S300 Running rich after driving for a while

[shane J]

tried differnt ECU when the problem cam around again, car still running poopy. Seems latley if I really gun it a few times it trys hard to clean its self up on the AFR guage. then out of no were the car starting running good again. This is new cause it usally just runs like shit till I start the car up the next morning.
Going to try new harness next.

[crucian]

tried differnt ECU when the problem cam around again, car still running poopy. Seems latley if I really gun it a few times it trys hard to clean its self up on the AFR guage. then out of no were the car starting running good again. This is new cause it usally just runs like shit till I start the car up the next morning.
Going to try new harness next.

I just looked at your tune. It really needs to be cleaned up. You will never get the car to run right without a good low end tune. You can change ECU's and change harnesses all day; the bottom line is, that the car is not low end tuned properly. Cut out the closed loop nonsense and run the car open loop with a good tune. Once you get a good open loop street tune then you can focus on closed loop.

[shane J]

ok but why did it run fine for such a long time then? I have tried messing with the scale's in that area and it doesnt seem to help much. Like I really have to pull a lot of fuel out of the map.

Why does it only happen after driving the car hard for a bit? Unless somthing is really messed up and the cumputer is trying to learn whats going on and it can't..

I will try this today and see if it will respond better.

Im a race car guy not much of electrical wizard, Mechanicaly I build motors and do all the work on my car but this is one area I need to work on. :(

Thanks for the input.

[crucian]

ok but why did it run fine for such a long time then? I have tried messing with the scale's in that area and it doesnt seem to help much. Like I really have to pull a lot of fuel out of the map.

Why does it only happen after driving the car hard for a bit? Unless somthing is really messed up and the cumputer is trying to learn whats going on and it can't..

I will try this today and see if it will respond better.

Im a race car guy not much of electrical wizard, Mechanicaly I build motors and do all the work on my car but this is one area I need to work on. :(

Thanks for the input.

Shane, you have to tune the car in open loop. All the numbers in each column should ramp up as the RPMs go up until your cam runs out of breath, then the numbers will decline; that's around 7000-8000 on the low cam. But on the tune that you posted first, the numbers go up and down in each column. When I tune, I can always tell when the car is running in closed loop when my AFRs start acting wacky.

Don't feel bad about not knowing the electrical part of it. Here at work, I manage 79 mechanics and only about 3 actually know the electrical part of their job. Even up to the supervisors I have running the floor have little clue about troubleshooting electrical and electronic components. lol...

[shane J]

ok but why did it run fine for such a long time then? I have tried messing with the scale's in that area and it doesnt seem to help much. Like I really have to pull a lot of fuel out of the map.

Why does it only happen after driving the car hard for a bit? Unless somthing is really messed up and the cumputer is trying to learn whats going on and it can't..

I will try this today and see if it will respond better.

Im a race car guy not much of electrical wizard, Mechanicaly I build motors and do all the work on my car but this is one area I need to work on. :(

Thanks for the input.

Shane, you have to tune the car in open loop. All the numbers in each column should ramp up as the RPMs go up until your cam runs out of breath, then the numbers will decline; that's around 7000-8000 on the low cam. But on the tune that you posted first, the numbers go up and down in each column. When I tune, I can always tell when the car is running in closed loop when my AFRs start acting wacky.

Don't feel bad about not knowing the electrical part of it. Here at work, I manage 79 mechanics and only about 3 actually know the electrical part of their job. Even up to the supervisors I have running the floor have little clue about troubleshooting electrical and electronic components. lol...

I ran the car in open loop, did a couple full on blast down the high way and the problem cam up within seconds, I then pulled fuel out of the area were it was rich 10.99 in those tables and leaned the mixture out. with in a few minutes the car started to run very lean of course. I then re uploaded the orginal tune and everything ran fine again. Did this again and again twice. Maybe im missing somthing but all the problems are at lowish RPM and at idle.

Im stuck 4 hours away from Vancouver Canada, we have no tuners in are city and im almost ready to think I may have to get my car looked at. I still dont understand why my car used to run fine and not now. I have been running on chipped ecu's for at least 6 years on my older JRSC set ups and S300 mid last year to this year. I have never had a tune change so much on me.

Its almost like a injector is staying open but the duty cycle is fine, and the injectors got cleaned and looked over in the winter. Could my o2 sensor be getting to hot? its brand new maybe 1000 km on it...

If my tune is messed up in those area's could you be able to adjust it for me and I can try it out to see if it works...

[crucian]

After reading through your post again, I'm thinking that you don't have a wide-band o2 sensor. Can you list your entire setup again in detail this time please. For example, injector type and size, ignition system, wideband or narrow band o2 sensor, etc.

[shane J]

Im runing a AEM wide band

Brand new o2 sensor,

ignition is stock, NGK wires, plugs are just run of the mill NGK plugs 2 step colder
Injectors are RC 440

I went out on lunch and the problem happend again, I was just pissed so I pulled a bunch 6% fuel out of the whole table from col 5 down to 5 RPM it worked, Then I started the car up after work and that whol erea was so lean I was scared to drive it like 16.5 or leaner. So again back to square 1.

[shane J]

I will do my best to tune it, but maybe you can help to explain why this has happend, why would it work fine for such a long time and then not work so well. One thing that i did not in my datalogs is I notice the ignition timing drops alot.

When recording the ignition at idle is around 2-5 btc? and the injectors are reading pretty high when they are at this low rpm. If you look at the datalogs I have mention the area were the problem starts, almost 3.0 ms seems high for idle?

[crucian]

Whenever you post your new datalog, post the tune with it. For some reason I can't open the last datalog you posted.

[shane J]

The datalog was the same as the first one I posted on page one. I just tried to make a note were the problem started. take a look a this map and see if its any better. I didnt adjust much, beat on the car tonight and no problems? I did change the map sensor for shits and giggles but had no problems at all. Did seem to run a bit better.

Here is the current tune but cleaned up a little as you suggested