njmike

This car is new to me (1996 Chevy Camaro Z28 with A4) and I am trying to make up for years of abuse. I am assuming she is stock with the exception of borla cat back exhaust, K&N cold air intake and some suspension components. The previous owner did not know much about it and it has changed hands 4 times in its life.

History:
So far I have done cap and rotor, coil, wires, plugs, EGR solenoid (was stuck open so the car ran horrible), thermostat, cleaned and oiled K&N air filter, replaced vacuum check valve for HVAC controls, cleaned MAF sensor (used MAF cleaner) and other unrelated things. I checked fuel pressure at rail and it held steady during prime (@40) held pressure for a while. I removed the injectors to make sure none were leaking (need to get new o-rings in the am before I slap it together).

The problem:
I keep having weird problems that I can not seem to track down.

1. I am having Knock Retards all over the RPM/MAP range. I compared the tune to other stock tunes and the spark table seemed a little hot so I put the tables to other stock spark tables. My knock retards have been cut in half but I am still getting a lot of them. One of the logs from today started with the car already warm and the knock counts were 2867 and jumped up to 4790 by the time I shut the car off

2. On 2 out of 4 data logs from today I got a handful of cylinder misfires

3. I just started looking at it yesterday but my LTFT for bank 2 was -100%. This is when I changed the tune over and pulled the PCM fuse to dump the memory. LTFTs still seem off because bank 2 has little variation but bank 1 changes rather rapidly.


Currently I am scratching my head a little

I will verify injector spray in the am and fuel pressure during normal conditions but after that does anyone have any suggestions or want to take a peak at the logs?

Thanks in advance to anyone that may have some insight.
Be easy on me because my experience is on more old school carb setups.

njmike

Link to logs from yesterday and today if anyone is willing to take the time to take a look.

Zippyshare.com - DataLog.zip

Injuneer

Knock count is not knock retard. Its a numerical field that appears to increment based on engine operating conditions, not due to a knock signal from the knock sensor. It only seems to cause knock retard if you had an actual knock event from the sensor. Then it will apply knock retard based on engine operating conditions.

What is the data log file type in your zip file? What data logger are you using? When I try to download it, I get a message that my flash player is out of date, and it tries to download an update, which I will not allow from an anonymous source.

njmike

Injuneer - thank you for taking the time out to help. I was hoping you would pop in because I have seen your knowledge spread around on this and other forums.

I am getting knock retards all over the RPM/MAP range some times it is as little as under a degree and sometimes its upwards of 10 degrees. I was just using the knock count as a point of reference.

I am using Autotap as my data logger. I have exported them into csv files than put them in a zip file for simplicity.

That is why I hate those free hosting sites because they have 80 billion download buttons but I do not have an alternate site to host my file. I swear I am not trying to send anyone something suspicious!
Did you click on this download button?

slick1hunting

I was reffered to use google drive or docs as the file share site by someone for simplicity on both ends but I am clueless how it all works but may be worth trying it. Are you running premium gas?


Posted from Camaroz28.com App for Android

njmike

slick1hunting - google docs is such a clutch idea. I don't know why that never occurred to me!

I am running 93 and have been since I took possession of her. Well the first fill up was 89 and ever since then it has been 93. I would have to guess and say she has had at least 4 or 5 tanks of 93 through her at this point. I was thinking carbon deposits can be a possibility because I really don't think the previous owner put anything about regular in it. When the old plugs were removed they did have carbon on them.

njmike

https://drive.google.com/folderview?...TQ&usp=sharing

New link for data logs in my google docs folder

Injuneer

I'll try and take a look at it. Problem is I just had surgery for a torn rotator cuff and I'm on pain killers. Plus its my left arm and I'm left handed.

Pretty sure I clicked on the correct download button. I tried with both Chrome and IE and both times it wanted to download something.

I'll send you a PM with my e-mail address, so you can send the files to me directly.

njmike

Sorry to hear about the surgery man... wish you a speedy recovery!

Email sent. Thanks again!

njmike

Sorry to throw in another question into the mix but I have another one that maybe related.

Wouldn't my exhaust have a lack of back pressure which could lead to other problems such as a burnt valve? The right tailpipe is a straight through and never goes through the muffler. There are cats on the car but who knows if they are complete or gutted and just there for visual inspection.



Curious because this is just not the normal transverse muffler I am use to seeing on an fbody.

shoebox

That Borla exhaust is not going to cause any problems.

Heal up, Fred! LOL, I just had knee surgery yesterday! We would make a great pair of bookends.

njmike

[QUOTE=shoebox;6947261]That Borla exhaust is not going to cause any problems.

Awesome! Thanks for clearing that up.

Injuneer

Hang in there Rob!!

slopokrodrigez

If your getting any cylinder misfires still, you have to address them first and foremost. I highly suggest leak down on all 8 and go from there.

njmike

The misfires are not enough to trigger a cel and they are not constant. I can not identify a pattern because it will show up randomly or some times not at all.

I will have to invest in a leak down tester because I currently do not own one. I would have already compression tested it but my brother lives an hour away and he has my compression tester (I understand a compression test will only tell me there is a problem and not where the problem is).