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8* of KR with cam, 3.4, FS IC, 90# springs. Nothings adding up (attached HPT logs).

94GrandPrixSE

94GrandPrixSE

New member
I'm completely lost here and im about to sell this thing, all this time and money into it and I cant even enjoy it because im always chasing something stupid.

Enough ranting, recently installed my XP cam (current mods are in my signature). Did some WOT pulls first few pulls saw 1-4* of kr so I tried going back to stock timing table. Worse... ended up seeing up to 8* of kr! Scared shi*less to even get on it I removed more timing and went from my 3.2 pulley to my old 3.4 and saw just about 10* of knock.

The reason this is in the "PCM tuning" category is because im still new to HP tuners, while I have done the basics such as fuel trims and ect im sure I could be overlooking something. Im thinking my knock attack or decay is just messed up or something it just doesn't look right on the graph. Also my AFR is reading a rich but healthy 10.5 ish at WOT so my injectors are not going static unless im missing something.

Another thing i noticed my MAF htz is reading 10,700 ish at the highest with the 3.4 but I was seeing the same numbers with the 3.2. am I somehow maxing out my maf? I thought max is 11,500? Before the cam and ported heads I had a max of 2kr on any heat soaked WOT run.

Any help is GREATLY appreciated, I hate being being a newbie tuner.

http://www.filedropper.com/3-3-17rerribleknock

http://www.filedropper.com/holy****_1

 


you could be lean due to lack of injectors, you should have 42's.

if you have your stock file still, load it up and see how it goes, you should be able to take stock timing all day long.
 
Im seeing 10.5 on the wide band at WOT. Both of those HTP logs I put up is on stock timing tables and thats where im getting the 8-10* of kr.
 
i cant even start to see them.

vac leaks? mis fires? plug wires on right? do a crank learn? cant hurt. hows your fuel pressure?

how about them injectors? stock still? if so just run the 3.4 pulley till you get 42's.
 
How would you even know if your injectors are good enough if you don't even log them??

You need to add the injector pulse width for both banks to your channel display. Then duty cycle will appear for you.
 


Scottydoggs said:
i cant even start to see them.

vac leaks? mis fires? plug wires on right? do a crank learn? cant hurt. hows your fuel pressure?

how about them injectors? stock still? if so just run the 3.4 pulley till you get 42's.
Click to expand...


No vac leaks, ton of misfires from the cam nothing at WOT anymore. Im running the 3.4 right now and still get almost 10* of knock. stock injectors but AFR is good
 
not yet, your boarder line maxing them out. 42's make it run so much better anyways. better spray pattern. and you can run down to a 2.8 on them easy. if you can beat this kr.

make sure nothings hitting, dp to sway bar. wheres the o2 sensor? is it hitting the fire wall maybe? what plugs and gap you running?
 
Scottydoggs said:
not yet, your boarder line maxing them out. 42's make it run so much better anyways. better spray pattern. and you can run down to a 2.8 on them easy. if you can beat this kr.

make sure nothings hitting, dp to sway bar. wheres the o2 sensor? is it hitting the fire wall maybe? what plugs and gap you running?
Click to expand...

I'm running 103's at .40 originally had .52 same results. Dp to sway bar is good. O2 sensor is in the normal area on sd headers and the firewall is punched out. Motor and trans mounts are all Polly.
 


I'm kind of in the same boat, except my car doesn't have near as much kr. I have spent quite a bit on this car, so I just keep driving it as a daily and don't really beat on it a lot. one way you could see if your injectors are running lean would be to lean out your afr. going from 10.5 to 11.5 afr will free up a lot of fuel, and the car will make more power.

another thing I noticed is that you are running an xp cam. on zzp's website they specify you need to disable engine code P0300 because the cam will make the car think it is randomly misfiring. I'm not sure if that could cause your kr, but it's real simple and easy to do.
 
all deleting the code does is tell the pcm not to show that p0300 code, its still gonna misfire at idle if the idle is to low.
 
SgtMarshal said:
I'm kind of in the same boat, except my car doesn't have near as much kr. I have spent quite a bit on this car, so I just keep driving it as a daily and don't really beat on it a lot. one way you could see if your injectors are running lean would be to lean out your afr. going from 10.5 to 11.5 afr will free up a lot of fuel, and the car will make more power.

another thing I noticed is that you are running an xp cam. on zzp's website they specify you need to disable engine code P0300 because the cam will make the car think it is randomly misfiring. I'm not sure if that could cause your kr, but it's real simple and easy to do.
Click to expand...

Maybe im wrong here but wouldn't that have the same affect as just having it set to run at 10AFR then when the injectors ran out it would automatically go lean (11.5 or whatever it may be)? My P0300 code is set to not report because of the dumb amounts of misfires it wont go into overdrive any other way.
 
Scottydoggs said:
all deleting the code does is tell the pcm not to show that p0300 code, its still gonna misfire at idle if the idle is to low.
Click to expand...

I get misfires all the way up to 3k rpm sometimes, I replaced everything ignition related no change. I can reduce the amount of misfires when I change my plugs to 104s but seems like a good sacrifice to have colder plugs as long as im not misfiring up top.

I could upload my tune .BIN if anyone thinks it will help.
 


A few things of note.
From what I can tell you are using the AFR calculation that the computer uses not what a separate wideband is indicating the latter being far more useful than the former.

Also since you are now tuning... some maintenance is in order if your Upstream oxygen sensor has about 50,000 miles or more on it you need to replace it. Those sensors Q overtime and they are a trusted sensor that the PCM assumes is working perfectly even if indicated otherwise.
The AFR calculation that the computer is doing is dependent on what the tune and sensors show it and a dirty and skewed oxygen sensor is about the biggest f****** that could happen in this area.

Stay away from Bosch o2s
 
Scottydoggs said:
did you start out with a canned tune? or you working from a stock file and tuning it for the first time?
Click to expand...

Both, Im using an overkill tune i purchased as my base and using a stock file with timing and such trying to get this knock to go away. Im still using the knock attack and decay from Wills tune because it looks safer, but on both timing tables im getting the same knock and ive tried taking 4 up to degrees out of the timing where im seeing this knock.
 
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