Lack of Timing Advance...Lots of KR...Slow - UPDATE 9-9-07
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From: Twin Falls, Idaho

I'm getting 1-4* of KR with a 3.4. Actual Timing reduction is 8*, meaning at WOT, I am seeing numbers around 7-9 degrees of timing advance. This is nowhere near what it should be (15.5* or so)
My 98 has no problem running a 3.4 without KR, heck I can throw a 3.2 on with pump gas and only get 2* or so and that equates to 13* of timing.
Is there some difference between the 98 and the 01 PCMs? Or is this normal on a 00+ without exhaust mods?
I just found it was odd I could run a 3.4 with an entirely stock exhaust on my 98 yet I cant on my 01 peacefully.
I guess I will start by changing the fuel filter first, then look at installing headers and a high flow cat, and eventually move back to replacing the fuel injectors and the PCM as my next plans of attack. Anything else I should look at?
My 98 has no problem running a 3.4 without KR, heck I can throw a 3.2 on with pump gas and only get 2* or so and that equates to 13* of timing.
Is there some difference between the 98 and the 01 PCMs? Or is this normal on a 00+ without exhaust mods?
I just found it was odd I could run a 3.4 with an entirely stock exhaust on my 98 yet I cant on my 01 peacefully.
I guess I will start by changing the fuel filter first, then look at installing headers and a high flow cat, and eventually move back to replacing the fuel injectors and the PCM as my next plans of attack. Anything else I should look at?
how bout KR on a 3.8 pulley, that is what my car is doing....about 1-2* of KR for me
the 00+ are total opposites when they are concerned with the TM and the settings in teh car
your are really having problems if the car is only seeing 9* of advance....you should be running at 14-14.5* of advance
the 00+ are total opposites when they are concerned with the TM and the settings in teh car
your are really having problems if the car is only seeing 9* of advance....you should be running at 14-14.5* of advance
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From: Twin Falls, Idaho

Originally Posted by 1993 SLE
how bout KR on a 3.8 pulley, that is what my car is doing....about 1-2* of KR for me
the 00+ are total opposites when they are concerned with the TM and the settings in teh car
your are really having problems if the car is only seeing 9* of advance....you should be running at 14-14.5* of advance
the 00+ are total opposites when they are concerned with the TM and the settings in teh car
your are really having problems if the car is only seeing 9* of advance....you should be running at 14-14.5* of advance
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From: Red Deer, Alberta WCBF_'05_Survivor WCBF_'06_Survivor WCBF_'07_Survivor

I know you are not using an Intense PCM, but on their site I'm sure I remember reading that a couple degrees of kr is normal.
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From: Twin Falls, Idaho

80* outside, much cooler than before. The car is running the same. I get maximum of 12* off the line timing and halfway thru second it pulls 3* or so of KR brining my timing down to 9, then the KR goes down but then the timing hits 7 right after it shifts out of 2nd.
7* - WTF with a 3.4. I never scanned the car stock.
I've done the following:
Replaced Plugs and Wires, checked resistance on both prior to installation to insure they were identical, they were
Replaced Fuel Filter with GM OEM
Reset the PCM overnight
Autolite 104s - I've tried gapping at 0.48, and 0.53ish same issue with timing
New FPR in last year
I'm running the INTENSE FWI and my iat temps in the fender are VERY close to ambient, I have cut out the bottom of my fender to allow for colder air.
Fuel Pressure is right at 50 on a supercheap guage.the fuel pressure under load. The FPR is brand new due to the recall.
I'm curious what other timing advance numbers other 00+ SSEi owners are pulling with stock exhaust and stock PCM....maybe this is normal?
7* - WTF with a 3.4. I never scanned the car stock.
I've done the following:
Replaced Plugs and Wires, checked resistance on both prior to installation to insure they were identical, they were
Replaced Fuel Filter with GM OEM
Reset the PCM overnight
Autolite 104s - I've tried gapping at 0.48, and 0.53ish same issue with timing
New FPR in last year
I'm running the INTENSE FWI and my iat temps in the fender are VERY close to ambient, I have cut out the bottom of my fender to allow for colder air.
Fuel Pressure is right at 50 on a supercheap guage.the fuel pressure under load. The FPR is brand new due to the recall.
I'm curious what other timing advance numbers other 00+ SSEi owners are pulling with stock exhaust and stock PCM....maybe this is normal?
From what i read on here it'* fairly common to be getting KR with a 3.4 on stock manifolds and downpipe/cat. I had the PEM'* and Intense PCM on for months before i did the 3.4 so i can't be sure but that'* what the general consensus seems to be. Have you checked closely for vacuum leaks? I'm pretty sure that'* what my KR came down too as i'm now back to 14.5*-15* of timing from about 11 or 12.
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From: Twin Falls, Idaho

Originally Posted by 1994se
From what i read on here it'* fairly common to be getting KR with a 3.4 on stock manifolds and downpipe/cat. I had the PEM'* and Intense PCM on for months before i did the 3.4 so i can't be sure but that'* what the general consensus seems to be. Have you checked closely for vacuum leaks? I'm pretty sure that'* what my KR came down too as i'm now back to 14.5*-15* of timing from about 11 or 12.
a large vaccum leak that may contribute to the boost bypass valve not closing all the way would probably raise my timing and reduce my KR since I'm the car would not be pushing as much boost. at least thats what I thought.
However I'm pushing normal boost levels, the same as my 98 right around 9psi. With that car it had no KR and 14-15* of timing all the way up until 3rd then KR would kick in.
I completely forgot that you're driving at everest like altitudes as well so that 3.4 isn't producing as much boost as it would if you lived in say Illinois
. Maybe it does have a lot to do with the PCM and TM and whatnot. Hell 1993 SSEi is getting up to 2^ of KR stock so it'* possible.





