Idle on stand but not in engine bay...
Idle on stand but not in engine bay... This should be a quick one, I'm a newb so please take pity and use small words, the Engine in question is a 4.8 and has a cam, injectors and will have turbo by end of winter. I got it tuned enough to start and idle on a stand a few months ago by using a pressurized injector cleaner which on the video looks to have about 50+psi of fuel pressure. Finally got around to stabbing it into the engine bay with my 4L80E. It starts but dies, I was only running 45#'s of fuel pressure which I'm hoping is the problem.
Any thoughts?
I'd turn up the pressure and check but I just dropped off the drive shaft and don't have a yoke to keep it from leaking which by the way I was filling the tranny without the yoke and it started to hemorrhage after about 7-7.5 quarts. I guess I never filled a tranny before with out the shaft in it, kinda caught me by surprise!
I guess one more question, could there have been drag from the tranny which caused it to stall? Everything I know says that ain't it but I thought I'd ask...
Evidence..
https://photos.app.goo.gl/CGoS1hehVFczMmQZ9
Any thoughts?
I'd turn up the pressure and check but I just dropped off the drive shaft and don't have a yoke to keep it from leaking which by the way I was filling the tranny without the yoke and it started to hemorrhage after about 7-7.5 quarts. I guess I never filled a tranny before with out the shaft in it, kinda caught me by surprise!
I guess one more question, could there have been drag from the tranny which caused it to stall? Everything I know says that ain't it but I thought I'd ask...
Evidence..
https://photos.app.goo.gl/CGoS1hehVFczMmQZ9
Vats were dumped prior to first startup. I increased the fuel pressure to 55# and it started and idled for a little while then died again, it did however sound much better while it was running. Here is the tune/log I had in it when it would idle on the stand. Once I get my drive shaft back I'll see if I can log whats going on and post that up.
I built a return style fuel system with an aeromotive regulator. All I had to do was get a working gauge and crank up the fuel pressure to 55#
https://photos.app.goo.gl/qywAkUtjjED5Gq8A9
now all I need to do is everything else!
https://photos.app.goo.gl/qywAkUtjjED5Gq8A9
now all I need to do is everything else!
Okay so I did a ton of reading, made some inj adjustments based on the Banish's info and my idle still surges. The engine is in the truck but I have not plumbed and exhaust or the cooling system so I only run it for like 45-60 seconds. It's also friggin cold outside. Desired idle is high right now as well until I get a better ball park idle. I'm really just learning all this stuff so I'm sure I'm not logging the right stuff either but I'm hoping for a little help and I willing to learn<br /><br />Here is the log file, what jumps out is the advance to RPM correlation. What I don't know is if the advance is causing the RPM drop or if the RPM is messing with the advance and then what is cause? If someone has a little time and can steer me in the right direction I'd appreciate it.<br /><br />
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I guess I should mention I thought the idle was straightened out but not really. I think the initial fire is good, subsequent (word of the day) fluctuate.... but I can't nail that pattern down.
I'm starting to think I should get the cooling system set up and then get an O2 in it before I go much further.
I'm starting to think I should get the cooling system set up and then get an O2 in it before I go much further.
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Crap, I do have a 2 bar map!!! Thanks for spotting that. i totally forgot to put my orig map back in. I think I'll just change the OS now to a 2 bar map since I will be running a turbo in a few weeks.
this is a P59 PCM, anything I need to be aware of when I flip to a 2 bar OS?
this is a P59 PCM, anything I need to be aware of when I flip to a 2 bar OS?
TECH Regular
Joined: May 2015
Posts: 487
Likes: 4
there are some good youtube tutorials on 2 bar o/s conversion.... when you convert over you will have to manually copy your old VE or adjust as needed
be sure to change the offset and linear for the map sensor recommend settings.... depending on your location the baro should read like 101kpa
be sure to change the offset and linear for the map sensor recommend settings.... depending on your location the baro should read like 101kpa
I had it idling pretty good and then went ahead with the 2 bar conversion. Was pretty confident I was going to start from 0 again but I needed to do it so..
Used the recommended 2 step process of writing the full virgin 2 bar tune then wrote calibration after I made basic VE/MAP changes
For the VE changes, copy/pasted in every 10kpa of orig up to 100, then used my values at 100kpa, added 25% to them and pasted it into the 210 line, interpolated vertical values to get a starting point.
