What makes you think they are stock injectors. Just because a random website says they are doesn’t mean much. They don’t cross reference on rockauto to anything. And off throttle running is where bad injector data will show up.
What makes you think they are stock injectors. Just because a random website says they are doesn’t mean much. They don’t cross reference on rockauto to anything. And off throttle running is where bad injector data will show up.
The injector data checks out. Here's what I've come up with next. Throttle cracker settings were probably the reason for it dying coming to a stop. Watch IAC in the last log during that period.
The injector data checks against what?
'99-'00 Silverado.
Did I just not dig deep enough to find the injector part number as a legitimate known matching number. Everything I saw was eBay, Amazon or equivalent.
OK, I'll walk you through it.
My first check is always Rockauto, because it's quick.
https://www.rockauto.com/en/partsear...rtnum=25323974
No matches! Not a big deal, they are often lax with all the superseded numbers if they're more than a few years old.
So...
https://www.google.com/search?q=2532...lter=0&start=0
which leads to
https://www.injectorplanet.com/produ...otors-25323974
which, while semi-shady, what with all the Amazon Affiliate links and whatnot, gives some interchange numbers:
17113582
FJ10063
Back to RA:
https://www.rockauto.com/en/partsear...rtnum=17113582
Look up the applications, go to one of those in the catalog...
https://www.rockauto.com/en/catalog/...+injector,6224
Then pull a stock file for one of those vehicles and open it in Compare, and none of the fields for the injector data are highlighted in green.
(and yes, for anybody else reading this, this is the kind of work people have to put in when you show up with just an outdated part number or other unknown parts. you're welcome.)
I went through the same process, I just didn't trust Injector Planet cross reference enough to assume that it means much. It may be good, but if the tune doesn't fall in place pretty quick, I would expect the injectors are a problem. Not mention the actual source is likely to be Amazon or eBay and counterfeits of suspicious injectors.
It fell into place after only 2 revisions to VE. OP stated he kept the factory injectors when he did the swap. Wanted to make sure nobody changed them out previously. The only thing I don't like is the dip at 400-800rpm mid-MAP. So, I lowered Min Fuel Mg to correspond with Min Pulse to see if that helps.
That's how I do it, too. Injector Planet is great for cross-referencing. Was kinda hoping you had some super secret GM tech way of finding P/N info.Originally Posted by blindsquirrel
If I'm looking at it correctly the IAC goes to 0 and then comes back up as it tries to save it?
Loaded the new tune and I'll log on the way home from work.
Thanks again for all the help man!
Here is the latest log. I'm having the same issue as when I tried to mess with the throttle cracker and follower before. It doesn't die when coming to a stop but the idle hangs for a while. If I bring the idle down by not pressing the clutch it will come down faster.
The VE table is looking awesome though I think.
2003 Silverado 5.3 VE log 11.hpl
Alright I've made a few changes to address what you described. See what it does for you.
Ok definitely a lot better. The idle hangs maybe 1-2 seconds when its warmed up. When its cold Id say maybe 5 or so seconds.
In the beginning and end of the log is more coming to a stop.
What tables are you modifying?
2003 Silverado 5.3 VE log 12.hpl
Throttle follower and main spark. Press Ctrl+L with the tune open to see the changelog. Or open SD_6 then press Ctrl+1 to open SD_5 as a comparison. Changes will be highlighted green.
Look through the tables. See if things improve.
Finally gave up and bumped warm idle up 50rpm. Doesn't seem to matter what IAC was doing at idle with respect to stability, so I want to increase air demand to maintain control. 850rpm seemed controllable.
Last edited by SiriusC1024; 02-15-2024 at 07:52 AM.
I totally forgot I could do that haha thanks. Do you think I should move on to calibrate MAF?
I also have another issue where the truck won't start every time. Sometimes I'll just crank and crank sometimes pop. But if I let off the key and try to start again right away it starts every time. I'm not convinced it's in the tune. I was thinking it may be the cam or crank sensor or related wiring since this truck was swapped from a v6? Maybe it is in the tune but I don't know.
What vehicle did the throttle body come from?
I think this should run full time SD. I recommend the SD OS.
Being a swap, and your intermittent starting failure, did you do a crank relearn?
I can only assume the throttle body came from the 2000 yukon. It's DBC and appears to be stock. I didn't do the swap so I'm not sure if they did a crank relearn but that does make sense. I'll do that today.
I was wanting to run it in SD because I have a tbss intake for it that I want to put on and I want to boost it eventually. Which OS should I run? Speed density enhanced, 1 bar 2 bar? If I can set it up now to boost it later and still be able to keep it running well I will do that.
Last edited by Fastmike91; 02-15-2024 at 02:42 PM.
1 bar OS since you have a 1 bar MAP sensor. If you want 2 bar from 1 bar you'll have to write entire your current tune then go to 2 bar. Save your tune somewhere safe.
Pull the throttle body and do a thorough cleaning. Remove the IAC and clean the passages.
It's also possible that you have a vacuum leak. STIT is bringing BRAF much lower than I'd expect.
When you decide to put on the TBSS intake be sure to change out the knock sensors and harness while you're at it. Don't forget to RTV the gasket plugs, buy new steam tube gaskets, and get new intake manifold gaskets.
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