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Running pig rich and stalls when warm



I finally got time to do a log and I'll be damned, she fired up. Albeit it took a few times with it backfiring and stalling but then it stayed running. But I don't think I got that corner next to the thermostat housing sealed as when it was running I sprayed carb cleaner it stumbled. So I pressurized the intake and sprayed soapy water there and I couldn't get no bubbles? I don't know how it could be leaking as I put a good 1/4" bead of silicone around the whole intake, mabey I should put a few more layers all the way to the rotors.
 


so i have a lean fuel trim with stalling at stop lights replaced pcv valve maf and has new intake gaskets with plugs and wires fuel pump is at 35kpa at idle have not done any test under a load but i dont think thats the problem going to check vac lines soon but ideas would help missfires on 4&5 randomly service engine soon light will come and go
 


I believe I have all leaks sealed. It seems to be holding pressure for quite a few seconds with all plugged and forcing air into the throttle body. But I seem to still have the same problems with onwards of -22 ltft. I wonder if it could be something with my tune? I couldn't bypass the vats on the 02 regal tune that came with the motor so I uploaded what I believe is a stock 00 Grand Prix gtp tune and was able to use that. Any idears?
 
Well I tried my hand at copying the regal tune over the gtp tune the best I could. I used the compare file and copy/pasted any differences but there were a few that were questionable as they went half green, half pink where as a proper copy goes all pink. I loaded it and it fired up but scanning it showed before 30 secs it went rich at around -17 fuel trims so I guess the tune didn't work. On a side note I have a 3" abs pipe from the throttlebody to an open cone filter in the side of the body for cold air. Could this be too small and not let enough air in for the amount of commanded fuel cause it to run rich? I can't remember if I have done a scan with an open throttlebody or not to see if the numbers are the same or not.
 
I tried disconnecting some sensors today while logging and it changed nothing. First the maf, it stumbled and almost stalled so I had to hold the throttle till it revived itself but was still running rich. Then the map and then the iat both had no effect on the engine and still logged rich fuel trims.
Edit: forgot about the O2 sensor. It had no change as well.
 
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I replaced the fuel pressure regulator and the only thing that changed is my wallet is now lighter. It's still running rich, now -20 for ltft. It's also stumbling and running like crap but I did have the battery dissconnected the past two weeks while I was gone so hopefully it just needs to relearn.
 


I bucked up and got my tune to my tuner and after a few tunes and logs back and forth, he got er settled down. Turns out I needed to reset the fuel trims when ever adjustments are made. I noticed over the past couple days that after driving, when I would start it up again it would sometimes surge or it would start then die right away. And sometimes I would have to give it gas to keep it going. The first start up in the morninhg is no problem it seems when it gets warm it acts up. I it took a few times to get it going then I had to press the gas and it was really stumbling an rich again as i seen the black exhaust out the pipes in the mirror. It barely wanted to stay running but it eventually did with a bit of throttling. Once it gets going then it's normal till I shut it off and start it up again. And ideas as to what would have changed so drastically to cause this total 180? Keep in mind I have not touched anything.
 
The fuel trims were not completely learned while tuning. Some times you need to drive the car for a few cycles or up to a week. Or it's possible that you have a vac leak.
 
I was just looking at my logs and the ait's stood out. When it's starting like crap, the ait's are 40-60 degreese Celsius. It's not that hot touching the intake air tube going down to the cone filter. Do hight ait's default the computer to make it run rich? It starts and runs fine when cold.
 
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