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Discussion Starter #1
ok, i did alot of work to my truck that i havent driven in a month and a half. pacesetter lts, ory, 4l80e, and a re-tune from nelson performance for all of that and delete rear O2 sensors, and EGR. i charged up the battery so it had a good amount of juice to it since it was dead. the truck turns over fine and starts but it will jump to 500-1500rpm then it will just die. i tried tapping the gas lightly and still it wouldnt idle. i just dont know where to start.
 

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ok, i did alot of work to my truck that i havent driven in a month and a half. pacesetter lts, ory, 4l80e, and a re-tune from nelson performance for all of that and delete rear O2 sensors, and EGR. i charged up the battery so it had a good amount of juice to it since it was dead. the truck turns over fine and starts but it will jump to 500-1500rpm then it will just die. i tried tapping the gas lightly and still it wouldnt idle. i just dont know where to start.
And you haven't run it since you received the new PCM from Nelson? Sounds like you may need to perform a security relearn. Try to start it, once it fires and dies, keep the key in the run position for 11-12 minutes (until security light shuts off). Then, turn the key off for 30-45 seconds. After, attempt to start again. Repeat process three times. On the fourth time, it should fire right up.

Hopefully that's the problem...

Justin
 

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Discussion Starter #5
no it wont idle even with gassing it. i have 2 service engine codes. P1336 which is crank sensor relearn(happens when you get a new pcm no big deal for the motor to run), and P0405 which is EGR circut low voltage or something like that. but i had nelson performance delete my EGR and i have the block-off plate installed on my passenger side header. is there something else i was supposed to do to delete EGR? i think theres something you have to do on the motor but im not sure. but i kind of think thats not it either because EGR only works at cruising speed not WOT or idle...:think:. also technically i have 4 SES codes but there is 2 P1336, and 2 P0405???:banghead:.
 

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Discussion Starter #6
ok, my truck didnt have EGR from the factory so why would it be throwing a code for the sensor?!?
 

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i bought new 02 sensors and still nothing...its setting off EGR codes still. even though i dont have EGR is there anything i need to unhook? also if i didnt have EGR before the re-tune then i got it tuned for EGR delete would that make it do what its doing and not idle at all?
 

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i have no idea still the truck fires up strong and jumps up to 500-1500rpm and then goes right back down. i checked my fuel pressure and its good, somebody told me it might be the "GEM module" because that controls the security system. and when that malfunctions even on a factory truck it thinks the vehicle is getting stolen and it starts the vehicle then dies instantly...anybody know where this GEM module is located?
 

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Discussion Starter #10
ok, i got a little mixed up the "GEM module" i was talking about that somebody told me it is, is the BCM. I found that my BCM fuse in the underhood fuse box was blown its a 10A so i replaced it and still nothing. a buddy told me it needed to be re-set so he told me to disconnect the battery for 15-20 mins so i left it unhooked for 30...still nothing after connecting the terminals back on. i then re-checked the fuse, its still good. im now thinking its either my tune that has something wrong with it...or my security/passlock system is having a problem. because when it thinks the vehicle is being stolen it will start fine then die extremely quick which its doing. the manual said to set the alarm off then turn it off with the keyless entry and then start the vehicle within 15 seconds and still nothing with that either...anybody got ideas? i even rented a handheld scanner from autozone and it only throws one code now P1336 which is crank sensor relearn whick always happens until a re-flash. but on the scanner if i go to "I/M MONITORS" it says all the systems are ready such as fuel pressure, spark, etc. except 02 sensors it says "NOT READY". but it doesnt throw any time of 02 sensor code. and they are both BRAND new:nono:i have no idea:think:.
 

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it's not fast enough
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mine did that when i have a bad mass air flow sensor.
went through 4 of them in 2 months.

unplug that if you can't figure it out
 

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Discussion Starter #12
mine did that when i have a bad mass air flow sensor.
went through 4 of them in 2 months.

unplug that if you can't figure it out
already tried it bro, i unplugged it and tried to start to see if it was the same, better, or worse. and with it in atleast it will fire up for a second but it didnt start at all...well barely. so im assuming its good because the truck starts better with it in if it was bad it would probly be the same...
 

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well, i finally got it. it was the security relearn that needed to be done...but i tried soo many different things trying to start my truck that i fouled my plugs a little bit. pretty sure they are the originals from 93,587 miles ago...but i went and replaced all 8 plugs and wires and it ran like new...
 

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Discussion Starter #15
Definitely had those symptoms. Glad you got it figured out. :shake:
thanks for the help justin. i figured out what i did wrong. i kept trying to get it started then decided to do the re-learn. but i didnt wait 10 mins to do the re-learn after attempting to start more than 3 times. the system goes into lockdown for 10 mins after 3 unsuccessful attempts to be started by an unrecognized sorce to start. i then disconnected the battery for 30 mins, then went right to the re-learn...and on the 4th attempt like you said it fired right up and stayed running. thanks again:shake:.
 

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so is your truck all fixed and running now? if so, how do you like the 80e?

EDIT: Nick told me all you need is your rear driveshaft and that you're getting that tomorrow.

wanna race? :evil:
 

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TUNED BY ME!
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Hey glad to see the truck running. So what do you think of the 80? I like it except for the fact i need a supercharger now, boltons aren't enough to push that beast off the line. I don't know if i told you or not, but i lost like .3 on my 1/8 just from the tranny and stall, that 80 takes so long to rev in 1st. You'll love it on the freeway though, my truck will downshift to 2nd at like 82 mph, it's awesome.
 
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