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-   -   2002 Bonneville SSEI Severe Knock Retard (https://www.gmforum.com/2000-2005-90/2002-bonneville-ssei-severe-knock-retard-277070/)

scruggelgreen 07-23-2008 12:54 AM

2002 Bonneville SSEI Severe Knock Retard
 
Hello All,
Recently i have been experiencing what i thought to be a loss of power out of my Bonneville SSEI, after using some fuel injector cleaner the problem was much better. But i was eager to see some real scan tool results. This is a test with AutoTAP and my laptop. I have currently 75000 miles on my car, running 92 octane fuel (BP Gasoline). No mods except for 180 Tstat and K+N air intake. If anyone can clue me into why the high knock retard that would be great!
Test 1 = on ramp on the freeway
http://fireball.dnsdojo.com/images/K...tard_Test1.bmp
Test 2 = Got off the freeway, turned around, on ramp again
http://fireball.dnsdojo.com/images/K...tard_Test2.bmp
Let me know if any of you have problems seeing these pictures

BillBoost37 07-23-2008 06:50 AM

Do us a favor and list out what the colors stand for. The legends etc are tough to read even at full size.

scruggelgreen 07-23-2008 08:26 AM

Absolutely,
Purple = Engine RPM
Red = Ignition Timing Advance
Green = Vehicle Speed
Blue = Knock Retard

Danthurs 07-23-2008 08:54 AM

Ok, this is what I see. No KR in 1st gear, then you start climbing in 2nd and have a spike at the 2nd-3rd shift point. Were you at WOT during these tests? I would start looking at the tranny, my guess is it's making noise that the sensors hear as knock. A shift kit should help clean this up a LOT. I went from 7*+ to about 2* after installing a shift kit. Another thing to check is your mounts, make sure there not loose or worn.

If you look at your timing line, it dropped at both shift points, this is normal to protect the tranny. A shift kit and a tuned PCM will correct this by upping the pressure and shortening the shifts. Intense sells a good kit for about $150 I believe, takes about 2 hours to install and the only tool you need is a inch pound torque wrench.

BillBoost37 07-23-2008 09:24 AM

I'm right there with Dan on what he's seeing. Knowing the way our drivetrains work etc, I wonder if you have the ability to log misfires by cylinder? If so, let's look for bad plugs or wires as well.

Check fuel pressure under load. I've found a few cars that begin to starve for fuel, but 1st and 2nd go by quick enough that it doesn't show until 3rd.

Danthurs 07-23-2008 09:29 AM

I thought that as well Bill, but it seemed to be starting a little early for a lean condition. Which is why I'm thinking tranny. Check fluid as well, tranny noise sounds like knock to the sensors.

I would also suggest pulling each plug and making note of how each looks and what cylinder it came from. You want a nice gray/white look to the plugs. Not a black/shinny look. A bad wire or plug will have just that one bad plug. A bad coil will have a pair matching that coil.

Here's my scan.
http://www.thurs.net/dan/personal/bo.../misc/run2.jpg
Green= KR
Yellow=RPM
Red=boost
White=coolant temp

BillBoost37 07-23-2008 09:36 AM

You have a good point there Dan. RPM might be low, I'm kinda used to how quick my modded motor revs and was thinking along the lines of how another buddy with a GP didn't see fueling issues until hitting 3rd.

It would good to check, but wouldn't go out of my way to test if other items are spotted first.

Danthurs 07-23-2008 09:49 AM

I'm looking REAL close at the scan here, shift 1 is about 42MPH and shift 2 is at about 75MPH. So no PCM tune has been done. So he's running stock tranny pressure.

Looks like he pulled 13* on the first shift point, and about 10* on the 2nd. He starting getting KR half way threw 2nd. Could be fuel starving. Fuel filter change might be in order. Another thing to check is plug gap. What plugs you running, and what gap are they at. I suggest gapping at .055 instead of the stock .065

So after very close inspection I believe it's a combination of 2 things, tranny and fuel. Mostly tranny.

scruggelgreen 07-24-2008 01:19 PM

Wow you guys are amazing at how much you can tell from the graphs. I just replaced the fuel filter last night and it was so dirty that when looking inside of it, you could barely see the filter element. It was full of a brown sludge (Probably from the bottom of the gas stations fuel tank). I also used my K + N recharger kit to clean the air filter last night. So tonight i am going to go out and run the same tests to see what if anything has changed. To answer BillBoost37's question i do have the ability to log misfires on each individual cylinder. I will also do that tonight and see what i come up with. Thanks again for all of your help and i will be getting back to you later tonight......

scruggelgreen 07-24-2008 01:25 PM

Oh and i forgot to answer Danthurs, i am running irridium spark plugs. Honestly its been about two years and 40000 miles since i replaced them so i do not remember the brand name. Looking around on this site i noticed alot of you use autolite platinum spark plugs. I think i will do a plug and wires job soon with Autolite.


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