P0300 on 2001 Silverado - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


GMC/Chevrolet Truck/SUV When starting new posts, please specify YEAR, MAKE, MODEL, ENGINE type, and whatever modifications you have made.

Reply
 
 
 
Thread Tools Search this Thread
Old 05-30-2012, 02:52 PM   #1
Senior Member
Posts like a Turbo
Thread Starter
 
SilverSleeper8704's Avatar
 
Join Date: Jan 2010
Location: "Upstate" NY. Where cows outnumber people
Posts: 441
Thanked 1 Time in 1 Post
SilverSleeper8704 is on a distinguished road
Default P0300 on 2001 Silverado

Hey gang. I have been fighting a P0300 general misfire for awhile now. My mechanic did a clean out of the injectors and fuel system. Ran better for awhile, but its back. No particular time or weather or temperature related. However, it does seem more likely to kick in if I use tow/haul mode. The cel comes on flashing for about a mile or so, then goes out. The P0300 always shows up as a pending code.
Truck has 91k on it, 5.3L, 4WD. Any clues where to look next? My mechanic checked over the plugs and ignition. Seems to be related closely to using the tow/haul when going up and down hills on backroads on my way to work. It hasn't set off while not in tow/haul yet. I wonder why it only seems to do it in that setting? I don't tow anything yet, but that setting seems to be easier on the trans when I'm on the backroads. All its doing is holding the gears longer and keeping the converter unlocked. I'm not putting a bigger load on it. So I have no idea why is only happens when its in the other mode.
SilverSleeper8704 is offline   Reply With Quote
Old 05-30-2012, 03:38 PM   #2
Senior Member
True Car Nut
 
jwfirebird's Avatar
 
Join Date: Dec 2009
Location: western,ny state
Posts: 9,616
Thanked 563 Times in 481 Posts
jwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond repute
Default

if the ign has been checked next for me would be to check fuel pressure, lack of pressure from pump, filter, or regulator.
jwfirebird is offline   Reply With Quote
The Following User Says Thank You to jwfirebird For This Useful Post:
WilliamE (02-05-2015)
Old 05-31-2012, 08:47 AM   #3
Senior Member

True Car Nut
 
2kg4u's Avatar
 
Join Date: Sep 2006
Location: Windsor, Ontario / Detroit, Michigan
Posts: 4,804
Thanked 220 Times in 181 Posts
2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of
Default

Coils, plugs and wires are typically the first things to check. If your mechanic was thorough in checking these out the next area to check is everything related to fuel pressure. If you have not changed the fuel filter in a while, start with that. Next, have your mechanic check fuel pressure at the rail versus spec pressure for your engine. If pressure is low, you could have a tired fuel pump. This could cause random misfires.

Once you rule out spark and fuel, you may be into a mechanical issue such as a broken valve spring.
2kg4u is offline   Reply With Quote
Old 02-05-2015, 01:22 AM   #4
Senior Member
Posts like a Turbo
Thread Starter
 
SilverSleeper8704's Avatar
 
Join Date: Jan 2010
Location: "Upstate" NY. Where cows outnumber people
Posts: 441
Thanked 1 Time in 1 Post
SilverSleeper8704 is on a distinguished road
Default

Wow, I had almost forgotten about starting this thread! Searched a Silverado Misfire, and there it is...
Been really busy, with life, work, etc, but glad to see this site is still up and running!!

Still throwing this code, even 3 years later.. who knows why.
Haven't really done any modifications to the truck. Just kinda kept it going, so haven't changed anything that should affect it.
Tow/Haul still sets it off
Manual shift into 3rd or 2nd sets it off
Will never misfire if left in OD and out of tow/haul.
Had a few people look at it, make computer recorded test runs with it, yet somehow it still persists.
Is it even possible that the computer needs to be reprogrammed? That somehow the program is corrupted, which is only set off by the transmission being in an alternate program mode?
I'm perplexed.
Was hoping it would either sort itself out in time, or whatever the problem is, would get worse and I could figure it out, but I'm still just as stumped as I was when I started this post.
Anyone?
SilverSleeper8704 is offline   Reply With Quote
Old 02-05-2015, 07:35 AM   #5
Senior Administrator


Certified Car Nut
 
Mike's Avatar
 
Join Date: Jul 2003
Location: Horseheads, NY
Posts: 15,641
Thanked 995 Times in 772 Posts
Mike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond repute
Default

Tow/haul uses different set of tables in the programming. Everything from how long the trans stays in each gear, trans line pressure, and it even has a different program for how the engine runs. With that said, if the engine is told to work harder using the tow/haul and your ignition system isn't up to par, then you could experience a P0300.

