o2 respond graph. which one looks right to you?

[Cringer]

how do I check that?

how do I check that?


I found a log all the way back from 2017 and that side was still jagged.

not that it couldn't be an injector or something too

Right click the channel in the scanner and max out the polling speed
poll me hard daddy.jpg

[???]

both were at 200ms 5hz. I moved both to 10ms 100hz

I didn't get to start it and run to see if there was a change. but since they both matched, I doubt it? last night I have the original gm plug wires still, so swapped all 4 on that bank, since nnimber 5 cyl did have one or 2 missfire counts, swapped it to bank 2 side and swapped coil packs. no change.

I will pick up some new plugs tomorrow, maybe do a compression check while for the heck of it. easy enough and hopefully rule out a valve or something.

will see what happens. literally found one of my first logs from getting hpt in 2017 and that bank is jagged back then. I just never looked at it or thought anything of it I guess.

[ns158sl]

Remember there is limited bandwith for polling. So all that does is prioritize polling rates. In other words, if you already have a bunch of channels at too fast of a raster the others will suffer. A lot time you wont be able to quickly see that being that HPt will interpolate data. Best way to see how it polls is export the log into excel or something like that and you can really see how slow things are polling. Thats why I never understood when people migrated from gen3's to the Gen4 and Gen5's and would add all the channels, lol.

[Cringer]

Remember there is limited bandwith for polling. So all that does is prioritize polling rates. In other words, if you already have a bunch of channels at too fast of a raster the others will suffer. A lot time you wont be able to quickly see that being that HPt will interpolate data. Best way to see how it polls is export the log into excel or something like that and you can really see how slow things are polling. Thats why I never understood when people migrated from gen3's to the Gen4 and Gen5's and would add all the channels, lol.

Because Gen3's were very slow and had limited bandwidth as compared to the Gen4/5.

[Alvin]

If the polling the is the same it might be a good idea for fresh sensors. Change both at the same time.

I've replaced aged sensors simply cause they look exactly like yours do and it normally is the fix. This is assuming you checked your heater fuse.. not all of them will set a DTC for a heater circuit cause the fuse popped.

[???]

update.

polling didn't help, so I put it back to default 200ms.

replaced plugs and wires, didn't help. replaced o2 sensor, only on that side since I can't get to the other bank o2 without removing the header. replaced the o2 extension cable. no change. but with the extra I was able to plug them into the opposite sides harness plug. amazing how quickly the trims go crazy and it runs like crap. but I was able to use the scanner buttons to keep it in only loop and reset the trims enough that it would idle. giving it a little throttle off and on was able to see the o2 switch a bit and the bank 2 graph showed jagged line and bank 1 was smooth. so I think I can rule out wiring in the harness to ecm.

oh, did a compression check on that side, all 4 holes are within a few psi.

so I guess fuel injectors are the only thing left?car has 110k on it, but my guess is it only had about 80k on it in my oldest log.


edit, yes. heater fuse. looked like only one for all 4 and it was good and had power

[ns158sl]

Because Gen3's were very slow and had limited bandwidth as compared to the Gen4/5.

Still very limited. Log what you need.

[edcmat-l1]

but with the extra I was able to plug them into the opposite sides harness plug. amazing how quickly the trims go crazy and it runs like crap. but I was able to use the scanner buttons to keep it in only loop and reset the trims enough that it would idle. giving it a little throttle off and on was able to see the o2 switch a bit and the bank 2 graph showed jagged line and bank 1 was smooth. so I think I can rule out wiring in the harness to ecm.

As I said before, 100% it's a miss on bank 1. Whether it's injectors, coils, plugs, wires or mechanical, it's a misfire on that bank.

[???]

As I said before, 100% it's a miss on bank 1. Whether it's injectors, coils, plugs, wires or mechanical, it's a misfire on that bank.

not disagreing, I'm just running out of things to check to repair it. I'm going to pull the injectors, check spray pattern and swap banks. if that's not it. I'm kinda out of ideas.

I do have a clone tech 2 that I forgot worked on this car. I might pull up the o2 on it and graph the signal. I'm not sure what kinda data rate it is thou.

[???]

OK, I'm that's that absent-minded and was about to pull the injectors out and remember to check the ohms. yep, number 5 reading 80ohm, rest at 12.8. was trying to do simple tests first and forgot the most simple lol.


anyone got any recommendations on the nicest injector these days? and if I go aftermarket is all I need to do is to plug in the offset voltage provided and changed the lbhr to match in the tune? or I pretty much need to retune for any new injectors besides oem.

