrote a Camaro V6 tune over the top. Can't do that. You need a compatible ECU. The Supercharger tab in the tune is pretty useless. All it does is dump boost after a certain amount of time to unload the engine. Regular N/A tune setup can accommodate your build.

[LuminousX]

First thing that needs to happen is find out why the O2's show such a big spread between banks. Wideband is all over the place, probably from misfire. Which bank is that in?

Another thing is the VIN in the tune is for a 1997 Camaro. In the log the VIN shows 1997 Buick Park Avenue. I can't say for certain if this table is hidden or simply doesn't exist, but Gen 3 LS has an injector control where banks are assigned. It could be the case that this table, assuming it's there, is having an effect if it's assigned for one vehicle config but not the other. On the transverse cars there is only one front O2, and all injector control for all 6 would be assigned to it. Longitudinal, like your Camaro, has an O2 in each bank. Did anybody at any point write a tune from another vehicle? This could explain a lot of odd things going on here.

first off, thanks a lot for trying to help me figure this thing out, it's been an on going for years now, and I could never find the problem.

when I went turbo I had the original PCM in it, but HPtuner doesn't support 96 and so had to go with a 97 pcm, which i got from a 97 Camaro.. ever since the car had been giving problems, a while back i kept getting crank code that turned out to be the pcm, i had a spare pcm from a 97 buick that i used to replace the 97 camaro pcm, i had to write the 97 tune file to the 97 buick pcm because the car wouldn't start wth the file that came from the buick.. so that's why it says buick park ave, but the file is from a 97 camaro... i know, it's a shit show.

[SiriusC1024]

Looks like you confirmed my edit above. Sorry I just hadn't hit refresh on the page.

Crank relearn is a thing with the 3800's. Might have to use something other than HPT for that since it's broken half the time. Try a 97 Camaro V6 auto ECU and lets see if we can make it run. Did you check pinouts? That or get a refurb off eBay where you give them a 1997 VIN for programming. There are hidden tables beyond what's defined in the tune files we see. They're cheap and I've had good luck with them. On a Grand Prix, I once diagnosed a progressively worse stalling condition which turned into a no-start that required an ECU replacement. Turns out that's a thing, too. Keep us posted, and you're welcome for the help

[LuminousX]

Looks like you confirmed my edit above. Sorry I just hadn't hit refresh on the page.

Crank relearn is a thing with the 3800's. Might have to use something other than HPT for that since it's broken half the time. Try a 97 Camaro V6 auto ECU and lets see if we can make it run. Did you check pinouts? That or get a refurb off eBay where you give them a 1997 VIN for programming. There are hidden tables beyond what's defined in the tune files we see. They're cheap and I've had good luck with them. On a Grand Prix, I once diagnosed a progressively worse stalling condition which turned into a no-start that required an ECU replacement. Turns out that's a thing, too. Keep us posted, and you're welcome for the help

I tried the crank relearned and like you said it doesn't work.. at this point I have 3 PCM (1) original with the car which is a 96, (1) 97 Camaro Auto, and (1) Buick Park Ave. At this point I'm thinking of putting the 96 PCM back in, but I've got bigger injectors now and threw out the old ones.. at least that way I would know if the PCM is the main issue because at this point I'm just throwing money at it.. 😩. I wish I could just pull the 96 file and write that to the 97 PCM.

[SiriusC1024]

Put the 97 ECU in. Should be pin-for-pin compatible with a 96. If you'd like read out the file and post it here. We'll work through getting it running and tuned up.

[LuminousX]

Put the 97 ECU in. Should be pin-for-pin compatible with a 96. If you'd like read out the file and post it here. We'll work through getting it running and tuned up.

well here's an update.. I decided to follow a friends advice and put the 96 Original PCM in the car even thou it has the 31lb Bosch injectors installed, I did this knowing I had front o2 sensors and the car would at least pull some fuel out.. well my wideband showed it was idling at 14.0-14.5... it pulled a bunch of timing, or maybe that's just how that spark table is setup.. take a look at these logs

24-07-02 21-46-32.hpl
24-07-02 21-37-46.hpl
24-07-02 21-25-42.hpl

and the best part is, it didn't pop once.. is it due to the fact that the PCM came from the car and it works the best, or is it that a bunch of timing was pulled??

[LuminousX]

decided to take a video

[SiriusC1024]

It almost looks like timing is inverted. Goes way negative when you give it gas. It can physically be doing that. B1S1 is still looking wrong, yet fuel trims aren't split between banks. Maybe it's compatibility of Scanner with that 96 ecu.

