Speed Density tune......should I do it....?
Speed Density tune......should I do it....? Yes I read the sticky and searched....
My issue is my car keeps frying 02 sensors after my new 390ci engine went in. For some reason they last only a couple months and then I start running so rich I only get 100 miles to a tank of gas during regular street driving.
Should I just go get it SD tuned and toss the 02 sensors.....?
Other option is pretty expensive (about $1,800 total parts and labor) which will mean a new complete wiring harness install and a new 0411 PCM at the same time.....and a quick dyno tune anyway to make sure its right.
SD tune is probably $300-$400.....
.
My issue is my car keeps frying 02 sensors after my new 390ci engine went in. For some reason they last only a couple months and then I start running so rich I only get 100 miles to a tank of gas during regular street driving.
Should I just go get it SD tuned and toss the 02 sensors.....?
Other option is pretty expensive (about $1,800 total parts and labor) which will mean a new complete wiring harness install and a new 0411 PCM at the same time.....and a quick dyno tune anyway to make sure its right.
SD tune is probably $300-$400.....
.
TECH Fanatic
Joined: Sep 2003
Posts: 1,058
Likes: 1
Try it. If you don't like it you can go back or change it. Software can be overwritten.
Note, if the car is driven on the street, I would VE tune it and then see what happens first.
I run a MAF less, no 02 setup and it runs great. I do have my own software though and can touch it up as needed, which is required time to time.
I say give it a try. Its fun to experiment with these toys we own.
Note, if the car is driven on the street, I would VE tune it and then see what happens first.
I run a MAF less, no 02 setup and it runs great. I do have my own software though and can touch it up as needed, which is required time to time.
I say give it a try. Its fun to experiment with these toys we own.
Try it. If you don't like it you can go back or change it. Software can be overwritten.
Note, if the car is driven on the street, I would VE tune it and then see what happens first.
I run a MAF less, no 02 setup and it runs great. I do have my own software though and can touch it up as needed, which is required time to time.
I say give it a try. Its fun to experiment with these toys we own.
Note, if the car is driven on the street, I would VE tune it and then see what happens first.
I run a MAF less, no 02 setup and it runs great. I do have my own software though and can touch it up as needed, which is required time to time.
I say give it a try. Its fun to experiment with these toys we own.
.
Teching In
Joined: Aug 2014
Posts: 44
Likes: 0
From: Toms River, NJ
Are you going to install a Wideband? I love SD and I run a mafless no 02 setup as well going straight SD. But I still have a wideband in the car (I actually have two widebands since I run TD's) to keep an eye. How else will you know if something goes wrong? You pcm won't it gets no feedback after the combustion cycle if you eliminate o2's.
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TECH Fanatic
Joined: Sep 2003
Posts: 1,058
Likes: 1
Seems like the beef is with closed vs open loop, not MAF+SD
vs SD-only. But the sensor problem doesn't have any popular
solutions (mine was to go back to shorties; I'm happy, people
sneer, I don't care).
Anyhow, going to SD-only would not address your trim-drift
problem. Going to full time open loop, perhaps with OL STFT
enabled (you might elect to set all of the idle-range EQ values
to something a bit off from stoich, to inhibit idle trimming which
will remain bent) may be more what you're looking for. If the
MAF is not causing you problems (you have raised none MAF-
related) then it's really not a bad instrument, much more
forgiving of environment, minor mods and state-of-things than
speed density alone can be. As long as you keep it clean.
vs SD-only. But the sensor problem doesn't have any popular
solutions (mine was to go back to shorties; I'm happy, people
sneer, I don't care).
Anyhow, going to SD-only would not address your trim-drift
problem. Going to full time open loop, perhaps with OL STFT
enabled (you might elect to set all of the idle-range EQ values
to something a bit off from stoich, to inhibit idle trimming which
will remain bent) may be more what you're looking for. If the
MAF is not causing you problems (you have raised none MAF-
related) then it's really not a bad instrument, much more
forgiving of environment, minor mods and state-of-things than
speed density alone can be. As long as you keep it clean.
MAF tuning is WAY quicker than a good speed density tune. Tuning the entire VE table, plus temp compensation curves is no way near as quick as tuning a MAF frequency curve. And JimmyBlue hit it, why throw away the maf when the problem isnt related to the MAF. You can run OL MAF all the time too if you wanted.
My 02 sensors never had a problem in 10+ years with these same LTs and my 427ci. I'm suspecting that when my new 390ci was installed last year the wires have been pinched somewhere and they are either melted or getting very hot and causing a problem with the signal in the wires.
We are going to trace everything and see if we can find an issue. I might also just buy a brand new wiring harness re-pinned for an updated 0411 PCM and just install that....get a new tune....then it will be fine.
.
We are going to trace everything and see if we can find an issue. I might also just buy a brand new wiring harness re-pinned for an updated 0411 PCM and just install that....get a new tune....then it will be fine.
.
Seems like the beef is with closed vs open loop, not MAF+SD
vs SD-only. But the sensor problem doesn't have any popular
solutions (mine was to go back to shorties; I'm happy, people
sneer, I don't care).
Anyhow, going to SD-only would not address your trim-drift
problem. Going to full time open loop, perhaps with OL STFT
enabled (you might elect to set all of the idle-range EQ values
to something a bit off from stoich, to inhibit idle trimming which
will remain bent) may be more what you're looking for. If the
MAF is not causing you problems (you have raised none MAF-
related) then it's really not a bad instrument, much more
forgiving of environment, minor mods and state-of-things than
speed density alone can be. As long as you keep it clean.
vs SD-only. But the sensor problem doesn't have any popular
solutions (mine was to go back to shorties; I'm happy, people
sneer, I don't care).
Anyhow, going to SD-only would not address your trim-drift
problem. Going to full time open loop, perhaps with OL STFT
enabled (you might elect to set all of the idle-range EQ values
to something a bit off from stoich, to inhibit idle trimming which
will remain bent) may be more what you're looking for. If the
MAF is not causing you problems (you have raised none MAF-
related) then it's really not a bad instrument, much more
forgiving of environment, minor mods and state-of-things than
speed density alone can be. As long as you keep it clean.
I was just thinking it might be easy just to get a SD tune......but I need the front 02's anyway for that, so I need to find the problem no matter what.
.
Not a good way to continue to get help. It was a very valid question. If there is now a problem with the o2 sensors, there is a good chance the problem could present itself elsewhere too. It's much better to fix the problem than bandaid it.
On The Tree
Joined: Jan 2013
Posts: 191
Likes: 0
From: Newcastle
I run SD CL in my ls1, i drive the car every day and it got good drivability, good fuel milage and makes good power for the mild mods it has, ive tuned a number of cars in SD, the throttle responce is much better than a MAFF tune, iam not a fan of MAFF, but i guess it has its benefits at times, SD all the way for me
If the throttle response if better, then the maf tune was off, I have done both and cannot say one to the other, A member way back stated the same thing that he got better throttle response with a SD tune, When I asked how could he tell, he had some comparisons of something on MAF vs SD and quoted that the SD tune was x milliseconds faster. MILLISECONDS? and he could feel that, wow.