[iflo]

There is this annoying rattle I keep hearing under hard acceleration only. I bet it's just a loose nut/bolt on heat shield or exhaust bracket but I just want to make sure its nothing to do with my engine.

Please note this rattle is present with and without a tune.

Here is my Procede logs. 1st, 2nd and 3rd gear pulls. I was turning/merging while in 1st gear by the way. Any input would be great.

[Tzu]

only ON hard acceleration or coming off? I'm willing to bet its wastegate rattle. Log wastegate DC.

Those boost spikes on shift worry me. Do you have stock DV's?

[iflo]

Originally Posted by Tzu

only ON hard acceleration or coming off? I'm willing to bet its wastegate rattle. Log wastegate DC.

Those boost spikes on shift worry me. Do you have stock DV's?

It's not WG Rattle, as this is ONLY during hard acceleration not during deceleration.

Yes stock DV.

What do you guys think about IC? -4 at one point in 3rd??? Sorry if I am a noob at reading these things.

I have to get under the car and have someone rev it to see if something rattles near the pipes.

If it only happens under load, do you think this is engine related? Or maybe engine mount issues?

[shiv@vishnu]

guys... guys... come on now. If you don't know how to interpret a datalog, please don't try to give anyone advice. Those shift spikes are normal. Every car with any tune (even stock) will have them. And ignition correction is NOT the same thing as ignition advance. Ignition correction is just the correction that the Procede applies. There isn't much useful data provided in the logs. But what is provided looks normal.

If you have a rattle under acceleration (with and without the tune), you will need to jack up the car and look for anything unusual. Most likely an exhaust part hitting a cross brace when the engine torques over. Either way, you'll need to give it a thorough inspection.

[iflo]

Originally Posted by shiv@vishnu

guys... guys... come one now. If you don't know how to interpret a datalog, please don't try to give anyone advice. Those shift spikes are normal. Every car with any tune (even stock) will have them. And ignition correction is NOT the same thing as ignition advance. Ignition correction is just the correction that the Procede applies. There isn't much useful data provided in the logs. But what is provided looks normal.

If you have a rattle under acceleration (with and without the tune), you will need to jack up the car and look for anything unusual. Most likely an exhaust part hitting a cross brace when the engine torques over. Either way, you'll need to give it a thorough inspection.

Thanks Shiv....and yes like I suspected, it's most likely something loose under the car or engine bay. I'll make my girlfriend stick her head out and try to locate it

[Tzu]

I'd like to make it clear that I was in no way implying that the tune is causing those spikes and I am happily running 6-14 with perfect timing. Pre-throttle body MAP sensor is picking up the increase in charge pipe pressure once the throttle plate slams shut, initiating the DV's to do their job. elementary FI.

I was asking for myself. I recently purchased AWE bov/dv's, and they hiccup at high rpms, giving me similar spikes. They hesitate for a second and then release causing rpms to shoot up as excess boost leaks past the plate. Anyway, thats for another thread.