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Old 10-23-2004, 11:31 PM   #1
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Default Experiements = WTF!

Ok I'll start from the top....

Last night I installed a new o2 thinking it would cure my maxed L-trims...well no.
I go to the track today and while driving there I notice my L-trims dipping down more than usual when I got on it. This is good I thought, considering I didn't even reset the computer.
Well the track rained out so I parked the car in the barn and started shotguning my L-trim problem (yeah, i don't care anymore). I started by unhooking the battery to allow the PCM a good 30 minutes to reset itself. While that happened I blocked off the EGR with a plate and let the EGR tube suck in clean air from the engine compartment (will install a mini filter soon enough). I started the car up and YAY the L-trims maxed out over a matter of seconds. Then I took the car for a drive and noticed my KR was up to 5!!!!

I gave it a few more WOT shots around town and soon it was down to .2, .3, sometimes .5. This is good, very good because I usually get .7 to 1.5. However it wasn't all fun and games. My timing sux. Saw an average of 14 degrees and at one point I swear I saw a negative number out of the corner of my eye!
Is this the PCM relearning my engine or did blocking off the EGR mess something up I'm unaware of?

PS: I don't wanna hear any negative input on bypassing the EGR because it will blow a valve. We have been over this a million times and this is strictly an experiment to see if the EGR helps or hurts KR.
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Old 10-23-2004, 11:52 PM   #2
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I would expect that result from an EGR delete on a non-intercooled engine. The EGR actually decreases combustion temps by displacing air. Put the EGR back on, and your KR should return to normal.
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Old 10-24-2004, 02:19 AM   #3
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Quote:
Originally Posted by willwren
I would expect that result from an EGR delete on a non-intercooled engine. The EGR actually decreases combustion temps by displacing air. Put the EGR back on, and your KR should return to normal.
That was kinda my thinking reading your post Kyle, maybe do some testing tomorrow, then unblock the EGR and see what happens?
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Old 10-24-2004, 01:32 PM   #4
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Wait now I think we are confusing eachother. If you read my original post my KR went down. However today it'* back up a little bit. Also my timing just stinks...nothing over 14. Think no EGR is causing this?

Strange thing is after blocking the EGR and installing a new o2 my L-trims still max out, but at WOT they zero in on 0.0
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Old 10-24-2004, 06:45 PM   #5
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Installed the EGR tube again, then reset the PCM for only 5 minutes and started her up. Well it'* running just like it was. Something happened either when I reset the PCM or touched the EGR because my timing is horrible. My guess is that its still gotta relearn everything. The semi-good news is that when I go WOT the L-trims hit 0.0 and stay there, but if I let off the gas they go back up to 16.4. I re-torqued the front header for now, but no changes....leak must be elsewhere.

Anyway, I need those with performance PCM to fill me in on if it takes time for the timing to calibrate itself after you reset the PCM? Because before yesterday I was smacking upwards of 19 degress, now I see anything from -3 to 14.
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Old 10-25-2004, 12:49 AM   #6
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have you talked to INTENSE about this at all?
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Old 10-25-2004, 08:26 AM   #7
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Quote:
Originally Posted by Allmachtige
Installed the EGR tube again, then reset the PCM for only 5 minutes and started her up. Well it'* running just like it was. Something happened either when I reset the PCM or touched the EGR because my timing is horrible. My guess is that its still gotta relearn everything. The semi-good news is that when I go WOT the L-trims hit 0.0 and stay there, but if I let off the gas they go back up to 16.4. I re-torqued the front header for now, but no changes....leak must be elsewhere.

Anyway, I need those with performance PCM to fill me in on if it takes time for the timing to calibrate itself after you reset the PCM? Because before yesterday I was smacking upwards of 19 degress, now I see anything from -3 to 14.
100 miles is the general rule for pcm to learn everything. You may want to email or call Scott on this leak issue.
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Old 10-25-2004, 08:22 PM   #8
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I emailed Scott about the timing issue and he said the PCM just needs time to relearn everything. Once you get a scantool you really start paying attention to your car more.

As for the leak, I'm still checking out the data. Now after the new o2 sensor install it appears my L-trims will hit a solid 0.0 at WOT, but jump back up to 16.4 when I let off the gas. However, sometimes when I come to a stoplight I notice the L-trims will hover from 11.4 to 12.5 to 13.3, then back down to 11.x and finally stay right in that area. I've noticed this only a few times, but for the most part they shoot right back up to 16.4.

I retorqed the front header (rear can wait...pain to get to), from what I can see my crossover clamps are TIGHT. EGR tube is in there pretty darn good, even used GM red gasket maker around the flange. But, I ripped some of the SC gasket a month ago when I took the snout off and installed a ZZP coupler. Why this would cause a problem only after I did headers is strange, so I tend to rule it out. Either way I need new bearings soon so the whole SC is coming off and I'll replace the gasket and o-rings in the process.

My cig lighers blew out not to long ago (fuse probably went, have yet to check) and I'm curious if something else vital ran off that system, but I doubt it.

Give me a week and I'll start crying for help like a little 12 year old.
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Old 10-26-2004, 05:01 AM   #9
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Quote:
Originally Posted by Allmachtige
I emailed Scott about the timing issue and he said the PCM just needs time to relearn everything. Once you get a scantool you really start paying attention to your car more.

As for the leak, I'm still checking out the data. Now after the new o2 sensor install it appears my L-trims will hit a solid 0.0 at WOT, but jump back up to 16.4 when I let off the gas. However, sometimes when I come to a stoplight I notice the L-trims will hover from 11.4 to 12.5 to 13.3, then back down to 11.x and finally stay right in that area. I've noticed this only a few times, but for the most part they shoot right back up to 16.4.

I retorqed the front header (rear can wait...pain to get to), from what I can see my crossover clamps are TIGHT. EGR tube is in there pretty darn good, even used GM red gasket maker around the flange. But, I ripped some of the SC gasket a month ago when I took the snout off and installed a ZZP coupler. Why this would cause a problem only after I did headers is strange, so I tend to rule it out. Either way I need new bearings soon so the whole SC is coming off and I'll replace the gasket and o-rings in the process.

My cig lighers blew out not to long ago (fuse probably went, have yet to check) and I'm curious if something else vital ran off that system, but I doubt it.

Give me a week and I'll start crying for help like a little 12 year old.
Kyle,

Looks like the new O2 has done some good and put you in the correct direction, now you need to get those Ltrims as close to zero or -5% as possible at idle, cruise and you are all set. Possibly a Mini-Afc 2.0 or an ICCU will do this for you? Remember my car was around +10-+11% at idle, and +2-+3% at cruise before I got the AFC and started tuning the vehicle.

Your L-trims will always go to 0% at WOT, the PCM has built-in fuel curves for WOT and relys on the O2 readings. The reason why you want to get your L-trims at idle,cruise to 0% - -5% is because if your L-trims are positive and you go WOT the PCM will compensate and you could possibly get some unneeded knock or reduced timing.

I just scanned a neighbors vehicle last week, it was his dads car a 99 Cadillac SLS. He was throwing the same codes as you, cept he was also getting a P0164 (Fuel Lean Bank 2). His IAC counts were normal, and everything checked ok that didnt show the problem as a vacuum leak. He went to Autozone and picked up 2 new O2 sensors (Told him not to get Bosch sensors, but he is selling the car and just wanted the light to go away), anyways after getting them installed his problem was solved Car had only 58,000 miles....
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Old 10-26-2004, 07:54 PM   #10
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I'm still getting 16.4 at idle, or whenever I let off the gas.

Joel, tell Sean to check his PM'*.
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