I finally started getting into tuning higher rpms yesterday when all of a sudden the car bucked pretty violently. I was not in boost, just slowing increasing the revs in 2nd gear under vacuum. I repeated this again and within 100 rpm it did it again...between 6200 and 6300 rpm. The log showed that the AFR was fine and the knock was fine. I triple checked my ignition tables and everything looks fine in there as well...at this point I have no clue what is causing this.

Also, while i'm posting, I still cannot get my cold start idle to function quite right. I played a lot with the water temp correction, it helped a bit, but it seemed like I was having to change the number quite drastically to get it help. The hot idle is perfect btw.

 

rev limit set to 6300?

 

set at 8500

 

Could be your coil pack harness needs to be replaced.

Dale

 

Was your air pump turned off when making your AFR tests?

 

airpump, all emission, a/c, and ps are removed....only thing turned on on pfc is idle control

 

The one issue with this is that it worked flawlessly before I went single turbo 4 months ago. I don't see how it would all of a sudden go bad like that.

 

It is a Mazda isn't it? Below is an exanmple.

My ISC worked perfectly: when stock, non-seq with 550/1200 injectors, and
single turbo with 550/1200 injectors.

When I changed the injectors with single turbo to 550/1600 injectors which required removing the ACV, I also removed the fuel fumes purge solenoid.
After that my ISC only controlled idle for electric load. Not for normal idle or A/C.

 

Very true...I'm going to play with it some more tomorrow after I get my alignment. Do some logs..if I still can't figure it out I will post a screen shot of the logs.

 

I’ve seen something similar multiple times on cars I have tuned; in almost every case it has been the spark plug wires. Replace them first before you tear everything else apart.

Dan

 

Really? These spark plug wires are brand new...could they be factory defects?

 

Yes, put your old ones back on that were working before to test.

 

I would if they didn't get destroyed (bought the car and found out later that two were corroded to the leading coil pack)...which is the reason I replaced them in the first place. I guess I need to make damn sure it isn't in the tuning first before I replace my already new wires with another new set of wires.

 

I have a new idea....it could be really bad hesitiation when my 1680's kick in. I just read an old thread where Chuck said he logged the secondary injectors not coming on until 48% inj duty, instead 40% like programmed into the ecu. I assumed that since I was already logging over 45%, the secondaries weren't causing hesitation....which I found to be really odd since I didn't change the settings for the larger secondaries at all other than specifying the new size. Now the better question is, could the hesitation be so bad that it would stop the rev's complete?

I really need to get out and tune for a bit today as I planned, but of course it is raining.

 

Go relog the event with advanced functions and AUX for WB. It will tell you much.

Have you set up your injectors as described in my notes?

 

So did this hesitation start after adding some new 1680 secondary's because if it did and you haven't adjusted your secondary transition (ms) and injector overlap on settings screen #5 then for sure when you get up in the rpm range and your secondary's start to come on your staging will be off causing bucking and some big hesitation. When tuning some pri/sec transitions you can push through it in the rpm range and it will clear up, this is a clear indication of secondary staging issues.
I've also seen this problem when I had some bad wiring going to the secondary's from the wiring harness.
The stock wiring harness for the engine and the coil packs is a big piece of crap check it out very closely.