Go Back   Great Lakes 4x4. The largest offroad forum in the Midwest > 4x4 Talk > Chevy Tech
GL4x4 Live! GL4x4 Casino







Search
Reply
 
Thread Tools
Old August 10th, 2009, 09:38 AM   #1
Disturban
Senior Member
 
Disturban's Avatar
 
Join Date: 02-27-08
Location: Lowell, MI
Posts: 2,794
iTrader: (2)
Mentioned: 0 Post(s)
Default Bravada running real bad.

My wife comes home yesterday and said her truck is running bad (2000 Bravada) I jump in and the battery light is on so I pull the ALT take it to get checked and it's bad. I replaced it and thought she was just running on the battery on the way home and that's why it started running bad because the voltage was getting lower and lower. Well charging system is fine now but the truck still runs real bad. It starts right up, idles smooth and if you step on the gas real slow it will rev up fine...if you stab the pedal it will just hesitate and sputter and stay at 750rpm and backfire and will not rev up...if you put your foot to the floor it will never go over 750rpm's. I can drive it but I have to be real real easy on the gas pedal or it just wont go...it's like one big dead spot. First thing I thought of was MAP or TPS sensor but I have no CEL on, I scanned it anyway and no codes. ALSO truck has all new ignition components....Now what? Fuel pump?
Disturban is offline   Reply With Quote
Old August 10th, 2009, 10:28 AM   #2
Kodiak450r
Keep on truckin
 
Kodiak450r's Avatar
 
Join Date: 11-14-07
Location: Waterford, MI
Posts: 5,909
iTrader: (19)
Mentioned: 0 Post(s)
Default

check the fuel pressure just to see. but just because it didn't throw a ses light doesn't mean a sensor hasn't failed. if it's a intermittent failure it won't throw a light till it's a hard failure. i.e has to do it a few times first. try driving it around for at least 15 mins and it should set the light.
Kodiak450r is offline   Reply With Quote
Old August 10th, 2009, 10:32 AM   #3
AGoodBuzz
Senior Member
 
Join Date: 12-09-07
Location: Canton, MI
Posts: 1,557
iTrader: (0)
Mentioned: 0 Post(s)
Default

You may have already done this, but once you reconnect the battery you're supposed to start it and let it idle (no revving at all) for at least 5 minutes for the computer to poll everything and make its adjustments. That comes from a factory service manual anyway.
AGoodBuzz is offline   Reply With Quote
Old August 10th, 2009, 10:46 AM   #4
Disturban
Senior Member
 
Disturban's Avatar
 
Join Date: 02-27-08
Location: Lowell, MI
Posts: 2,794
iTrader: (2)
Mentioned: 0 Post(s)
Default

Quote:
Originally Posted by AGoodBuzz View Post
You may have already done this, but once you reconnect the battery you're supposed to start it and let it idle (no revving at all) for at least 5 minutes for the computer to poll everything and make its adjustments. That comes from a factory service manual anyway.
Yes I did already do this to let the battery charge back up after changing the Alternator. At this point I am 99% sure the fuel pump is taking a dump, I guess it is a very common problem on S10 series trucks. The gas gauge does not work so I am going to change the pump anyway just to get that working right...I was just putting it off.

PS: I did drive it for about 30 miles yesterday to see if maybe something was wet and it would start to run better and no check engine light, I stopped by autozone to scan it on the way home and no codes.

Last edited by Disturban; August 10th, 2009 at 10:49 AM.
Disturban is offline   Reply With Quote
Old August 10th, 2009, 06:09 PM   #5
Disturban
Senior Member
 
Disturban's Avatar
 
Join Date: 02-27-08
Location: Lowell, MI
Posts: 2,794
iTrader: (2)
Mentioned: 0 Post(s)
Default

Well I tested the fuel pressure and got 40psi at the schrader valve while cranking. Truck will not start when fuel pressure gauge is hooked up? Spec is between 60 - 66psi...is that supposed to be at start up, when it's running or all the time? Any idea why it wont start when the gauge is hooked up?

Last edited by Disturban; August 10th, 2009 at 06:19 PM.
Disturban is offline   Reply With Quote
Old August 10th, 2009, 08:01 PM   #6
Kodiak450r
Keep on truckin
 
Kodiak450r's Avatar
 
Join Date: 11-14-07
Location: Waterford, MI
Posts: 5,909
iTrader: (19)
Mentioned: 0 Post(s)
Default

40 is too low. ever change the filter?
Kodiak450r is offline   Reply With Quote
Old August 10th, 2009, 08:12 PM   #7
Disturban
Senior Member
 
Disturban's Avatar
 
Join Date: 02-27-08
Location: Lowell, MI
Posts: 2,794
iTrader: (2)
Mentioned: 0 Post(s)
Default