Figured it'd run fine on the 96. Still need to tune it, so try the 97.

[LuminousX]

It almost looks like timing is inverted. Goes way negative when you give it gas. It can physically be doing that. B1S1 is still looking wrong, yet fuel trims aren't split between banks. Maybe it's compatibility of Scanner with that 96 ecu.

Figured it'd run fine on the 96. Still need to tune it, so try the 97.

I tried a 97 Camaro PCM before and it didn't run right, but that PCM pretty much came out of a donor car.. no vin programmed or anything.. will getting one from eBay and having a 97 Camaro Manual VIN programmed into it work.. that seems like the best route.. but where do I get the VIN?? also that bank as an extender for the o2, maybe that is what's causing it to not read properly

[SiriusC1024]

Finding that VIN is going to be the hard part. I checked the HPT repository (tune available, VIN doesn't show up), eBay (manual listed, but it's actually auto), and AutoTrader. Not even a junkyard V6 5-speed ecu on eBay.

Didn't run right or won't run at all?

[LuminousX]

Finding that VIN is going to be the hard part. I checked the HPT repository (tune available, VIN doesn't show up), eBay (manual listed, but it's actually auto), and AutoTrader. Not even a junkyard V6 5-speed ecu on eBay.

Didn't run right or won't run at all?

it ran, but the timing won't stay where I put it, I command 15 and once it gets hot it goes to 25.. I have no control over it.. and then the popping starts. it's 100% the file.. something is turned off or not turned on and I can't see it because HPtuner doesn't give us a lot of tables..

P.S I keep seeing misfires on 2/5 when driving low speeds or high speed.. it's just a mess.

[SiriusC1024]

Oh I thought that was happening with the Buick ECU with Camaro tune written to it. Same thing happens with the actual 97 Camaro ECU?

[LuminousX]

Oh I thought that was happening with the Buick ECU with Camaro tune written to it. Same thing happens with the actual 97 Camaro ECU?

yep, happened with the 97 Camaro tune that came with the PCM, happened when I wrote that same tune to the 97 Buick PCM because the file from the buick wouldn't give me a check engine light or start.

[LuminousX]

Untouched_97_Camaro_Stock_Tune_11_10_2021.hpt

This is the stock tune from the 97 Camaro that I pulled 3 years ago, something within the tune isn't working right with the car... most likely tables that we can't see, but you can have a look, and I'll make any changes suggested.

[SiriusC1024]

Write this. Let's see what happens. It's in OL right now because of that B1S1 problem.

[LuminousX]

Write this. Let's see what happens. It's in OL right now because of that B1S1 problem.

OL.Spark.25.hpl
CL.Low.Spark.hpl

In OL on that tune I'm getting a lot of misfires on 2 mostly, I lowered the spark with the VCM scanner and it idled better.

[SiriusC1024]

What's CL.Low.Spark? Is that with spark lower or with CL re-enabled as well?

Which series wideband are you using through EGR?

[LuminousX]

What's CL.Low.Spark? Is that with spark lower or with CL re-enabled as well?

Which series wideband are you using through EGR?

I commanded spark to about 4.5, and enable closed loop so it wouldn't be rich (lower the spark is the richer it would run, closed loop would pull the fuel out) I'm using the AEM 30-0300 X-Series wideband

[SiriusC1024]

It's pretty odd that idle timing is that low. You got that idea from the 96 scan. Remember that it also commanded -22* when the throttle was applied.

Can we see if it likes a stock table? I turned off CL to make sure that it wasn't something to do with the narrowbands making spark jump from 15-25* for no apparent reason. According to the wideband fueling wasn't that far off in OL.

I just dealt with this on another vehicle (LT1). It liked way advanced timing of 32* at idle otherwise it would pop. That wasn't correct, either. Turned out that 2/6 plug wires were swapped. Is something similar the case here?

Did you maybe swap 2/5 on the coil pack? Are the plug wires routed differently 96 vs 97?

Yeah B2S1 drives lean as the O2's warm up. This indicates misfire. I see it in the misfire counter, too.

The 2/5 swap is a common mistake to make because that coil flips the sequence. I've done it before. In your head you may think 1,2,3 on one side of the pack and 4,5,6 the other side, but it's not like that. 1,5,3 then 4,2,6.

1-6-5-4-3-2 is the firing order. See how far apart 2 and 5 are in the order? Full crank revolution. It'll run ish. Charge ignites while the exhaust valve is open. Double check all the wires. Also, make sure it's not an ICM from something like a 3.1 or 3.4.

3800 coil pack.png

[SiriusC1024]

Any updates?