Got the 2 bar settings from Sloppy site and pulled 3.5 out of the offset ( from 9 to 5.5) to get it to 101kpa which is what I needed to see.
https://sites.google.com/site/sloppy...identification
thought it was odd that a 2 bar map has a 207.66 linear kpa but I went ahead and used it....
As I thought.... it won't idle again but at least the work I'm going to do will be with the right 2 bar map. While I was out there I added and subtracted idle air, adding helped a little bit but nothing exciting, I think the idle air values I have are too high based on other similar tunes I have seen. Subtracting from the idle air wouldn't even let it fire for any time at all. Wonder if the MAF calibration values I have are too high? I'm thinking about reverting the spark and MAF values to the stock values and see how far it gets me.
Oh and another weird thing, a bunch of channels are greyed out and not capturing values on the logger, even stuff like injector flow rate? Can't even add them back, whats up with that?
Added the latest tune/log if someone cares to take a look. And thanks again for catching the 2 bar map miss on my part, feeling kinda stupid..
Used the recommended 2 step process of writing the full virgin 2 bar tune then wrote calibration after I made basic VE/MAP changes
For the VE changes, copy/pasted in every 10kpa of orig up to 100, then used my values at 100kpa, added 25% to them and pasted it into the 210 line, interpolated vertical values to get a starting point.
Got the 2 bar settings from Sloppy site and pulled 3.5 out of the offset ( from 9 to 5.5) to get it to 101kpa which is what I needed to see.
https://sites.google.com/site/sloppy...identification
thought it was odd that a 2 bar map has a 207.66 linear kpa but I went ahead and used it....
As I thought.... it won't idle again but at least the work I'm going to do will be with the right 2 bar map. While I was out there I added and subtracted idle air, adding helped a little bit but nothing exciting, I think the idle air values I have are too high based on other similar tunes I have seen. Subtracting from the idle air wouldn't even let it fire for any time at all. Wonder if the MAF calibration values I have are too high? I'm thinking about reverting the spark and MAF values to the stock values and see how far it gets me.
Oh and another weird thing, a bunch of channels are greyed out and not capturing values on the logger, even stuff like injector flow rate? Can't even add them back, whats up with that?
Added the latest tune/log if someone cares to take a look. And thanks again for catching the 2 bar map miss on my part, feeling kinda stupid..
Went back to stock idle air, spark and maf, no dice. Fires and dies.
Added 10% to maf calibration since I have no airbox or filter, no better
Added 10% to Idle air no better
Then I did a weird thing,
unplugged MAF, little better, still **** but a small improvement
unplugged IAC, little better again would actually stay running but not good
Exhaust smells rich for each attempt
Can the VE tables be the problem? They are stock interpolated to 2 bar from 0 to 100 KPA
The included tune is using the injector info from the stickie above, same thing happens with the Banish inj info.
What about the MAP linear and offset? I took those from sloppy and tweeked the offset till I saw the right baro at key on.
Added 10% to maf calibration since I have no airbox or filter, no better
Added 10% to Idle air no better
Then I did a weird thing,
unplugged MAF, little better, still **** but a small improvement
unplugged IAC, little better again would actually stay running but not good
Exhaust smells rich for each attempt
Can the VE tables be the problem? They are stock interpolated to 2 bar from 0 to 100 KPA
The included tune is using the injector info from the stickie above, same thing happens with the Banish inj info.
What about the MAP linear and offset? I took those from sloppy and tweeked the offset till I saw the right baro at key on.
Back to idling!
From Stock I went with
- Banish Injector data for SD 80's
- MAP linear and offset to 200/8.33
- MAF Calibration copied from Sloppy colorado build
- VE , Multiplied the 400 800 and 1200 columns by .6, .8, and .9
Fired right up.
Then pulled 10% from Idle Air to see if it got better, nothing to note
Tune and the log enclosed.
Hope Santa brings hot side for turbo so I can add the O2's and a WB.
From Stock I went with
- Banish Injector data for SD 80's
- MAP linear and offset to 200/8.33
- MAF Calibration copied from Sloppy colorado build
- VE , Multiplied the 400 800 and 1200 columns by .6, .8, and .9
Fired right up.
Then pulled 10% from Idle Air to see if it got better, nothing to note
Tune and the log enclosed.
Hope Santa brings hot side for turbo so I can add the O2's and a WB.