Even though you are at 91K, 100K is NOT the magic number for your first tune up. Ignition components can fail out of the box. I suggest a full tune up of plugs and wires.
Mike is offline   Reply With Quote
The Following 2 Users Say Thank You to Mike For This Useful Post:
SilverSleeper8704 (02-18-2015), WilliamE (02-05-2015)
Old 02-05-2015, 12:47 PM   #6
Senior Member

Certified GM nut
 
Tech II's Avatar
 
Join Date: Feb 2014
Location: Worcester, Ma.
Posts: 2,141
Thanked 779 Times in 608 Posts
Tech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond reputeTech II has a reputation beyond repute
Default

Still could be secondary ignition.....towing creates a greater "load" on the system.......

For example, on most GM cars, you tend to feel that misfire, when the TCC engages in fourth gear, while slightly accelerating up a grade......step on the gas, and the TCC disengages, load, decreases, and the misfire is gone....
Tech II is offline   Reply With Quote
The Following User Says Thank You to Tech II For This Useful Post:
WilliamE (02-05-2015)
Old 02-05-2015, 08:30 PM   #7
Senior Administrator


Certified Car Nut
 
Mike's Avatar
 
Join Date: Jul 2003
Location: Horseheads, NY
Posts: 15,641
Thanked 995 Times in 772 Posts
Mike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond repute
Default

^Exactly
Mike is offline   Reply With Quote
Old 02-18-2015, 12:24 AM   #8
Senior Member
Posts like a Turbo
Thread Starter
 
SilverSleeper8704's Avatar
 
Join Date: Jan 2010
Location: "Upstate" NY. Where cows outnumber people
Posts: 441
Thanked 1 Time in 1 Post
SilverSleeper8704 is on a distinguished road
Default

Thanks guys. But actually, now the truck has almost 140k on it. Did exactly the same thing as it did with 91k. No worse, no better.
It does seem to be better in colder weather. Since we've been hovering around 0 the past week for highs, it seem to take longer to trip that code. I do drive around in 3rd, especially on the back roads, and the colder it is outside, the longer it will take to trip. Some days driving into work, it never sets.
As far as the load is concerned, I don't actually tow anything. But, even if I have the truck playing in the snow in full 4x4, it doesn't trip the code as long as I don't put it in 3rd. Also, I did notice that on long downhill stretches, if I use 3rd for engine braking, without touching the gas, it doesn't trip the code either.
SilverSleeper8704 is offline   Reply With Quote
Old 02-18-2015, 09:33 AM   #9
Senior Member
True Car Nut
 
jwfirebird's Avatar
 
Join Date: Dec 2009
Location: western,ny state
Posts: 9,616
Thanked 563 Times in 481 Posts
jwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond repute
Default

take a look at the TB blade on the back too and see if it looks carboned up
jwfirebird is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
2001 Montana P0300 Kazko Pontiac 10 03-12-2013 01:35 PM
GPS units not functioning right in 2001 Silverado? SilverSleeper8704 Audio (and aftermarket electronics) 18 06-17-2012 09:19 AM
2001 Chevy Blazer P0300 misfire wayneo28088 Chevrolet 2 09-07-2011 05:02 AM
DTC P0300 Engine Misfire Detected Wargamer 1992-1999 26 05-01-2005 02:57 PM
2001 Chevy Silverado Problems Lowrider0308 Lounge 5 02-03-2005 09:16 PM


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 Off
Refbacks are Off



All times are GMT -4. The time now is 07:10 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.