Rough Idle - Accessport etc.

Hey all, I'm new to LGT land but I'm diggin it so far. My last Subie was an 02 WRX MT, then a couple years on an 02 BMW 330xi AT. I picked up an 05 LGT AT sedan a few days ago. It's a little rough around the edges but I want to get it in tip-top shape over the next couple months.

Firstly, it has a pretty rough idle. The motor is a little bouncy and there's the occasional "knocking" sound that can be heard both from the hood and the tailpipe (missfire?). The car still drives well and seems to smooth out under throttle somewhat and it still has good power (seems a little stronger than my 02 WRX and the Bimmer).

I just ordered an OBD scanner so I can see what codes are coming up since the CEL and blinking cruise lights are on. From what I've read on the internets, new plugs (which apparently were just done a few months ago), new injectors, an ECU flash and a throttle body cleaning should smooth things out. Many sites recommend only one of these things, but I figure I might just do them all at the same time.

So, questions are, I'm thinking of getting an Accessport at some time to do some mild engine tuning. Can I also use this tool to reflash the ECU?

Are there other things I should be considering looking at to address the rough idle? (I know, lets see what codes are coming up first). And, is an Accessport worth it with the 5EAT if I'd just like to squeeze a little more power out of the LGT with some light intake/exhaust mods? Thanks for any info and I look forward to sharing anything I learn on here. Cheers!

 

-Luke

Pick up a can of Seafoam engine cleaner and dump it in the gas tank. Ask the guy at the auto parts store.

 

You can unplug the battery cable for a few minutes, that will reset the ECU.

 

Didn't notice where your from, There are a few Tuners on this site that can help you with Cabb AP. Talk with one of them, before you spend your money. I'm meeting my Tuner at 4:15 today so he can load his map into my new Cobb AP as a Base map.

 

The AP can also read codes and clear them. You could have bought your Scanner from Sears instead of ordering it. Or just put that money towards the Cobb AP.

Thanks Max, I'll give the seafoam a try. I'm in Nova Scotia, Canada. The scanner I ordered came from ebay and got pretty good reviews. It was only $60 so it's probably a useful tool to have around. Is the seafoam something that should be done regularily? I know some of those additives are said to dry out gaskets and seals, but I've heard good things about seafoam. Thanks for your input.

Does the rough idle go away after the car has been warmed up?

No, it's pretty consistient regardless of temperature.

FWIW, My Tuner said, with the lastest version of AP, Cobb may have cleaned up some of the idle issues that happen over time to the OEM engines. He said the keep and eye on the idle issue. Mine has stumbled a few times, CEL P0172, and seems like it floods after a re-start. Mine seemed fine driving in today. Mine would have isues when I came to stop sign or pushed in the clutch on the highway too slow for traffic at the off ramp. Car has stalled twice over the last 6 weeks.

 

He hinted there is another Rev to the AP coming out in a few.

 

I wouldn't use seafoam at every fill up, but IMO once a year or so shouldn't hurt.

Update, car had the code again sitting in traffic friday evening. I cleared the code and it ran fine since.

 

Begining to think it's #1 injector ?