Jump to content

Chasing My Tail

steeves2

Recommended Posts

steeves2 Enthusiast

steeves2

Posted
Posted

hi fairly new here and my first post. so here goes. after installing a new battery and alternator i eventually ended up with driveability issues.(might be related mightnot) is there relearning to be done after this? since then ended up haveing the hesitation and shaking underload eg exceleration,uphill. being somewhat old school thaought tuneup time. (160000km) plugs ngk tr55gp gapped to 44 as called for, new wires, fuel filter, pcv valve. never had an issue with the truck since new (2003 4.8l silverado ls) now on start up theres slapping, fumbling, engine shake and to take it down the street the symptoms dont get any better and the nearest service garage is farther then i care to drive it like this. so i end up getting the dreaded p0300 nothing else. ive changed the o2 sensors pre cat, cleaned the throttle body, cleaned the maf sensor. sprayed around the intake manifold with no noticible change in idle, tested fuel press.58 psi with a less then 3 psi drop after five min? i am confussed . and if there is anybody that has information to these causes please help thank you

post-59955-1236278780_thumb.jpg

post-59955-1236278780_thumb.jpg

post-59955-1236278780_thumb.jpg

post-59955-1236278780_thumb.jpg

VR021302 Senior Enthusiast

VR021302

Posted
Posted

Welcome to the forum, and nice f^*king truck

 

Are you sure the batt is good? It can cause these issues if its not strong enough.

DofD Senior Enthusiast

DofD

Posted
Posted

Very nice classic there! :)

 

Like Felix says, get your battery and alt checked to make sure they are putting out enough power. There has been a couple of threads here that have talked about numerous problems that were all related to low power from the battery.

Draenor Senior Enthusiast

Draenor

Posted
Posted

Check your cable connections and wire, especially your ground. If this started after you changed the batt and alternator, start there.

steeves2 Enthusiast

steeves2

Posted
  • Author
Posted

hi thanks everyone for the welcome. well i went over all the electrical bases and all checked out.i was able to have a friend of a friend come over with his scan tool from his garage and through that we are now into the injectors on the driverside bank 1-3-7 were missing so im going to remove and clean the lot of em and see were that goes, if the injectors clean up good and the problem persists im going to lean towards a plugged cat. would having to cats and one pluged creating back press on the one bank? and also going old school again is the timing adjustable or is it just replaceble. if i am correct in assuming theres still a timing belt or chain? well i ll post back tommorrow on my progression if any keeping fingers crossed by the way not sure if i noted my silverado is a 4.8l ext ls 2wd if it helps with addressing this issue and again thanks for the welcome and the responses

steeves2 Enthusiast

steeves2

Posted
  • Author
Posted

hi thaught id let everyone know the out come as it unfolds. i was puzzled by this valve slapping noise as the engin warmed 30-40 secs itwould start and not stop until i shut it down. someone brought to my attention the effects a pre cat exhaust leak would create and to see if i was leaking anywhere. and i noticed my end manifold heads are snapped on the side im having issues with but no leaks. so i gaged my precat o2 sensor hole and low and behold a plugged cat4.5 # back pressure and cool to the touch on the exit. so good ole gm makes you cut and weld your exhaust or replace the duel cat y pipe to the tune of $500. then after i get the=at fixed its time for diagnostic run again to make sure the issues that caused this condition is no longer present. intake leak, injectors, hell the list goes on but for wht its worth a pressure gage pre cat can save a few bucks. thanks to all and i hope this helps some one out oneday

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Latest Articles

  • Posts

    • Grumpy Bear
      Slate Electric Truck

      By Grumpy Bear · Posted

      Not what I said but I can work with it anyway. Complete combustion produces CO2 and H20. When it's cold enough you can 'see' it as water vapor but it is always there and more so the better the tune up. It's physics, not an argument. In a cold motor when the cylinder jacket is below the condensation temperature the water goes to the pan and not the PCV system. Heating the oil moves it from liquid to vapor where it is removed by the PCV system. When and how much depends on temperatures. Of the air, the water and so on. It has little to with the humidity. Water is a combustion product.  
    • Chuck FB
      2 speed transfer case optional now?

      By Chuck FB · Posted

      I can only guess as well that something was clicked on that brought you to the half ton choices by accident. By all means try again and chose the 3500 and sort out that its the cab and box configuration you want and choose four wheel drive ( rather obvious to have a transfer case ) and to make sure the dually isn't chosen. I find or at least did a couple of years ago when I was sifting through the options that it would sometimes jump ahead after choosing the series of truck and in this case 3500 and skip some of the other initial configuration choices and have to watch the heading bar and sometimes back up by choosing the first in the series of option break downs. I think sometimes the computer will remember items that were last chosen and skip over the first part. Anyway go through it all and depending on the trim level chosen and I think the LT is one that may fall into that where the option of having the 4 high auto transfer case can be chosen, where as a High Country doesn't show that option as it just comes with the fancier ( not necessarily better though in terms of potential problems ) transfer case but for sure both transfer case choices are equipped with high and low range in the HD truck segment. Like Newdude said who works at a dealership, its the half tons that are the ones that will come with the single speed unless certain options or trim levels are chosen that add the two speed transfer case but as your looking at an HD, you don't have to worry about that hot mess.    One item that at least didn't show up and not sure if it does yet or not in the HD options on the manufactures pubic website is the upfitter in cab switch option if one is desiring that. Unfortunately its not wired in at the factory but the panel with the switches is on the dash but the wiring harness to be installed gets tossed under the rear seat to be installed by whomever after the fact to complete the installation. 
    • Donstar
      Navigating senior years.

      By Donstar · Posted

      Yesterday we brought home a 6yr  old Havanese dog from a nearby SPCA.  We've had her for 24 hours and we are delighted with how well she is adjusting to her new home.  It  was a huge decision to adopt a dog at this stage in our lives but we believe we made the right choice!   it was reported that her first 6 years were ones of neglect.  I think she's already realizing her life is going to get a whole lot better...  so is ours!    
    • Hoginedgewood
      2 speed transfer case optional now?

      By Hoginedgewood · Posted

      I thought I was building a HD 3500 srw, maybe I was lost.
    • Coastie05
      Which 2027 engine will you choose?

      By Coastie05 · Posted

      No doubt, I definitely agree with you. However, considering the 6.2 and 3.0 have been catastrophically failing with very little miles, I figured I would put trouble free. I’m at 18,4xx and still not a single issue.  

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...