Notices
Tuning, Diagnostics, Electronics, and Wiring HP Tuners | EFILive | Hand Held Programmers | Stand Alone PCM's | Electronics | Wiring Diagrams

5.3L with 4l8e: Long crank time

Thread Tools
 
Search this Thread
 
Old 05-25-2024, 08:39 AM
  #1  
Teching In
Thread Starter
 
Spencer11's Avatar
 
Join Date: Dec 2023
Posts: 7
Likes: 0
Received 3 Likes on 2 Posts
Default 5.3L with 4l8e: Long crank time

Hey guys, I have been having a long crank time since I swapped this engine in. About 6-8 seconds to crank after driving it around however the first start of the day is always instant.

Not sure what could be causing this as it runs great, only thing I can think of is that the fuel pump is going out as it is at 340k miles.

Just shoot some ideas,

thanks
Old 05-25-2024, 08:47 AM
  #2  
TECH Fanatic
iTrader: (1)
 
wretched73's Avatar
 
Join Date: Jul 2010
Posts: 1,136
Received 350 Likes on 269 Posts
Default

Sounds like the fuel pressure is leaking down while it sits. No leaks? Check valve could have worn out
The following users liked this post:
strutaeng (05-25-2024)
Old 05-25-2024, 08:49 AM
  #3  
Teching In
Thread Starter
 
Spencer11's Avatar
 
Join Date: Dec 2023
Posts: 7
Likes: 0
Received 3 Likes on 2 Posts
Default

Originally Posted by wretched73
Sounds like the fuel pressure is leaking down while it sits. No leaks? Check valve could have worn out
Didn’t think of the check valve, I’ll check for leaks today when I get a chance.

Old 05-25-2024, 10:00 AM
  #4  
TECH Senior Member
iTrader: (2)
 
FFDP's Avatar
 
Join Date: May 2014
Location: Rogers, MN
Posts: 5,204
Received 552 Likes on 477 Posts
Default

If you cycle the key a few times, will it start right away or does it still do a long crank. That test would help it build fuel pressure.

Other things could be tune related if the engine isn't stock. If it not running a MAF and the tune isn't right.
The following users liked this post:
strutaeng (05-25-2024)
Old 05-25-2024, 10:10 AM
  #5  
TECH Resident
 
strutaeng's Avatar
 
Join Date: Oct 2020
Location: DFW
Posts: 872
Received 191 Likes on 155 Posts
Default

Buy the $30 fuel pressure gauge from HF.

Check for fuel pressure. Possibly leaking injector after you shut it off, or simply just low fuel pressure.
Old 05-29-2024, 07:45 PM
  #6  
Teching In
Thread Starter
 
Spencer11's Avatar
 
Join Date: Dec 2023
Posts: 7
Likes: 0
Received 3 Likes on 2 Posts
Default Solved

After some looking, I found the fuel pressure regulator to be faulty. There was fuel in the vacuum line, easy enough to fix and cheap part. Starts perfect now.

Thanks for everyone’s input. 👌
The following 2 users liked this post by Spencer11:
Jeff71 (05-30-2024), wretched73 (05-29-2024)
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
SSpeeDEMONSS
GMT 800 & Older GM General Discussion
6
10-03-2015 08:21 PM
m3srt
GM Engine & Exhaust Performance
1
08-15-2008 10:41 PM
M. Red WS6
GM Engine & Exhaust Performance
1
07-29-2008 11:02 PM
blacksierraSS
Tuning, Diagnostics, Electronics, and Wiring
1
10-25-2007 10:29 AM



Quick Reply: 5.3L with 4l8e: Long crank time



All times are GMT -5. The time now is 01:44 AM.