My CEL still works with my AEM EMS but its only works for codes like the brake system, SRS, etc not actual engine codes. However, the engine codes that the car throws are mostly emissions related anyway so who cares

 

didn't know this.. cool

 

Error code PO171 System to Lean (Bank 1)

Cleared it... does this pose a threat? Tuning it on the 22nd

 

That means your AFR in closed loop is not able to reach 14.7 under some condition. Did you pull the freeze frame data for the DTC? The Freeze Frame will tell you under what conditions the DTC ocurred.

Do you have a wideband AFR gauge? In closed loop your AFR should be right around 14.7. Under boost (should be open loop at this point) your AFR should be in 11-12 range.

This could be very bad - stay outa boost and see if it happens again during gentle driving.

 

What is closed loop? What is open Loop?

I cleared it, and it hasnt come back yet... keeping it under 3krpm... drove around for about 20minutes...

 

lean is bad...thats when things blow up. I suggest you don't got into boost till you get your tune.

 

those other ports are taken up by your oil lines.

 

understood.

no boost until tune... /cry

Thats what i was thinking when I read it... it said lean... I held my breath!... ugh...

 

Closed loop is where the ECM is monitoring the AFR and attempting to hold around 14.7 for better fuel and emissions. Most of the time you are driving the car will be in closed loop. Open loop is where the ECM runs off a preset map to maintain a safe AFR during acceleration or certain load conditions. My ECM typically goes into closed loop at about -4 inHg on the MAP sensor or under different throttle or speed conditions. The ECM open loop map is also influenced by the long term fuel trims that are learned during all of the closed loop driving.

 

ah, ok. that makes more sence to me... thanks.

i'm still going to keep it out of boost... i'm going to stay under 3k rpm until the 22nd when I get her tuned...



Another question... when I get it tuned, can I stick my testpipe back on? its a 60mm and I have stock exhaust...