ChevyNo1

WTF??? What do I do next? I suppose someone is gonna tell me now that I need a new PCM . . . funny these codes didn't get set until I got LS1-Edit programming!!

Somebody else has had this happen to them surely . . . what did you do? I can't go running around in an FI car with no knock sensors!!

- Dug

Slowhawk

iTrader: (12)

I wouls suspect too much timing or engine contact to body giving false knock.

NicD

iTrader: (7)

Only problem being the second the car fires up and gets into closed loop, it sets the codes immediately. This has happened on a few others cars that I have personally seen, and a few on the net. It does seem related to LS1edit somehow, but I don't see how doing minor changes with LS1edit causes this. But the only thing in common between all the cars that throw these codes seems to be after they use LS1edit. I brought this up over a year ago as a possible error in LS1edit.

ChevyNo1

Slowhawk . . . it's not false knock. It's the codes set that say my sensors are toast. So when I go WOT, it automatically pulls 4 degrees no matter what. I either get 0 or 4, nothing in between.

MIGHTYMOUSE

iTrader: (59)

what codes are they specifically?

there is a way to test the knock sensors.. however i have forgotten. but can be done with a multi meter.

if it didnt happen until you edited the car, put it back to stock and see if it goes away.

i have had two rear knock sensors go bad on my 98.. this last time i made sure they were sealed from water.

ChevyNo1

MM, I don't have the codes right in front of me . . . but I believe they are the low sensor input or voltage or something to that effect . . . and yes, they can be tested with a multimeter, and yes, we tested them and the voltage was increasing when I rapped on the heads. So they ARE working. The PCM thinks they're not. I can't really go back to stock because I have 42lb injectors, the car would run like **** wouldn't it?

- Dug

MIGHTYMOUSE

iTrader: (59)

are the pins into the computer getting the signal? continutity check between them.. not just from the replaced plugto the wire?

MYTURBOT/A

The car don`t have to run good with the stock tune, it just has to run long enough to see if the codes come back. I`d try taking it to the dealer have them flash it back to stock so you have fresh non corrupted tune then reread with edit do your adjustments and reflash your car. Just a suggestion.

ChevyNo1

MM, yes, we checked it at the pins on the PCM, and it seemed fine to us. FWIW, my buddy that tunes my car had the same thing happen to his car. However, we was able to delete the codes in LS1-Edit on his car ( 99+ ) and his sensors were still reading. It appears on the '98 cars it turns them off completely.

Hmmmm, I just might do that. How much does a dealer charge to reflash? Would that be cheaper than getting Ken Kelly at LS1-Edit to send me a new PCM?

- Dug

Blackbird

you could probably get them to flash it for free if they are nice.

Blackbird

oh here's a question. you downloaded and saved your original computer flash right?

why don't you just put it back and see if it helps at all.

dissonance

dealer charged me around $30 to do it only took 30 min. i think most charge $1 min what a rip? but where else can you get it done?

Pro Stock John

iTrader: (34)

Why not redo the wiring, the wiring might be melted or partially pulled.

Reflashing the pcm should not help, you are setting a code.

KOOL C5

iTrader: (2)

I had the same problems after I used Edit. Version 1.3 has knock volume.
I increased volume by 10%(110). I started with 15% then went to 10%. I tried 5% and the 327 and 332 codes came back. Hope this helps.
Tom Hall

NicD

iTrader: (7)

That is an interesting find Tom, I think we will try that tomorrow. I am wondering if that knock volume table is in the 99+ PCMs and Ken just hasn't found it yet, or if it is specific to 98s only. I think I will contact Ken Kelley and ask him if it is possibly in the 99+ PCMs. Just curius, does your car still get knock retard having your knock volume increased by 110%?

KOOL C5

iTrader: (2)

I haven't seen any KR with the increase in volume. I use 104 race fuel all the time and don't drive on the street much. I do feel better that the sensors can be on. I was getting 9.9 KR when the codes came on. I hope it's working. Good Luck.
Tom

JimMueller

iTrader: (9)

I just had the same problem. I left the new harness wires too long and they got pinched when I re-installed the manifold.

I had to perform some surgery, but the problem has disappeared after repairing the wiring. Perhaps you've already checked this, though.