I've got a problem with my car dropping the power out for a split second at 2800, 3200 and 4100 rpm. The problem started once I got my car tuned via dimsport.

Originally it started out as minor... barely there. Then it got progressivly worse until it finally threw a cyl 3 misfire. Took it to the dealership and they determined it was the cyl 3 plug wire. problem went a way and started coming back recently.

I recently changed the oem coil pack out for a new oem coil pack and oem wires. I cleaned the map sensor with carb cleaner and it's still there.

I am certain this isn't the yo-yo effect... but rather a split second drop out where the car just loses power.

Any one have any ideas what this could be?

 

When checking the plug wires, did they/you check the actual plugs?

If the new tune leaned it out any, this can cause a mis-fire type situation (ie. harder to ignite).

I had a cyl #2 plug electrode erode away. It idled fine and would drive "decent", but would spit and sputter under boost. Sometimes in the same RPM range. And the EML light would come on.
Changed the plugs and everything was peachy again. BTW the plugs were Denso's with 25k miles.

 

good thought i'm running the 7 series jcw plugs with about 15k miles. cheap to change plugs so ill give it a shot.

 

I second the plug check. I just replaced my #3 and #4 plugs because the electrodes were gone. Car would idle fine, run fine, but under loat at high rpm's would hesitate bad. Changed plugs and we are back on the road again. The plugs that went bad were denso ik22's, replaced with NGK Iridium one step colder gapped at .044

 

I thought they thought it was your belt slipping? I was there when you had it tuned by Jan at the begining of May...

 

ummm. I've got a new belt on the car and it hasn't seemed to help. it could be tensioner I guess. the thing in may was actually a re-tune cause I added jcw injectors. that was a weird day... we hit the belt with contact cement and it got better but didn't go away. my question about the belt is if it's the belt setup I can't figure out why it would happen at the samerpm constantly.as for plugs im running oem style plugs that are one step colder then stock... I've tried putting the original plugs in just to try it and it doesn't help the issue.thanks for the help guys.

 

How about restoring the factory tune and seeing if the problem goes away...

 

So, any resolution on this?
Did you revert back to a factory tune and have the issue go away?
Did you swap old injectors back and have it issue go away?

Inquiring minds want to know...