Go Back   Blazer Forum - Chevy Blazer Forums > Mechanical & Maintenance > General Tech Help > 2nd Gen S-series (1995-2005) Tech
Sign in using an external account
Register Forgot Password?
Search


Welcome to Blazer Forum!
Welcome to Blazer Forum,

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 start new topics, reply to conversations, privately message other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join Blazer Forum today!


Closed Thread
 
 
 
 
LinkBack Thread Tools Search this Thread
  #1  
Old 02-26-2012, 05:54 PM
New Member
 
Join Date: Jul 2011
Posts: 6
linegtdt52 is on a distinguished road
Default 1996 s10 blazer hesitation / bucking / surging

I have a 1996 4door s10 blazer 4x4. I love this truck but i've been an idiot and started throwing parts at it and have not been sucessful. I only seem to see the issue in closed loop (full operating temp) under a load like goin g up a hill. It is prevelant in D and overdrive so I know its not the torque converter. I can visibly see the rpm gauge bounce up and down 500 rpms. When I put it down to full thorttle, the problem goes away until U get back to a hill and light acceleration like 1800-2k rpms. Oh yeah, No check engine light either as well as soft codes. So far I have changed out :

Spark Plugs
Wires
Ignition Coil
Distributor Cap
Button
Coolant Temperature Sensor
Idle Air control Valve
Throttle Positioning Sensor
Mass Air Flow Meter
Fuel Pump / Sending unit
Fuel Filter
Cleaned O2 Sensors
spider injection system

I checked the spark plugs and all seem to be in generally good shape . good compression. Please help I am lost. I think I am just gonna get a MAP sensor and put it in to say I have done EVERYTHING shy of replacing to computer. Thanks again for taking a look.

Last edited by linegtdt52; 02-26-2012 at 08:20 PM.
  #2  
Old 02-26-2012, 06:11 PM
Chevy33's Avatar
Junior Member
1998 Chevrolet Blazer
My Garage
 
Join Date: May 2010
Posts: 364
Chevy33 is on a distinguished road
Default Bucking?

Is the truck shaking and chattering like it doesn't want to go with the rpm increasing?
  #3  
Old 02-26-2012, 06:25 PM
Captain Hook's Avatar
Moderator
1998 Chevrolet Blazer
My Garage
 
Join Date: Mar 2009
Location: Belleville, Michigan
Posts: 5,681
Captain Hook has a spectacular aura aboutCaptain Hook has a spectacular aura aboutCaptain Hook has a spectacular aura about
Default

I realize you've replaced a ton of stuff with no success, including the fuel pump. Now it's time to do some diagnostics to find out what the problem really IS. One thing to keep in mind is just because a part is new, doesn't necessarily mean it's good. You may have already replaced the right part, but without diagnostics you'd never know.

Have you checked fuel pressure and leakdown? Key ON, engine OFF, fuel pump running: Pressure must be 60psi to 66psi and must remain above 55psi for 10 minutes after the pump shuts off. Fuel pressure is not monitored by the OBD system and because it's not monitored, it can not set a DTC and turn on the SES light. If there's a problem with a sensor, or its circuits, it will set a DTC.

What brand of parts did you use? Some aftermarket stuff, putting it gently, is junk right out of the box.
__________________
You have to know how it works,
to figure out why it doesn't.
  #4  
Old 02-26-2012, 08:22 PM
New Member
 
Join Date: Jul 2011
Posts: 6
linegtdt52 is on a distinguished road
Default

fuel pressure is perfect. timing is perfect.
  #5  
Old 02-26-2012, 08:40 PM
Captain Hook's Avatar
Moderator
1998 Chevrolet Blazer
My Garage
 
Join Date: Mar 2009
Location: Belleville, Michigan
Posts: 5,681
Captain Hook has a spectacular aura aboutCaptain Hook has a spectacular aura aboutCaptain Hook has a spectacular aura about
Default

Define "perfect"
__________________
You have to know how it works,
to figure out why it doesn't.
  #6  
Old 02-26-2012, 09:02 PM
New Member
 
Join Date: Jul 2011
Posts: 6
linegtdt52 is on a distinguished road
Default

fuel pressure pressured and held @ 64. fuels seems perfect to the rail. it only surges when its warm.
  #7  
Old 02-26-2012, 09:03 PM
New Member
 
Join Date: Jul 2011
Posts: 6
linegtdt52 is on a distinguished road
Default

vacuum is at 17 psi constant @ idle
  #8  
Old 02-26-2012, 09:19 PM
Captain Hook's Avatar
Moderator
1998 Chevrolet Blazer
My Garage
 
Join Date: Mar 2009
Location: Belleville, Michigan
Posts: 5,681
Captain Hook has a spectacular aura aboutCaptain Hook has a spectacular aura aboutCaptain Hook has a spectacular aura about
Default

Have you checked camshaft retard? If so, what was the reading?
Do you have a scan tool capable of viewing streaming data?
__________________
You have to know how it works,
to figure out why it doesn't.

Last edited by Captain Hook; 02-26-2012 at 09:28 PM.
  #9  
Old 02-26-2012, 09:52 PM
Starting Member
 
Join Date: May 2011
Posts: 187
chevyblazer9588 is on a distinguished road
Default

My 1995 Chevrolet S10 Blazer LT 4 doors do the same things. I will try to take a video of it tomorrow if I can get somebody to come with to video tape it for me while I am driving.
  #10  
Old 02-26-2012, 10:08 PM
Captain Hook's Avatar
Moderator
1998 Chevrolet Blazer
My Garage
 
Join Date: Mar 2009
Location: Belleville, Michigan
Posts: 5,681
Captain Hook has a spectacular aura aboutCaptain Hook has a spectacular aura aboutCaptain Hook has a spectacular aura about
Default

1995 uses a different computer control system, (CMFI with OBDI or OBD1.5) but it's worth a try
__________________
You have to know how it works,
to figure out why it doesn't.
Old 02-26-2012, 10:08 PM
 
 
 
Closed Thread

Tags
1995, 1996, 2000, 95, acceleration, blazer, chevy, closed, hesitation, idle, loop, s10, surges, surging, transmission, upgrade, warm


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 On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
92 s10 blazer extremely bucking jerjohn77 Engine & Transmission 3 02-13-2011 08:05 PM
Hesitation and ruff idle on my 1996 chevy blazer dkratt 2nd Gen S-series (1995-2005) Tech 1 07-09-2010 04:22 PM
hesitation/hiccup/bucking @ 2k rpm.. ideas? corvette535 Engine & Transmission 30 03-10-2009 05:46 PM
hesitation/hiccup/bucking rusignuolo Engine & Transmission 1 02-19-2009 06:49 AM
1996 Chevy Blazer-Hesitation problem juliuss 2nd Gen S-series (1995-2005) Tech 11 02-22-2007 10:51 AM

Advertising

Featured Sponsors
Vendor Directory
Our Sponsors

All times are GMT -5. The time now is 09:20 AM.

Internet Brands, Inc.