Been away from all this for a very long time, but here goes. I recently swapped a FTI TH400 and 9.5 in stall in my 2000 camaro. Car always idled pretty good with the M6 and tsp 224r cam with me just doing basic idle and part throttle tuning methods years ago. Doesn't idle good at all with the new 3 speed and stall. Surges, SES light flashes, idles rough, its crap. Give it just a little gas, SES light stops flashing and its smooth. Have my idle set to 825 rpm.

So back to the drawing board in the tune, I started with logging my RAF (HPtuners) then pasted it in my tune, on 34 degree day and just letting the car idle to operating temp, no change. Used the special controls in my scanner to adjust the timing from 18 all the way 28 degrees at idle. Seems to like about 23 to 24 degrees, at least thats where its most stable. But still not a good idle, wants to surge sometimes, SES light starts to flash, just rough.

Decided ok, I'll try adjusted my VE table at idle and part throttle using LTFT's. Got the histogram all setup, and for the most part at idle and part throttle all my fuel trims are negative, less than 5 so not bad, at least at idle. Drove at least 20 minutes and stopping some to allow it to sit in the idle cells. Copied the graph in the scanner, go to my tune, do a paste special - Add to the VE table. Reflash my car thinking it'll even out my fuel trims, reset the LTFT's but it actually is making them more negative second and third logs. I was under the impression that decreasing the VE table values make the trims more positive but its doing the opposite and making them more negative, anywhere between -8 and -11 now. What am I doing wrong, or missing here?

 

Have you went back and checked your wiring? Also do you have any DTC's showing up? Could something have got out of wack with the tune? Blinking SES I would think would be misfire. Haven't done a 400 swap, but looking into it also, so just throwing out where I would start.

Did you do a Crank relearn?

 

Might be oxygen sensors gone bad

 

I don't see a tune file posted nor a mod list so I'm going to just take a wild guess and say your engine is about to explode.

 

Sorry yea I need to update my sig been awhile. Mods:
- TSP 224R cam
- long tubes w/tsp true duals
- SLP lid
- P&P throttle body

Stock heads, stock ls6 intake, bottom end, stock MAF with screen.

The car was originally a 4L60E, I converted it to a T56 a few years ago. Did the cam swap not long after that along with some idle/part throttle tuning. Car has always ran great since. The initial startup after I did the th400 swap the idle completely changed. I realize that I have considerably less weight hooked to the crank now going from a 28lb flywheel, plus pp, to a 32 pound converter. But I didn't expect such a rough idle with a misfire all of the sudden. Anything above idle and its perfectly smooth. O2's appear to be normal on my scanner but maybe one is lazy and I'm just overlooking it. I can post a tune file when I get off work this weekend.

And no codes other than P0300 random misfire which I've deleted for now until I sort this issue out.

 

Here's my tune. Thanks in advance

 

only got a minute to looks at the tune file (literally), but I see the trans is still on 4l60? Also did you do a crank relearn?

 

first thing I would do is switch to a manual tune before going any further

 

- It's an auto tune trying to be a manual, that never works correctly
- Your misfire tables have not been modified correctly for the cam
- Primary and Secondary VE don't "match"
- Why is your injector flow rate modified?

 

The injectors are factory still, I’ve never touched any of the tables. As far as the main and secondary VE I’ll copy and paste. In 2009 I bought a mail order tune for bolt on’s w/stall only...maybe he altered them, but should not have. I’ll look for a stock file and check everything.

As far as the trans tuning, yes the car originally was an 60E auto. I converted to an M6 and deleted the necessary codes, maxed the shift/TC tables, and corrected for the speedo. Is there something else I need to change as far as the trans goes? I’m currently running a TH400 with a manual VB, and using my front wheel speed sensor for the speedo. Checked it with my GPS and it reads accurate.

Like I said earlier I had no issues before the swap and have been driving with the cam for 2 years at least, M6 of course. I’m doin a gear swap now, and replaced both O2 sensors. I’ll do a crank relearn as well once I get everything put back together, and look in HPtuners repository for a stock M6 tune as well.

 

Any updates? You make any progress?