can't find hp tuner tech

**maviation** · 04-20-2008, 07:43 PM

have a after market ls1 by bill mitchell (world products) just got the car in march, ran great. 1/4 m avg mid 10s no nos. got ticket doing 170.
now car is running real rich . codes are o2 left bank. change both o2s, still same codes. car is now starting to stumble and all at once it go away,but still runs to rich. i mean leaves black marks on ground at the turn downs.
paid to much for this old x-year 1 proto type 98 t/a

**bigboykilroy** · 04-22-2008, 06:03 AM

Maybe rings went bye bye, 170mph is fast and hard on the engine.
Do you have a copy of the HP Tuner file he loadeding to your PCM?
I have HP Tuners and a 98 and can look at the tune for you.

**Eagle** · 04-22-2008, 09:59 AM

Rich just @ idle, or all throughout the RPM range?

Checked ALL your plugs at all yet?

Any SES light or codes being thrown?

Do you have a wideband? Whats the AFR?

If the car DID NOT do this before and it wasn't tuned or modded since, then looking at the tune is a waste of time.

-Eagle

**bigboykilroy** · 04-22-2008, 04:07 PM

It is possible once the car "learned" from the tune it moved from the origional tune. I have seen it before.

**Eagle** · 04-22-2008, 06:14 PM

Originally Posted by bigboykilroy

It is possible once the car "learned" from the tune it moved from the origional tune. I have seen it before.

moved eh? resetting the PCM would fix that if it were the case...

**Frost** · 04-24-2008, 04:29 AM

Originally Posted by bigboykilroy

It is possible once the car "learned" from the tune it moved from the origional tune. I have seen it before.

The only things the PCM learns is fuel-trimming and idle air trims. It doesn't change itself.

**Eagle** · 04-24-2008, 06:07 AM

Originally Posted by Frost

The only things the PCM learns is fuel-trimming and idle air trims. It doesn't change itself.

Exactly. Thx for confirming, Frost.

-Eagle

**bigboykilroy** · 04-24-2008, 03:27 PM

and your point being what? He still has a problem, running rich, i would still look at the tune the pcm is running to see why it is commanding so much fuel.

**Frost** · 04-24-2008, 05:54 PM

Originally Posted by bigboykilroy

and your point being what? He still has a problem, running rich, i would still look at the tune the pcm is running to see why it is commanding so much fuel.

My point was the PCM hasn't changed its own tune as was suggested. Maybe you didn't read all of his post. His car ran great, and the tune has not been changed since. If the PCM were "commanding so much fuel" it would never have run well.

Maviation - what are your exact codes? Sounds likme they were perhaps heater codes for the O2s. If there is a problem with the heater circuit, it could even be as simple as a blown fuse that powers them. All of this is outside of the O2s that you replaced. If they have an issue, the car can be forced to run open loop, and depending on how you were tuned, this could make the car run like crap (except WOT).

**bigboykilroy** · 04-24-2008, 08:08 PM

"Mavation" stated he got the Car in March 08. did some 1/4 runs on it now it runs like crap and ran the car going 170 mph..... its April so maybe like 60 Days on his tune if that, if the car was ran at WOT right after the flash who knows where it is at, hense looking at the whole PCM in the car to see what its doing. Well lets see what "Mavation" has to say....

**Frost** · 04-25-2008, 08:45 AM

If you understood what closed loop was and how it worked, you'd understand that this isn't a PCM issue. Closed loop constantly corrects to stoich based on O2 feedback. If there are no O2s, there is no closed loop operation and this is the result; fat idle and cruise.

**bigboykilroy** · 04-25-2008, 03:22 PM

Wow u dont have to be a prick, Hook up a scanner and see what the tune/PCM is doing. Something is causing the PCM to feed that much fuel. Im sure the guy doesnt even know what the car is tuned for, that is why i asked if he had a copy of the tune. That is what we do for our customers. Make them a copy of the before and after and burn it onto a cd for them.

**mrr23** · 04-25-2008, 06:43 PM

Originally Posted by bigboykilroy

Wow u dont have to be a prick, Hook up a scanner and see what the tune/PCM is doing. Something is causing the PCM to feed that much fuel. Im sure the guy doesnt even know what the car is tuned for, that is why i asked if he had a copy of the tune. That is what we do for our customers. Make them a copy of the before and after and burn it onto a cd for them.

as you can see, the question was asked if the tune could move away from the original program. being a tuner yourself, you know that the tune cannot change itself. it is hard programmed into the PCM. so, frost was letting him know the original tune doesn't change.

Originally Posted by bigboykilroy

It is possible once the car "learned" from the tune it moved from the origional tune. I have seen it before.

Originally Posted by Frost

The only things the PCM learns is fuel-trimming and idle air trims. It doesn't change itself.

**mrr23** · 04-25-2008, 06:48 PM

Originally Posted by bigboykilroy

Wow u dont have to be a prick, Hook up a scanner and see what the tune/PCM is doing. Something is causing the PCM to feed that much fuel. Im sure the guy doesnt even know what the car is tuned for, that is why i asked if he had a copy of the tune. That is what we do for our customers. Make them a copy of the before and after and burn it onto a cd for them.

so, with what i said above in mind, what would looking at the tune itself do, if it was running fine when he first got it? the tune itself isn't the problem. the OP got codes for his left bank o2s. replaced and still has an issue.

yes, the vehicle needs to be scanned while running to see what the PCM is seeing and what it is doing to 'correct' the current issue.

**Frost** · 04-25-2008, 08:24 PM

Not trying to be a prick, just didn't want to make the guy doubt his cal and spend money having a perfectly fine car "retuned". What he is describing is either a heater circuit failure on the car side or other o2 wiring issue(s) on the car side. His car is no doubt in open loop, and unfortunately, most cars don't have a calibrated VE or MAF as a part of their tune. It will have been injector tuned to be trimmed negative all over (most likely) and when that is combined with the really rich commanded values in the OL table (really that table is FAT OE) the car will be rich all around. A scanner would be useful to look for ANY O2 activity, but it really sounds like it is in the wiring. It will do this even if the issue is just on one side, so again a scanner would be useful for this as well. I wasn't saying that a scanner wasn't useful, just that this is hardware issue more than a software issue.

Not trying to be a prick, just want the info here to be accurate, many people are reading.