I have an Actron Superscanner. Could any of the available parameters that it can moniter give an idea as to what may be wrong with my car? One thing that I've noticed is that my gas mileage is pretty low, even with brand new O2 sensors. If the Actron isn't good enough, then where can I go to get it scanned? A dealership?

 

What parameters does that scanner let you look at?

 

These are the available scanning parameters:
Absolute TPS (Throttle percentage)
Engine RPM
Calculated Load
MAF (Pounds/minute)
MAP (Hg)
Coolant Temp (Degrees F)
IAT (Degrees F)
Ignition Timing Advance (Spark advance to add from base engine timing)
Second Air (If AIR is on or not)
LT FTRM1 (Long Term Fuel Trim Bank)
ST FTRM1 (Short Term Fuel Trim Bank)
LT FTRM2
ST FTRM2
O2S11 (Oxygen Sensor Output Voltage)
ST FTRM 11
O2S12
O2S21
ST FTRM 21
O2S22

 

sounds like a broken/bent pushrod on drivers side, prolly bent. get a big screwdriver, crank the car, put head of screwdriver on valve cover and handle to ear, listen for your noise. Clanking or tapping......remove valve cover.....no noise, get stethescope, try again, just to be sure. Check passenger side also, as sometimes the noise can be deceiving.

Billy D.

 

If you are really serious about getting the most out of your headers, you'll need to flog the primary as well as collecter tube lengths. This is obviously easier (to accomplish) with adjustables.

 

What do you mean by "flog" the primary?

 

Not only can the collecter length be tuned/adjusted/tested, the primary lube length can be as well. To some, this appears to be a lost science.

 

TTT- Anyone have any other input about this? Would the readings from my Actron help anyone out with figuring out whats wrong with my baby?

 

Check your rockers, if they are not aligned properly, it could be as bad as having misses in your sparks, or worse! But i feel for you dude, when you are expecting something, to come up short like that, happened to me.

Now i'm afraid to go to the track after my rebuild.

 

well, ive got an M6 and my car w/ similar mods and its running a solid 5mph better then you in the 1/8. ive got 275rwhp. when i put my headers on my knock went nuts, Brian at pcm4less fixed that. i bet when you get the knock sensor turned off itll run good. my times and stuff are in my sig.

 

TTT- I know I had started this thread a long time ago but I was just wondering if anyone else had any input. I think I'm about to get a tune by MadZ28 if he ever answers my PM's haha. I've heard some things about changing my stock Delco Platnums to TR55's (I think that is what they are called). Anyways any more opinions would be great!

 

Trapping 103-106 for his mods is VERY high. He has an A4, and only has headers, catback, and intake. With a M6 and similar mods, weight and weather, I trapped 102 mph. An A4 will be 1-2 mph lower.

Every car is different however, but 103-106 is expecting A LOT from his car. He should be trapping around 100-102 mph though, in my opinion

 

There might be two or three possibilities....

First, leaks in the headers before the O2 sensors will kill the power. The LT1 is already tuned too rich, and a leak before the O2 sensors will cause the PCM to dump in fuel the engine doesn't need, reducing power even more. Low gas mileage might possibly confirm this problem.

Use your scanner to look at the long term fuel corrections (BLM's) in as many cells as possible. BLM's significantly above 128 (0%) would tend to confirm the header leak problem, or possibly point to misfires, which will also cause it to run excessively rich.

Check for misfires... see comment above regarding the double hit on misfires.... loses power because its missing, loses more power because the misfires cause it to run rich. Can your scanner access the GM OBD-II enhanced parameters, allowing it to read the total misfire count by individual cylinder?

Finally.... as mentioned above, any mechanical rattling from the exhaust can cause knock retard. The LT4 KM is not designed to solve that problem, its for roller rockers. If it does happen to cure it, its pure luck. Again, your scanner will show you if you have any knock retard.

 

Do yourself a solid and get some good valve springs. JMHO.

BTW, I just happen to have some.

 

Just to elaborate a bit: stock springs are not, in my opinion, optimal for any high reving trips down the track. The difference in having a spring that can tolerate high revs can make be the difference between 90+ and 100 and 14s and high 13s. No matter what else might get you the difference, I am a firm believer in a solid valve train for maximum performance. JMHO