Quote:
Originally Posted by Kodiak450r View Post
40 is too low. ever change the filter?
Yes the filter is about 3 months old...I just want to make dam sure the pump is the problem before I change it because a new one is $275 and if that dont fix it we have no more money for any other parts.
Disturban is offline   Reply With Quote
Old August 10th, 2009, 08:17 PM   #8
GUINNESS112
Senior Member
 
GUINNESS112's Avatar
 
Join Date: 01-19-08
Location: BROOKLYN MI
Posts: 218
iTrader: (5)
Mentioned: 0 Post(s)
Default

$275 What brand pump is it? I just spent $370 on a Dhelpi pump.
GUINNESS112 is offline   Reply With Quote
Old August 11th, 2009, 05:41 AM   #9
Disturban
Senior Member
 
Disturban's Avatar
 
Join Date: 02-27-08
Location: Lowell, MI
Posts: 2,794
iTrader: (2)
Mentioned: 0 Post(s)
Default

Quote:
Originally Posted by GUINNESS112 View Post
$275 What brand pump is it? I just spent $370 on a Dhelpi pump.
What ever autozone sells. That was the cheapest I could find one for.
Disturban is offline   Reply With Quote
Old August 11th, 2009, 06:24 AM   #10
Nuggets
I fix stuff!
 
Nuggets's Avatar
 
Join Date: 09-15-06
Location: Bay City, MI
Posts: 13,367
iTrader: (13)
Mentioned: 2 Post(s)
Default

I believe that injection system requires about 60 psi to run properly.
Nuggets is offline   Reply With Quote
Old August 12th, 2009, 07:32 AM   #11
radhazard1
Senior Member
 
radhazard1's Avatar
 
Join Date: 03-19-07
Location: North Muskegon, MI
Posts: 165
iTrader: (0)
Mentioned: 0 Post(s)
Send a message via MSN to radhazard1 Send a message via Yahoo to radhazard1
Cool

If your pressure is only at 40 then it won't start. Hooking up the pressure gauge is what makes it not start because your taking away that much more fuel from going to the engine. like making the trip longer for a system that is already starving. I know money is tight but beware of autozone parts. I have had so many of that cheap-ass airtex pump go bad from the zone and a different place that sell them. Carter or Delphi are the way to go and just sitting the products next to each other you can see the quality difference. And even though it's not very old, always change the filter when you get a new pump. This will help when it comes warranty time also.
radhazard1 is offline   Reply With Quote
Old August 12th, 2009, 11:19 AM   #12
Disturban
Senior Member
 
Disturban's Avatar
 
Join Date: 02-27-08
Location: Lowell, MI
Posts: 2,794
iTrader: (2)
Mentioned: 0 Post(s)
Default

Quote:
Originally Posted by radhazard1 View Post
If your pressure is only at 40 then it won't start. Hooking up the pressure gauge is what makes it not start because your taking away that much more fuel from going to the engine. like making the trip longer for a system that is already starving. I know money is tight but beware of autozone parts. I have had so many of that cheap-ass airtex pump go bad from the zone and a different place that sell them. Carter or Delphi are the way to go and just sitting the products next to each other you can see the quality difference. And even though it's not very old, always change the filter when you get a new pump. This will help when it comes warranty time also.
I found a pump at Grand Rapids auto (Junk Yard but they also sell brand new parts) for $190 with a 1yr warranty...I dont know what kind it is but I need to get it running on the cheap right now. I already planned on changing the filter again.
Disturban is offline   Reply With Quote
Old August 13th, 2009, 10:13 PM   #13
Yota Bill
Senior Member
 
Join Date: 08-24-08
Location: Morrice, Mi
Posts: 3,229
iTrader: (11)
Mentioned: 0 Post(s)
Default

Quote:
Originally Posted by radhazard1 View Post
Hooking up the pressure gauge is what makes it not start because your taking away that much more fuel from going to the engine. like making the trip longer for a system that is already starving.
a pressure guage T'd into the fuel system does not take anything away from the system, it just registers how much pressure is there, there could actually be air in the guage and its line, and that wont affect the reading much (not enough to worry about anyway)

did you get the 40 PSI while cranking, or was that the highest reading you got from cycling the key? I would verify the max capable pressure first, if it doesnt reach something above what the running spec is, then look into the fuel pump or regulator (fuel can leak past the regulator, which means low pressure and changing the pump wont fix it)...if max capable is low, then try pinching of or otherwise blocking the return line, if pressure comes up at that point, then suspect the regulator, not the pump.
Yota Bill is offline   Reply With Quote
Old August 14th, 2009, 07:59 PM   #14
Disturban
Senior Member
 
Disturban's Avatar
 
Join Date: 02-27-08
Location: Lowell, MI
Posts: 2,794
iTrader: (2)
Mentioned: 0 Post(s)
Default

