When my car gets to 2100 RPMS (+/- 100 RPMS) the car goes dead for a split second then comes back and bucks real bad. This is starting to be a pain for quick starts off the line...not a launch, just taking off quick. Here is the Log I did. The BOV is stock, it does it with my stock valve and my APS valve.


Log>






Tune>

 

bump

 

That 23.52 AFR seems like an incorrect value as it's the same in all occurrences. How's te IPW and the knock looking? Are you using the NLTS mod?

 

No Knock...Ill look at the IPW. On a second note I just boost leak tested the car it held all the way to 34 psi (on my autometer guage) before the BOV started leaking.

 

You're at 6psi of boost at 2100 RPM?

 

yes, this is nomal

 

Kyle, it still looks to me like the NLTS is kicking in ... like your foot is resting on the pedal. AFR MAP is based on IPW (I think) and would max out if IPW went to 0 (as it does when NLTS is engaged). The RPM jump seems like the same thing that happened to me often when I first installed the NLTS function.

Now, if you don't have NLTS I'm completely wrong.

 

I need to check and see if I have it "on" I have the Tephra patch...its an older version. So I guess it could have some bugs in it. After your post I went for a ride and made sure my foot was off the clutch pedal..its still does it. I also unplugged the + Batt. terminal for 5 min so see if that would help. Its still bucking. Maybe I need to load the updated patch.

 

Logs should show the IPW dropping to 0 in a cell or 2 if I'm correct ...

 

Well I can see the WB go lean (22.4) If I watch it while this bucking is going on. Ill have to get back to my laptop and look at the logs.

 

Have you been playing with the boost limit tables at all? It seems like you are hitting fuel cut, and while it might be something like a bug in the V4 Tephra patch I think its probably elsewhere. Never know until you remove all possibilities though

Couple of things to check on the NLTS-

TPS is a variable- Default is 70% so even if you hadnt changed this it shouldnt have activated
Speed is a variable- Default is 20 km/h this should technically have allowed it to work if the TPS value had been met

 

Im pretty sure I have not messed with the boost tables. Ill check and see. The car will do it in all gears and all speeds. It does feel like fuel. If I have the NLTS off this should not be a factor correct?

 

If NLTS is set to off then it would rule it out as an issue ... correct.

It could be fuel cut, but I have no idea why you'd hit fuel cut at 140 load unless you confused it with the Boost Desired Engine Load table.

 

Ok witch one of you Wizards want to take a quick look at my tune? PM me your Email.

 

My car has done the same thing. It happens to me at partial throttle in second gear at lower RPM when the A/C is running. It bucks quite violantly when it happens. Its happened to me twice and no the computer was not connected when it happened. I have tried to replicate it again to datalog it and have had no luck.