How can I fix my lean warm up cycle w/ osiris??
When I turn my car on ( hot or cold ) it runs very lean ( 17:1-18:1 ) and sometimes even misfires for about 30 seconds and then the O2 sensor goes into closed loop and everything is fine. My fuel trims are within +/-10% at all times and my car idles beautifully and runs smoothly with the A/F always bouncing around between 14.5-15.0. Heck, even my cold/hot startups are great...it's the O2 open loop process that is screwy.
I played with the startup enrichment on osiris but it apparently only makes the initial starting process rich but then it goes lean again.
Am I missing something?
I played with the startup enrichment on osiris but it apparently only makes the initial starting process rich but then it goes lean again.
Am I missing something?
I may be wrong as I do not tune but doesn't osiris have different modes you can set on the fly with your cruise control?
can't you just set it to stock (so it doesn't misfire/etc) until its warm and then set it to your preferential setting?
can't you just set it to stock (so it doesn't misfire/etc) until its warm and then set it to your preferential setting?
The issue is probably due to his modifications, not the tune itself. It's probably that the osiris program doesn't have access to the table he needs to adjust, or that there is another way of doing it that he hasn't discovered yet. I haven't used the osiris software yet personally, so I can't be much more help.
Sounds like you just need to add some fuel in the idle area in the compensation table. Also, +/- 10% is actually a pretty big swing, I like to keep them within 3%, and always on the rich side. It should never be ADDING fuel.
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Now I'm anxious, I truly believe this could be the problem. I try it out tomorrow. Thanks!
Last edited by GT-ER; Aug 3, 2010 at 08:49 PM.
You could also try adding a bit to the value in the MAF Comp table at the voltage level corresponding to the engine at cold/fast idle. Changing K multiplier will change your fuel settings for the entire operating range of the engine as it will change what BFS the ECU hits.
You could also look at increasing injector latency. Since the latency (dead time) value is added to pulsewidth, at low pulsewidths, such as idle, it will have quite an effect (because it is a higher % of total PW) on AFR that tapers to nothing noticable at higher injector pulsewidths.
If your car tends to run lean and have a positive trim at idle, but hits the proper AFR and has a 0 or negative fuel trim at cruise, adjust injector latency to decrease the split between the fuel trims at idle and cruise. If the fuel trims are even, but positive, adjust the MAF comp table in the appropriate voltage cells and leave latency alone.
You could also look at increasing injector latency. Since the latency (dead time) value is added to pulsewidth, at low pulsewidths, such as idle, it will have quite an effect (because it is a higher % of total PW) on AFR that tapers to nothing noticable at higher injector pulsewidths.
If your car tends to run lean and have a positive trim at idle, but hits the proper AFR and has a 0 or negative fuel trim at cruise, adjust injector latency to decrease the split between the fuel trims at idle and cruise. If the fuel trims are even, but positive, adjust the MAF comp table in the appropriate voltage cells and leave latency alone.
Last edited by BlinkerFluid; Aug 3, 2010 at 09:07 PM.
I sort of remember vince telling me that +/- 10 is fine. Most of my comp tables have been adding fuel though so maybe that could be it. I'll try to play with the K multiplier and subtract fuel with the comp tables to see if that helps. It kinda makes sense since I believe the comp tables aren't used during warmup. I could be wrong though, I just know that during the warmup, playing in RTT will not do anything to the fueling until it goes into closed loop.
Now I'm anxious, I truly believe this could be the problem. I try it out tomorrow. Thanks!
Now I'm anxious, I truly believe this could be the problem. I try it out tomorrow. Thanks!
You have to massage the MAF table and injector scaling values to fix this because you don't have access to the startup map.
I had the EXACT same issue after I scaled my injectors with the PMAS MAF map. Ended up putting injector scaling back to stock and messing with the trims instead.
I had the EXACT same issue after I scaled my injectors with the PMAS MAF map. Ended up putting injector scaling back to stock and messing with the trims instead.
I got lucky... the 440cc's are close enough to stock that I haven't had any issues with the stock injector latencies aside from messing with the K a little bit. As long as I don't mess with the latencies, cold and warm starts are spot on.
UPDATE: I confirmed with DW that the latencies are the same for the 440's and 600's... so perhaps you could try putting your latencies back to stock and adjusting your K to compensate?
Last edited by djamps; Aug 5, 2010 at 04:31 PM.
There are definitely many more maps and tables that can be dug out. Especially controlling the cooling fans, maps based on warm-up, etc...


