Erratic Power Whilst On Boost... Please Help!

[MercuryXr6Turbo]

I just wanted to run by you an issue I'm having with the car. Took the car out last night and when accelerating and coming onto boost the power would surge erratically... to the point that it replicated as if I was coming on an off the throttle but my throttle position was constant at about 3 quarters down. The harder I accelerated the worse it felt and more it surged on and off boost / power. Since the tune a couple of weeks ago I have been noticing it, but not to the degree of last night as I do mostly day driving and don't drive that hard during day traffic. And seems its not as bad during the day. However like most problems it doesn't happen all the time... some days good some days not.

It did happen on my previous tune before injectors, actuator and cat were added, but as it was only running 10psi, I'm guessing it was less noticeable due to this and only happened rarely anyway. When it did it occasionally with my previous tune I thought it my have been the actuator struggling to hold constant boost but with now running the 12psi actuator I thought it would correct it so that's definitely not the issue.

Any experiences or ideas on what it could be would be appreciated as I want to get it running right!

Also Merry Christmas to everyone and all the best for the New Year.

[ratter]

Assumimg it's not miss firing, it sounds like another torque management issue shutting the throttle, but guessing is not acceptable enough to rememdy the problem, it needs to be data logged to see what is going on.

[MercuryXr6Turbo]

Cheers for the quick reply, I see this "torque management" mentioned a bit... don't really understand it though?!? Is this something the tuner can rectify?

A thought I had was coil packs... you think I can rule that out?

Thanks Ratter...

[ratter]

Coil packs or spark plugs will give a consistant miss fire feel but if the throttle is shutting and reopening it will feel like a surge issue.

Your tuner has access to the required parameters to change if this is what is happening.

[MercuryXr6Turbo]

Cheers Ratter, really appreciate your guidance mate. I'll get the car into the tuner after Christmas / New Years.

If anyone else has thoughts or comments also I'm keen to hear then I can have every possibility looked over at one time.

[MercuryXr6Turbo]

Ratter, just thinking further into this... is a Torque Management issue something that the tuner should / would address when tuning therefore avoid me now having a problem? It it an area of the tune he has neglected to check? If so I should be kinda concerned...

Don't worry, not a site sponsor and no finger pointing here.

[XR64LT]

ratter, when my coil packs had sh*t themselves, I was still able to drive the car as normal but it wasnt until it was under hard throttle that you noticed it, I had 5 cracked coil packs too, also spark plugs were not properly gapped either.

mercuryxr6turbo, couldnt happen at a worse time for ya, I would just contact the tuner and just see if he could get it onto the dyno for ya its the only way to find out, after my problem at the drags I rang spiro at autotech straight away and he couldnt get the car on the dyno any quicker than he did.

[ratter]

Miss firing aand surging can be felt as 2 entirely different things, some people can not tell the difference, yes a coil pack or a plug will cause a miss fire but not a surge.

Torque management can do all sorts of things and the main noticeable one is close the throttle, when the throttle is closed the engine receives no boost (as well as no air) so it drops power imediately and then it reopens and gets boost, this can happen constantly and give you the surge feeling.

My wifes car was purchased originally to be my development car, we would make changes on the dyno and all would appear ok, then go out on the road and things may play up a little intermittanly, sometimes we would only get torque management issues in only 3rd or 4th gear although I would not be recommending boosting it in 4th, we tried these things to see what would happen.

Torque management is just not 1 parameter that is turned off when tuning as many think, there can be a series of different things not even listed as torque control that will affect the final torque management control.

Tuners will be like any tradesman, you will get some one who does just enough to get a desired result (final power figure in this case) and others will spend more time to chase drivability and possible problem issues.

[Jman]

I've noticed my car doing this recently.

The thing is with my car... Its soo inconsistant. Sometimes it does it... other times its fine for days.

Will get Danny to check it out

[Isaacxr6t]

I have a similar issue. Did anyone resolve this?