Go Back   LS1TECH > CHASSIS, SUSPENSION, APPEARANCE > General Maintenance & Repairs
Sign in using an external account
Register Forgot Password?
Search

General Maintenance & Repairs
Leaks | Squeaks | Clunks | Rattles | Grinds
Sponsored by
Gearstar Performance Transmissions

Welcome to LS1Tech.com!
Welcome to LS1Tech.com.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join LS1Tech.com today!


Reply
 
Thread Tools Search this Thread
Old 08-12-2013, 07:29 PM   #1
Teching In
Garage is empty, add now
 
Trader Rating: 0
Join Date: Sep 2005
Location: New Jersey
Posts: 8
Default 2001 Suburban 1500 4x4 - Hard Starting - injectors?

Been awhile since I posted, though not LS1 or Fbody specific figured the engines are the same and you could help me out. I have a 2001 Suburban 1500 4x4 with about 120,000 miles. For some reason it has a hard time starting, especially after a long trip when it gets up to temp and sits for about an hour or so. It cranks fine and strong but for a second or two after cranking it starts but you can tell it was a rough start (almost feels like their is to much fuel because i feel a sputter). I searched and pretty much every item most people have an issue with that would cause this has been replaced. Let me give you a list:

New parts:
Fuel Pump (Left me at the side of the road, now pressure at the test port is @ 55 PSI and holds steady)
Fuel Pressure Regulator (even though no fuel came from the vacuum line, figure I would replace it for $60)
Fuel filter
Spark Plugs
Wires
PCV Valve
Battery

The last thing people seem to be having an issue with was:

1) Fuel injectors
2) Dirty valve train or lots of carbon build

The truck idles fine when it is started so that leads me to believe the throttle position sensor and MAF are fine.

Modifications I have on the truck are:

Magnaflow exhaust
Magnaflow Y-pipe w/ highflow cats
JET Stage 2 ECU piggy back unit (says I need 91+ octane but have been putting in 89,not sure if this could be the cause, but I did run 91 on a recent towing trip and it did the same thing after we stopped at the hotel)
Volant cold air intake


Anyone have any tips or ideas, I am stumped....
nvetro is offline   Reply With Quote
Old 08-13-2013, 08:38 AM   #2
TECH Enthusiast
Garage is empty, add now
 
lt1pwr1's Avatar
 
Trader Rating: 1
Join Date: Feb 2009
Location: Oakland Township, MI
Posts: 613
Default

Well my first assumption was fuel pressure regulator but you already replaced it.

If you have a scanner, take a look at coolant temp reading. Seen them or the wiring go bad and cause the reading to peg at -40 which will dump fuel into the engine.

Also, might want to read the front O2 sensors and make sure they are switching properly since it acts up when it is warm...

Lastly, try cleaning your throttle body and TB blade. Those get carboned up over time.
__________________
98 Bright Red TA, Auto, Flowmaster Catback, 275K miles and still going strong
lt1pwr1 is offline   Reply With Quote
Old 08-15-2013, 10:24 AM   #3
Launching!
Garage is empty, add now
 
Homeless2bNY's Avatar
 
Trader Rating: 2
Join Date: Jul 2009
Location: Upstate, NY
Posts: 242
Default

for this, i would clean MAF and throttle body well.

then take it to s shop and have them perform a injector service.
they disable the trucks fuel pump and feed it alternate source
thru fuel rain.

i do these often in my shop for GM LS engines with hard start, rough idle, stalling
at low speeds cornering.

other thing it check the trans fluid level, a low level will cause this too.
__________________
2002 Camaro SS with bolt on Long Tubes and Intake.
Nothing special. Just my first clean F-Body.
Lovin it.


Homeless2bNY is offline   Reply With Quote
Old 08-15-2013, 10:24 AM
LS1Tech
Pontiac Firebird




Paid Advertisement
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Hard start after car sits for an hour JMAC71 General Maintenance & Repairs 11 04-30-2014 10:04 PM
LT1 hard starting problem. RogueLT1 LT1-LT4 Modifications 14 10-03-2013 08:31 AM
2001 Suburban w/ blown head gasket...maybe? nvetro Generation III Internal Engine 1 07-13-2013 08:53 AM
98 Trans Am hard starting issues, low fuel pressure please help! BigP Fueling & Injection 6 05-22-2013 01:44 PM
Dies, cranks but no start, then randomly starts. Alien Generation III External Engine 15 04-29-2013 04:19 PM



All times are GMT -5. The time now is 12:27 AM.


Powered by vBulletin® Version 3.8.7 AC1
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Advertising - Terms of Service - Privacy Statement - JOBS
Emails & Contact Details