GMT 800 & Older GM General Discussion 2006 & Older Trucks | General Discussion

Truck wont start *NEW VIDEO ADDED*

Thread Tools
 
Search this Thread
 
Old Aug 30, 2010 | 09:14 PM
  #1  
1slow01Z71's Avatar
Thread Starter
Tin Foil Hat Wearin' Fool
iTrader: (36)
 
Joined: Oct 2004
Posts: 23,204
Likes: 4
From: Austin, TX
Default Truck wont start *NEW VIDEO ADDED*

Got everything done and tried to start it, but it just wont fire off.

Ive got fuel pressure(58 at the rail)
Checked all grounds
Pulled the shrader valve and purged 2 gallons of gas out til it smelled good, it had 2-3 gallons of old gas and 5 gallons of new 93, I tried to start it before purging and when it didnt start I added an additional 5 gallons of 93 and purged it some more.
My dad said the test light flashed when I I was trying to start it(stuck in a plug wire) so Im pretty sure Ive got spark. Ill confirm tomorrow with an old spark plug
It would turn over and as it turned over more and more it sounded like it would almost catch and want to start. Even a couple times it puffed some smoke out the tailpipe.

I didnt have my laptop with me to scan the computer to check if there was anything going on.

It used to have a 420 an 80e now its back to an LQ4 and 60e. Nelson is doing the tuning. Im going to try swapping a totally stock PCM in and see if that does anything. Ive never had to do a case relearn or whatever the hell its called when you install a new PCM. Ive always tossed in the computer and it worked fine but Ive read of a few people having problems. Ill look up the procedure for that I guess.

I didnt have a lot of time to mess with it a lot tonight but I took off early tomorrow so I can have more time to mess with it. Anybody think of anything I might be missing?

Video added to post 24

Last edited by 1slow01Z71; Aug 31, 2010 at 04:17 PM.
Reply
Old Aug 30, 2010 | 09:17 PM
  #2  
dlt76028's Avatar
12 Second Truck Club
15 Year Member
iTrader: (13)
 
Joined: Sep 2007
Posts: 5,883
Likes: 2
From: Crowley, TX
Default

I would look more into the pcm or security relearn maybe?
Reply
Old Aug 30, 2010 | 09:23 PM
  #3  
Quik's Avatar
5 year bitches!
iTrader: (7)
 
Joined: Oct 2003
Posts: 4,890
Likes: 2
From: Pittsburgh!!!!!!!! Pa
Default

curious...is this a stock motor or does it have parts in it? ive ran across this before and it was lack of compression from intake valves staying open
Reply
Old Aug 30, 2010 | 09:27 PM
  #4  
1slow01Z71's Avatar
Thread Starter
Tin Foil Hat Wearin' Fool
iTrader: (36)
 
Joined: Oct 2004
Posts: 23,204
Likes: 4
From: Austin, TX
Default

gt2-3, 7.4 pushrods, patriot duals

Im not sure what type of lifters are in there, they were just some xtras I had laying around from another build. Even if they were LS7 lifters my rods would be a little short so the valve thing wouldnt be a problem.

03 LQ4, gt2-3 cam, volant intake, built trans with tb converter, corsa catback is the full mod list right now.

After I confirm Ive got spark, if I do Im thinking computer issue of some sort. It should idle off a stock 5.3 tune? I knwo I wont be able get on it with a 5.3 tune but Id settle for getting it started right now.
Reply
Old Aug 30, 2010 | 09:34 PM
  #5  
dlt76028's Avatar
12 Second Truck Club
15 Year Member
iTrader: (13)
 
Joined: Sep 2007
Posts: 5,883
Likes: 2
From: Crowley, TX
Default

Mine would almost start like your describing, and it was the security relearn.
Reply
Old Aug 30, 2010 | 09:37 PM
  #6  
1slow01Z71's Avatar
Thread Starter
Tin Foil Hat Wearin' Fool
iTrader: (36)
 
Joined: Oct 2004
Posts: 23,204
Likes: 4
From: Austin, TX
Default

Wouldnt happen to have a link to the security relearn? Nelson used to have it on his site but I dont see it anymore.
Reply
Old Aug 30, 2010 | 09:37 PM
  #7  
Quik's Avatar
5 year bitches!
iTrader: (7)
 
Joined: Oct 2003
Posts: 4,890
Likes: 2
From: Pittsburgh!!!!!!!! Pa
Default

im assuming stock rockers and you cant mess those up. the file would have to be totally jacked up for it to not fire. a stock file will fire it but not run well at all. check to see if you have good compression, cause you can have good spark and fuel but not fire cause its no compression. A stang recently did this and the rockers were to tight [adjustables], i also had this issues years ago and it was bent intake valves.

are you getting fuel to the plugs? pull a plug see if plug is wet
try some ethyer [sp] see if that hellps
do you have 58psi at rail? but ethyer will determine this. spray enough in there to see if it fires. if it fires you have a fuel issue
Reply
Old Aug 30, 2010 | 09:38 PM
  #8  
Quik's Avatar
5 year bitches!
iTrader: (7)
 
Joined: Oct 2003
Posts: 4,890
Likes: 2
From: Pittsburgh!!!!!!!! Pa
Default

security would run for a second then quit, since its based off rpm
Reply
Old Aug 30, 2010 | 09:45 PM
  #9  
1slow01Z71's Avatar
Thread Starter
Tin Foil Hat Wearin' Fool
iTrader: (36)
 
Joined: Oct 2004
Posts: 23,204
Likes: 4
From: Austin, TX
Default

The 58psi is at the gauge on the shrader valve. Didnt pull a plug but I will tomorrow.

I know its atleast got a pretty good seal per cylinder since I had my air compressor hooked up to the cylinders with 150psi of air. Shouldnt have bent valves due to the tame setup Ive got.
Reply
Old Aug 30, 2010 | 09:47 PM
  #10  
dlt76028's Avatar
12 Second Truck Club
15 Year Member
iTrader: (13)
 
Joined: Sep 2007
Posts: 5,883
Likes: 2
From: Crowley, TX
Default

Originally Posted by 1slow01Z71
Wouldnt happen to have a link to the security relearn? Nelson used to have it on his site but I dont see it anymore.
http://www.nelsonperformance.com/passkey.htm
Reply



All times are GMT -5. The time now is 03:25 AM.