I'm trying to help out a friend. This started as a simple idle fix, and has grown into something else entirely.
ECU - P59 from a 2007 Express with originally equipped 4L80 (shouldn't need segment swap right?)
Engine - 5.3L
Cam - 228/228
Converter - Yanks 3600
Drive by Cable due to vehicle -- 89 S10 Blazer
Tune info - SD, MAF fail at 1Hz, closed loop tune
So, the idle was all over the place, which he was thinking was due to the intake. In a day, via email, we were able to get the truck to start and idle quite nicely. Then, shifting into gear, airflow demand goes up greatly - from 9 to 15 g/sec. So, we dropped idle spark in P/N to use more air and not need the IAC to react so fast, hoping this would help it recover. In order to keep the idle from falling off, we had to greatly increase the RPM low proportional and decrease the rpm high proportional. Anyway, he is now able to start the truck, and it idles good and smooth, although the spark line is saw-toothed. 12 degree idle spark in PN and 18 degrees in Drive - with 31 in the 400 and 0 columns to try to support it when it wants to die.
So, in order to get into gear, We have to hold the pedal and let it settle down from there. Then, after going for a drive, shifting into gear is very harsh. Every time we load a fresh tune, it goes back to dying when going into gear. In the log, when the shift happens:
00:01:04.811 - TCC slip is -140.8 rpm and 257%
00:01:04.821 - TCC slip is 570.3 rpm and 76.3%
Then, RPM starts falling fast, and the IAC opens really fast to compensate
00:01:05.151 -- TCC slip is 487 rpm and 0.0%
00:01:05.891 -- full stall
When it has learned its initial going into gear from using the throttle to get it to go in, the subsequent shifts into drive chirp the tires - even with the brakes applied. It's almost like the TCC is going into full on lock in gear and idle.
We have tried minimum TCC everywhere from 10 to 90. I've seen a million threads on "My TCC won't lock" but I can't find anything about the TCC acting like it's fully locked going into gear. Anyone mind taking a look to see what I'm missing?
ozzie - jacob tune18 TCC values -ve.hpt
8 - 24 5th.hpl
8 - 24 4th.hpl
Friend's comment after log 8-24 4th: "hey , I drove around the block like 10 times it felt good , going into reverse was a pain I had to force it bad.. after the drive it goes into drive from park like a rock .. it chirps the tires and same in reverse but after the tires chirp in reverse it dies."
Log 8-24 5th is a simple start and let it idle for a minute then put into gear with no additional throttle
Edit - I should add we were able to get it to reliably go into gear without throttle, but only by running it 13:1 AFR
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