I run sd tune in my 6.0l on hot days my iat sensor reads hot and pulls a ton of fuel. is there a way to tune around this. pulls around 3 points on my afr gauge
I run sd tune in my 6.0l on hot days my iat sensor reads hot and pulls a ton of fuel. is there a way to tune around this. pulls around 3 points on my afr gauge
The IAT won't cause it to pull fuel, there is a spark correction table for the IAT though. Move the IAT sensor if it heat soaks on you as well.
Are you positive you are not losing fuel pressure on super hot days?
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
not really sure if its a fuel pressure issue I guess it could be. timming seems to stay the same hot or cold iat sensor is located toward the end of intake tube
Unless you had the ADD vs IAT table in PE remove fuel, it should not change the AFR.
This is assuming the airflow is correct. If the commanded AFR does not change throughout the run, then you either have an incorrect VE table (speed density) or the fuel pressure is possibly dropping and can't keep the fuel flow up.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
there is a add vs ect in pe but no add vs iat
Some OS's may not have the table then. I was referencing a few P01 calibrations.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
yeah its a p01 system. only place I can find where fuel is affected is in closed loop enable ect vs iat I have the whole table set at 285 degrees.
Are you saying that when the vehicle fully reaching operating temp, or after that, it seems to run lean? too lean after it warms over?
This is very common. Ultimately I suppose I must attribute this to resistance in the electrical systems, and increased volatility/motility of fuel, as everything gets hotter, injectors open slower because voltage is lower that when it was crisp and cold and slightly higher idle speed etc... The heat sucks the air density out of the vicinity and the engine has to huff and puff- heat soaks- to get it's breathing done so it requires more throttle position to maintain the same idle speed- i.e. lower pressure engine idle vacuum. The whole tune shifts slightly as you go from cold and crisp idle vacuum to hot and heat soaked idle vacuum conditions and the area the engine reads from the fuel map is different there. If you pay attention to where the engine "wants to be" when it's heat soaked you can compensate for it there, but then it will be rich when you pass through while everything is cold.
Fuel is also at it's most volatile condition when everything is hot. That means fuel is instantly vaporizing from a valve, and easily escapes during overlap as it completely gaseous without question. You get more overlap-waste, fuel vapors being sucked out when its so hot if injecting before open exhaust valve shuts.
Finally is there another way? Shielding the engines intake tract/intercooling is geared toward increasing air density at WOT but it could also be shielded/ducts to provide an "anti heat soaking" reservoir of cool air. You might also consider water injection, and additional water heat exchangers near trouble engine bay locations such as near the turbine. Many wastegates come with water plumbing in fact and so do some turbo center sections. I mention turbo this and turbo that because they are the most prone to 'heat soaking' as the energy from exhaust is so near the intake's local tract volume, so its a good example of how we handle the worst possible case of heat soaking.
the lean condition has nothing to do with ect its a iat issue
I think what everyone is saying is,Originally Posted by green440
A: hot intake air is less dense, so the engine should get RICHER, not LEANER, without any IAT correction
B: there is no fuel based IAT correction?
I get that it very true. but sitting at a stop light or driving at low speeds it leans its self out to the point of misfiring got to be a way around this
Sounds fuel related still. Like it's losing pressure or boiling the fuel in the rail.
Nothing in the tune is going to cause it to lean out just because the intake air temps sky rocket by 50-80 degrees.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
I got some decent misfires at idle even with 13:1 a/f ratios. It could be your ignition, high heat in the engine bay definitely increases the misfiring for my 20 year old coils. On cold days it never misfires. I can easily fix with venting or maybe even new coils and wires, but I am going to try some water heat exchange first since it runs fine everywhere else and a cam lope will hide all that misfiring anyways once its in.
In any case you can verify with scanner or common sense. The engine shouldn't lean misfire at 15:1 or even 15.8:1 a/f ratio. It should take 16's+ to get an idle lean misfire.
So put a scanner on it and richen the mixture up and see if the misfires clear.
If they do you are going to want to switch to fuel system mode, start with a fuel pressure gauge and compare the fuel pressure when the engine has the issue to when it doesn't, etc...
try setting the cyl charge temp "complex model" switch to disable in ENGINE>AIRFLOW>GENERAL.
also make sure it isn't removing so much timing on IAT that's its in negative numbers.
you need to attach file and some logs mate.
NA 3bar ve changes.hpt
this is the latest tune temps outside are not hot enough to make iat temps pull fuel
Only thing I really noticed was that you left several cells in the OPEN LOOP EQ ratio table at .98, so it can command up to 14.97afr if you hit the right MAP kpa reading. Best to change that to 1.00 and re-calibrated the VE if you did any tuning with your wideband with the way it was previously setup.
Also both timing tables shouldn't be the same. The 3 BAR OS allows you to retain the function of both, so the low octane table should be lower in case the engine sees knock.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
You have an original standard IAT still?
99 TA, Texas Speed LS376, PRC heads, 233/239 cam, Fast 92mm, 95mm TB, card style MAF, Tick TR6060, Strange 4.11 12 bolt axle & clutchpack diff, Strano springs/dampers, Vette 18" wheels, Vette disks, CTS-V calipers, 16lb flywheel, long tube headers, no cats.
the sensor is a gm iat sensor located in the air intake tube toward the air filter end of the tube . the car is a 85 monte carlo I used a k&n air intake from a Silverado pickup so the air intake tube is plastic
unplugging it will generally dump about 20% extra on top of what you're asking for. I've never seen what happens for short circuit but I assume it may pull 20%. when it faults just how hot is the IAT reading?
add a data log to look at.
pump gas and E85 have a surprisingly low boiling point. when the fuel is boiling it will go lean also.
car acted ok today but wasn't very hot out today. but I did notice coming to a stop my commanded afr says 12.2 how do I change this I was thinking eq ratio in open loop but the table is ect vs map and car was up to temp 195. my tune is posted in this thread
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