The top MAF value probably went over the limit but it should cap out when you save it anyway and not be an issue.Originally Posted by ccline746pk
If you hover over the entry rate it should give you a range of values. Just set it to the highest value and move on.
The TPS for PE should be in the PE tab. It will be a table and should be set at 90% from the factory. There is usually a hot and a cold value.
One other thing you can alwats drop the highest MAF values back under the limit. Its not like you are ever going to get anywhere even close to them.
So is this the "entry rate"? PE.PNG If so this is the table that comes up: EQ Ratio Adder.PNG and it looks like 1.00 is the highest value for it. I set it to that.
And this is what I found under the PE tab for TPS threshold, it only had one chart that showed 90 across the board, no hot/cold. PE Enable TPS.PNG
Last edited by ccline746pk; 08-16-2018 at 07:49 PM.
Must be thinking of my 0411 L31s for the high values amd dual tables. On the enrichment rate max it out atarting at 50% TPS.
So,
I drove it this morning after loading the tune with the recommended changes:
AFR 14.1:1,
Added 2% to MAF and VE Primary and secondary tables
PE Enrichment Rate, 0-40% throttle left alone (.250, .350), 50% and up increased to max (1.00)
PE Delay RPM: 800,
PE Delay Time: 0.0 sec
PE Enable TPS: changed from 90 to 50 across the board
It drove fine, no noticable shudder, but again that only happens under a load usually climbing a hill. I did notice the fuel trims looked good, almost no positive percentage changes. I will post a data log file later today. And at least by Sunday I should be able to load it up and do a hill climb up the interstate nearby.
Chris
Here is the file from this mornings test drive.
Burban after stock tune+14.1 afr, maf_ve-1.02, pe_entryrate, bypass, time delay.hpl
I am actually at work without my laptop close by yet again.
Did you log any knock retard on this run?
Could you feel the difference in how PE mode comes in now?
So, I didnt feel any noticeable difference.
I did log some knock retard events, see screen grab. It didnt shudder but like ive said before it wasnt doing it every time i drove. At some point this weekend I will take it on a longer, uphill test drive.
Burban 8-17-18.PNG
I know have some questions.
When you did the tuneup did you use parts house parts or did you use AC Delco? I only use AC Delco plugs, wires, caps and rotors. Also are you wires routed correctly in the original wire looms? I have seen numerous ognition issues that allow crossfiring and create spark knock. At 11.5:1 commanded air fuel ratio with a rich fuel map you should not be lean at any point.
I also know these Suburbans have a 38 gallon tank. Seeing that you do not drive it much how old is the fuel you are running around on? These ethanol based fuels do not last very long before they fuel starts to seperste and the fuel loses its octane and volatility.
For testing purposes I would run the tank fairly low, put a can of B12 Chemtool in the tank and put about 18 gallons of premium in the tank. Premium uel like Shell or Chevron have added detergents and cleaners in them. If you have a gummy spider all the cleaners will generally help make it operate correctly again.
PE should be noticeable then again I am sure the PCM pulling 4? of timing is creating a noticeable power loss itself.
Ok,
For the replacement parts I never go with the cheapest, I usually get AC Delco when available.
When reinstalling the wires I did go back in the factory wire looms and routing.
The gas is definitely not old! It is driven daily as it is my wife's only vehicle, the family hauler. We have four young kids and she is always going somewhere. Its just that I dont drive it daily, but she does. And for the record this one has a 41 gallon tank. I have the original window sticker and paperwork for this truck, I am the 3rd owner and it was very well kept when I purchased it a couple years ago.
I can run a tank of higher octane through it, it cant hurt.
So, attached is the latest log file. It did start to shudder when going up the incline this morning. I noticed in the log that it went into knock retard multiple times during the 3 minute period when it was shuddering. The time frame is 12:20 to 12:23. I also noticed during this it had high MAP, up in the 90's. Take a look and let me know what you think.
I will upload the log file and a screen shot as soon as I figure out how to delete the 15 previously uploaded file from the upload manager......
Ok, how do I remove the previously uploaded files from the forum upload manager?? It wont let me upload anything else til I do. I looked in the FAQ section, no help.
A curious question... what is your current spark plug gap? Us Gen VI 454 guys use a .045 to .050 gap. My dad's '98 350 is also gapped to .050" to prevent spark knock while towing.
1997 Chevrolet K2500 ECSB, 0411, 454, headers w/ Exhaust, MSD, 28lb injectors "Biggin"
So, I went with the factory recommend setting of .060. I'm going to try resetting them to .045 tonight.....
I did not think of that one. I have not used the OEM platinums on any of mine in years. I use copper AC Delco MR43LTS marine L31 plugs.
I don't have platinums, I've got standard plugs, ac delcos I think. Not sure of the p/n. It's always the simple things that stumps us..... Well, we will see
By chance have you done a compression test on this truck?
If it were me I'd start at .50 and go from there. .045 may be too little gap and roast them prematurely.
I myself went through a set of platinum "100kmi" plugs in 30kmi... But that's because I'm running a hot coil/8mm wires, and MSD. Plus, if you burn any oil they may foul quickly.
1997 Chevrolet K2500 ECSB, 0411, 454, headers w/ Exhaust, MSD, 28lb injectors "Biggin"
4.7,
No, I havent done a compression check. I really dont have any indicators of engine problems save this issue that has popped up recently. When I pull the plugs I can do that easy enough.
Mango,
I will go with .050, sounds good to me. The truck does not burn/use oil but .050 sounds a little less drastic of a change.
Thanks for all the help, will keep everyone posted.
Chris
So, I regapped the plugs to .050 but I havent test driven it yet. When the plugs were out I performed a compression check:
1: 140
2: 127
3: 128
4: 128
5: 130
6: 132
7: 125
8: 135
Looks ok to me, although cyl 1 is a good bit higher than the rest and it is right next to where the knock sensor is.
I have a transmission question. Does the 460LE use vacuum/MAP to determine when it shifts? I noticed that if the truck downshifts the knock/shudder goes away. I was wondering if it is simply a problem of the truck not downshifting soon enough.
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