Lt1 trans am idle issue?
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Lt1 trans am idle issue? I have a 1995 trans am. At idle it shakes pretty bad when cold gets better as it warms up but never goes away completely. Going down the road it feels great. Other details about the car it has ltcc coil on plug system recently installed, AIR system was just recently deleted, and has been tuned with tuner cats to delete all AIR codes and functions and also set fans to come on at 215 and 220. Every thing else is stock. I did check vacuum on intake seems to be around 18 Ish and no vacuum leaKS any where I can find.
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I have the 9495 scan software for it I'll watch it and see what it is doing. Have not used it yet so we will see but I did use the cats programmer to turn it to air speed density mode to see if that did anything also had no effect so I turned it back. Will post tonight with IAC info
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log i attached a long log of it running and the exe needed to watch the log. I did try turning off the fans and letting it get to the 220s and it did smooth out alot. bad gas maybe?DLOG-Save-2016Apr09-194005-2G2FV22P2S2247222.zip
Scan9495.zip
Scan9495.zip
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From: Maricopa, AZ
According to your log you are running pig rich. It's maxing out the LTBLM limits to the minimum side of things (pulling as much fuel as it's allowed to), on top of that the STBLMs are well below 100, like 60-80 range (128 is the target, but STBLMs rarely sit right at 128, they constantly fluctuate around 1280 +/- 10 ish, maybe a bit more, but never constantly more than 15 off once the LTBLM stabilizes), that means it trying to pull a lot more than what the PCM limits long term (LTBLMs).
Did you change anything else with the LTCC conversion? If not, maybe the timing is way off?? The LTCC still uses the Optical Position Sensor, so it must still be installed correctly for everything to work right. If it's clocked off, it will have timing issues and run poorly, if it runs.
It could be a false rich condition, bad O2s maybe? Does it smell rich? Burning your eyes? If you have a cat, it'll mask a lot of it. But, if you are rich, you'll clog up the cat and foul out the plugs causing even more issues later.
Did you change anything else with the LTCC conversion? If not, maybe the timing is way off?? The LTCC still uses the Optical Position Sensor, so it must still be installed correctly for everything to work right. If it's clocked off, it will have timing issues and run poorly, if it runs.
It could be a false rich condition, bad O2s maybe? Does it smell rich? Burning your eyes? If you have a cat, it'll mask a lot of it. But, if you are rich, you'll clog up the cat and foul out the plugs causing even more issues later.
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The only things I changed was adding the ltcc and deleting the air system (pump, hoses, lines fuse, and relay) the fans kicking on at 215 but that was tuned in over a rear ago and still running the same opti from before (never removed it). It does seem to have some oil on the distributor but did before the change also) so not sure if it went bad or not.
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From: Maricopa, AZ
Have you checked spark strength with a spark strength tester? If you still have all the original Opti stuff, you could reinstall the wires, coil, and ICM (bypassing the LTCC) and see if that cures it. If so you know it's something with the LTCC. If not, it's something else.
The only things I changed was adding the ltcc and deleting the air system (pump, hoses, lines fuse, and relay) the fans kicking on at 215 but that was tuned in over a rear ago and still running the same opti from before (never removed it). It does seem to have some oil on the distributor but did before the change also) so not sure if it went bad or not.