I see ifc has a set of 50s for 440$. I think 50s would more than cover any mods I'd do to this short of boost. but then again 42s probably would too.

[edcmat-l1]

I'd run exact GM replacements. That way the additional work required is zero and chance of introducing another variable, also zero.

[Cringer]

OK, I'm that's that absent-minded and was about to pull the injectors out and remember to check the ohms. yep, number 5 reading 80ohm, rest at 12.8. was trying to do simple tests first and forgot the most simple lol.


anyone got any recommendations on the nicest injector these days? and if I go aftermarket is all I need to do is to plug in the offset voltage provided and changed the lbhr to match in the tune? or I pretty much need to retune for any new injectors besides oem.

I see ifc has a set of 50s for 440$. I think 50s would more than cover any mods I'd do to this short of boost. but then again 42s probably would too.

OEM L96 injectors can be had cheap on eBay! 52 lb/hr. It is what I am running now. Read the thread....they will require a few pieces from ICT Billet to work.
https://forum.hptuners.com/showthrea...l=1#post714055

[???]

OEM L96 injectors can be had cheap on eBay! 52 lb/hr. It is what I am running now. Read the thread....they will require a few pieces from ICT Billet to work.
https://forum.hptuners.com/showthrea...l=1#post714055

thanks for the link, I was trying to find some newer info on these.

like everyone I'd be all in on them for the price, I do have e85 near by and no cats. so while I wouldn't do it for hp, the lack of smell would be more than enough motivation. but I see ls sites selling them for 250$ a set, and ebay from $30 to 100$. so many fakes these days. do you know of any forsure legitimate ebay sellers?

since I don't feel like stock gm injectors have a high failure rate, I expect them to be the last thing to fail on stock cars. I've owned a few gm cars over 200k. I'm half thinking ordering a stock oem off rock auto for 60$, clean the other 7 and throw them back in.

so torn haha

[Cringer]

thanks for the link, I was trying to find some newer info on these.

like everyone I'd be all in on them for the price, I do have e85 near by and no cats. so while I wouldn't do it for hp, the lack of smell would be more than enough motivation. but I see ls sites selling them for 250$ a set, and ebay from $30 to 100$. so many fakes these days. do you know of any forsure legitimate ebay sellers?

since I don't feel like stock gm injectors have a high failure rate, I expect them to be the last thing to fail on stock cars. I've owned a few gm cars over 200k. I'm half thinking ordering a stock oem off rock auto for 60$, clean the other 7 and throw them back in.

so torn haha

This is the seller I went through. No complaints.

https://www.ebay.com/itm/27442490602...mis&media=COPY

[???]

OK, you got me.

ordered a set and got the adapter kit coming.

thanks.

[???]

a guy off the corvette board offered me a low mileage stock ls set for 100$. so I went ahead and got those too. I'll clean and throw them in first to make sure it's all good and then use the 50s later when I get a e sensor wired in

[TheMechanic]

I'll agree with the misfire. Reason is that fuel trims are up on B1 compared to B2 and it is very "spikey" at the tops rather than a smooth rounded top transition.

[tonn0297]

Im trying to read mine as well, is the main thing to look for the "spikes"? car drives great but this thread got me wondering
vmplayer_C1RcyDbsIz.png

[???]

Im trying to read mine as well, is the main thing to look for the "spikes"? car drives great but this thread got me wondering
vmplayer_C1RcyDbsIz.png

I'm no expert for sure but I'd have never known without seeing the jagged signal.

for mine one is nice and smooth all the time and the other was all over the place. I see yours has very little ones on each bank in different side. but I don't know if that's what a cam looks like or what's done to your car. mine is pretty much stock, cam and all. even went back to a zo6 air intake box to get rid of the maf fluctuations that annoyed me at cruise. so it should be smooth

[tonn0297]

I'm no expert for sure but I'd have never known without seeing the jagged signal.

for mine one is nice and smooth all the time and the other was all over the place. I see yours has very little ones on each bank in different side. but I don't know if that's what a cam looks like or what's done to your car. mine is pretty much stock, cam and all. even went back to a zo6 air intake box to get rid of the maf fluctuations that annoyed me at cruise. so it should be smooth

mine is 100% stock as well, tho gen V, but that will not change O2 response graph. Ive not heard about seeing misfires like that so its kinda intruiging, i may try and log o2 alone at max pullrate and see if that changes the view, sometimes hpt is very bad at showing stuff