2003 LSV8 surges @ 4k to 4250

[Dudeinthething]

I never noticed this before with the original air intake, but when I put a K&N 57 Series Aircharger Intake Kit on, the car at full throtle will surge twice between 4000 and 4250 rpms. Would the cause be to much air and not enough fuel or does the computer need to be reflashed for the increase air supply? Also, sometimes at normal driving it will do the same @ 3k to 3250 rpms. One person suggested it is the Mass air sensor not being able to handle the increase airflow.
Any suggestions would be very helpful.

Thanks
John

[shorod]

Welcome to the forum!

Does it feel like a misfire? Have you ever checked your spark plugs for the dreaded oil filling the spark plug wells which is common on the 2000-early 2002 models?

-Rod

[Dudeinthething]

Have not checked the plugs, need to. If it is misfiring, would in it do it all the time in the RPM band? Could it be the MAS? I know that the engine spec has max torque also at 4K. Could it be in the tranny.

[shorod]

A misfire would not necessarily occur all the time. It will depend on the engine load at the time, etc.

It would certainly be worth your time to carefully clean the Mass Air Flow (MAF) sensor. I've seen oiled air filters contaminate the MAF before and cause certain driveability issues, but that would take some time to show up. Plus, this usually occurs if the filter is over-oiled following a cleaning. The way a K&N comes from the factory would not be likely to cause MAF contamination. A K&N will not flow enough extra air to cause a problem with the engine or MAF.

I doubt that it would be a transmission issue. Certainly, if it were a transmission issue, it would be just be a coincidence that it showed up following a K&N install.

-Rod

[Dudeinthething]

What should I look for when I take out the plugs? Also, I read a earlier thread about being able to lite up the rear tires from a stand still. I cannot. Is this due to the electronics throttel control? I turn off the traction control, still nothing. Accelerations is great, but with 280HP, I would assume that I could get some tire spin.
Thanks for all the info so far.

John

[shorod]

When you pull the coils off the spark plugs, check the coil boots for signs of oil wetting. If you see wetting, then you may have valve cover gaskets that are leaking. However, I see from you title that you have a 2003. The leaky valve cover gaskets were supposedly fixed halfway through the 2002 model year, so the possibility of leaking valve cover gaskets is pretty low.

My 2004 LS V8 wouldn't spin the rear tires from a dry stop either. I think this is due to the electronic throttle control. Like yours, the car was plenty fast, but it didn't seem to dump power to the rear wheels from a standing start. My wife's 2002 LS V6 seems to have more punch from a stop, but my 2004 would catch up to it quickly.

-Rod

[Dudeinthething]

I do apperiate the advice. I will check it tomorrow and let you know. I love these cars, they are so under rated.
Have you ever heard of anyone reprograming their computer or putting a chip in to gain some HP?

John

[shorod]

The only "chip" I've really heard of for the LS is the SCT Calibrator. It's available from Fast Parts Network (http://www.trademotion.com/partlocat...cfm?siteid=318) and possibly other places. I believe there are a couple of folks who participate on this forum that have the SCT.

-Rod

[Dudeinthething]

No Oil found in the coils or on the plugs. I guess the next stop will be the dealer.

[Drag214]

When you say "surge", do you mean the RPMs jump up or is there a sputter (engine shacking)? If your RPMs are jumping up but your still going the same speed, You may need to look toward your transmission for the problem and solution. The RPMs jump up because the transmission is shifting to a lower gear. It may be be caused by low oils levels. If your oil levels are low or if you don't have the additive added to your oil, according to the technical servce bulitian that was put out for this transmission (5R555N), this problem may become irreversable. Thats the problem I had with my transmission. It might be time to get your transmission service. It cost me 170.00 ! I didn't have the tools to do it myself.