40psi was that max I got while cranking it over or with just the key on the PSI did not change. Fuel pump is #1 problem with S10 series trucks so I already got a new pump and filter and will change them out Saturday. If I still have PSI issues I will get a new regulator they are fairly inexpensive.
Disturban is offline   Reply With Quote
Old August 14th, 2009, 11:27 PM   #15
radhazard1
Senior Member
 
radhazard1's Avatar
 
Join Date: 03-19-07
Location: North Muskegon, MI
Posts: 165
iTrader: (0)
Mentioned: 0 Post(s)
Send a message via MSN to radhazard1 Send a message via Yahoo to radhazard1
Default

[QUOTE=Yota Bill;1807259]a pressure guage T'd into the fuel system does not take anything away from the system, it just registers how much pressure is there, there could actually be air in the guage and its line, and that wont affect the reading much (not enough to worry about anyway)

Yeah I think I know what I'm talking about here buddy. Being that I work on cars every day and run my own shop for over 15 years and have seen it happen myself more than once. Maybe stick to the conversation and get your head out of your ass would be nice.
radhazard1 is offline   Reply With Quote
Old August 14th, 2009, 11:35 PM   #16
MISHOWJEEPER
NSFW
 
MISHOWJEEPER's Avatar
 
Join Date: 02-06-07
Location: Lapeer MI
Posts: 2,239
iTrader: (13)
Mentioned: 0 Post(s)
Default

[quote=radhazard1;1808722]
Quote:
Originally Posted by Yota Bill View Post
a pressure guage T'd into the fuel system does not take anything away from the system, it just registers how much pressure is there, there could actually be air in the guage and its line, and that wont affect the reading much (not enough to worry about anyway)

Yeah I think I know what I'm talking about here buddy. Being that I work on cars every day and run my own shop for over 15 years and have seen it happen myself more than once. Maybe stick to the conversation and get your head out of your ass would be nice.
whoa, somebody might need to get laid? he's right about the guage not taking away from the system settle down. How's that shop doing?
MISHOWJEEPER is offline   Reply With Quote
Old August 15th, 2009, 12:06 AM   #17
Disturban
Senior Member
 
Disturban's Avatar
 
Join Date: 02-27-08
Location: Lowell, MI
Posts: 2,794
iTrader: (2)
Mentioned: 0 Post(s)
Default

Has anyone ever used a Spectra Fuel pump? Thats what I ended up getting because that is all I could afford. Just wondering if anyone had one fail? I searched the net for reviews but could not find any.
Disturban is offline   Reply With Quote
Old August 15th, 2009, 02:04 PM   #18
Disturban
Senior Member
 
Disturban's Avatar
 
Join Date: 02-27-08
Location: Lowell, MI
Posts: 2,794
iTrader: (2)
Mentioned: 0 Post(s)
Default

New fuel pump is in and it runs like a champ again...incase anyone is wondering about changing the FP on their Bravada, Jimmy or S10 YES it is a major job! Big time pain in the ass, took 4 hours! The biggest problem was trying to get to all the lines and hoses!
Disturban is offline   Reply With Quote
Old August 15th, 2009, 05:46 PM   #19
blownexploder94
Todd
 
blownexploder94's Avatar
 
Join Date: 11-22-07
Location: South Lyon
Posts: 1,074
iTrader: (6)
Mentioned: 0 Post(s)
Default

Quote:
Originally Posted by Disturban View Post
New fuel pump is in and it runs like a champ again...incase anyone is wondering about changing the FP on their Bravada, Jimmy or S10 YES it is a major job! Big time pain in the ass, took 4 hours! The biggest problem was trying to get to all the lines and hoses!
S10's are easy, you must just be slow. i changed one out on my 2000 in just over an hour
blownexploder94 is offline   Reply With Quote
Old August 15th, 2009, 07:10 PM   #20
Disturban
Senior Member
 
Disturban's Avatar
 
Join Date: 02-27-08
Location: Lowell, MI
Posts: 2,794
iTrader: (2)
Mentioned: 0 Post(s)
Default

Quote:
Originally Posted by blownexploder94 View Post
S10's are easy, you must just be slow. i changed one out on my 2000 in just over an hour
Rear tank or side tank...makes a big difference
Disturban is offline   Reply With Quote
Reply
Great Lakes 4x4. The largest offroad forum in the Midwest > 4x4 Talk > Chevy Tech
Thread Tools

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

Forum Jump



All times are GMT -5. The time now is 05:51 AM.


Powered by: vBulletin, Copyright 2000 - 2012, Jelsoft Enterprises Ltd.
User Alert System provided by Advanced User Tagging (Lite) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd. Runs best on HiVelocity Hosting.
Copyright 2005 - 2012 Cracker Enterprises - Powered by Linux
vB Ad Management by =RedTyger=
Page generated in 0.22611 seconds with 50 queries