How to richen A/F on cold startup???
05-04-2011, 08:30 PM
#22
What I mean by root problem is, that you say your fuel trims are ok in cl and the wideband seems to agree that they are correct. Although for whatever reason with a proper open loop target table, your wideband reports lean.
Somewhere in that chain of events is either a cal issue or some of the data is bull crap.
A thought that comes to mind is that many times on cold start the alternator runs pretty hard and keeps the voltage up. Once the car is warm and the fans are going etc it will tend to run at a lower voltage. Perhaps there is some issue with the injector offset vs voltage? Which will change your ol readings with a good cal everywhere else. There are several tables related to open loop operation though. Your narrow bands seem to agree with the wideband which is kind of alarming, and you say the car runs poorly in open loop. Another trick is to let the key sit on so the narrow bands heat up before starting the engine so they will have a better chance of being accurate and useful as a form of comparison for open loop measurement.
Might want to try bouncing this issue off of your tuner. He is a really competent guy when it comes to these engines, I've seen several examples of his work and its always right on with how I do things.
Somewhere in that chain of events is either a cal issue or some of the data is bull crap.
A thought that comes to mind is that many times on cold start the alternator runs pretty hard and keeps the voltage up. Once the car is warm and the fans are going etc it will tend to run at a lower voltage. Perhaps there is some issue with the injector offset vs voltage? Which will change your ol readings with a good cal everywhere else. There are several tables related to open loop operation though. Your narrow bands seem to agree with the wideband which is kind of alarming, and you say the car runs poorly in open loop. Another trick is to let the key sit on so the narrow bands heat up before starting the engine so they will have a better chance of being accurate and useful as a form of comparison for open loop measurement.
Might want to try bouncing this issue off of your tuner. He is a really competent guy when it comes to these engines, I've seen several examples of his work and its always right on with how I do things.
05-04-2011, 08:36 PM
#23
Thanks for the reply. It does not run poorly in OL, it just could run a bit smoother. I might be fretting over nothing here as well.
After driving the car with the table lowered two points this morning, it was running bad likely as a result of running too fat. I then went back to the normal tune and lowered the table by .5 and I will test it in the morning.
I am going to take it to Bluecat in the fall for a tune up and concentrate a bit more on non WOT conditions. I believe it is dialed in on WOT and yes he really knows these engine inside out and has a great reputation.
After driving the car with the table lowered two points this morning, it was running bad likely as a result of running too fat. I then went back to the normal tune and lowered the table by .5 and I will test it in the morning.
I am going to take it to Bluecat in the fall for a tune up and concentrate a bit more on non WOT conditions. I believe it is dialed in on WOT and yes he really knows these engine inside out and has a great reputation.
