96 4.3 vortec major problems help please
#1
96 4.3 vortec major problems help please
first off i used the search tool and the thread i found with almost the same problem was was closed and never updated with an answer to the problem so please help
ok so heres whats up last month i was running my mom around and it started running really rough like more than it usually did about 20 mins later it died and when i started it after letting it cool down it was knocking badly and didnt want to stay running since then it has knocked heavily and hasnt wanted to run for more than 15-20 mins without dying
heres what ive taken off and inspected:
alternator and bracket-really dirty but nothing wrong with it
distributor-worn distributor gear but otherwise ok
intake manifold (lower and upper) and throttle body- tb is ok upper intake is dirty but ok lower intake is really dirty but otherwise ok
valve covers- dirty outside, clean inside
driver side rocker arms and push rods- good as far as i could tell (rods looked straight and rocker arms looked fine (no un natural bends or knicks or anything))
drivers side head (wasnt able to get it off(all unbolted but wouldnt come off))-filthy
passenger head still bolted on- dirty but not as bad as the drivers side
wouldve kept working but it was about to start raining so i had to stop put the hood back on and put everything up for the day
im a decent mechanic learned almost everything i know from my dad but im stuck. anyone else have this problem and know whats wrong or have any suggestions all help would be greatly appreciated
thanks in advance
drivers side
passenger side
drivers side rocker arms rods bolts and cover
distributor gear
intake manifold
injectors
these two (for cylinder 3 and 5 are really dirty)
also everything will be cleaned before it goes back together once the problem has been located and fixed
ok so heres whats up last month i was running my mom around and it started running really rough like more than it usually did about 20 mins later it died and when i started it after letting it cool down it was knocking badly and didnt want to stay running since then it has knocked heavily and hasnt wanted to run for more than 15-20 mins without dying
heres what ive taken off and inspected:
alternator and bracket-really dirty but nothing wrong with it
distributor-worn distributor gear but otherwise ok
intake manifold (lower and upper) and throttle body- tb is ok upper intake is dirty but ok lower intake is really dirty but otherwise ok
valve covers- dirty outside, clean inside
driver side rocker arms and push rods- good as far as i could tell (rods looked straight and rocker arms looked fine (no un natural bends or knicks or anything))
drivers side head (wasnt able to get it off(all unbolted but wouldnt come off))-filthy
passenger head still bolted on- dirty but not as bad as the drivers side
wouldve kept working but it was about to start raining so i had to stop put the hood back on and put everything up for the day
im a decent mechanic learned almost everything i know from my dad but im stuck. anyone else have this problem and know whats wrong or have any suggestions all help would be greatly appreciated
thanks in advance
drivers side
passenger side
drivers side rocker arms rods bolts and cover
distributor gear
intake manifold
injectors
these two (for cylinder 3 and 5 are really dirty)
also everything will be cleaned before it goes back together once the problem has been located and fixed
Last edited by Junior Russell; 06-05-2013 at 04:12 PM.
#3
sorry its been a few months been trying to earn some money so i can fix this
the rotor bug i brand new as it was back in march the cap is in decent shape
so whats new i found out it was the #2 intake lifter which has since been replaced along with a new rocker arm ball
since then everything has been cleaned and put back together (except the two dirty injector poppets dont know how to clean them if at all)
and now i have a new problem it wont start the fuel pump doesnt kick on so i checked that first and turns out im not getting more than .65 volts to the relay (activator side) and i can bypass the relay and it turns on and runs fine all the wires from the ignition switch except one i think the second from the steering wheel (a tannish color next to the red wire) reads between 11.65 and 12.56 volts
the engine cranks all day and i assume im getting a spark because i can spray some staring fluid in the throttle body and after about 10 seconds itll try to start but then back to cranking
everything ive read points to either the ignition switch or the pcm
i honostly dont know and im at my wits end
any help suggestions etc is more than welcome and appreciated right now
the rotor bug i brand new as it was back in march the cap is in decent shape
so whats new i found out it was the #2 intake lifter which has since been replaced along with a new rocker arm ball
since then everything has been cleaned and put back together (except the two dirty injector poppets dont know how to clean them if at all)
and now i have a new problem it wont start the fuel pump doesnt kick on so i checked that first and turns out im not getting more than .65 volts to the relay (activator side) and i can bypass the relay and it turns on and runs fine all the wires from the ignition switch except one i think the second from the steering wheel (a tannish color next to the red wire) reads between 11.65 and 12.56 volts
the engine cranks all day and i assume im getting a spark because i can spray some staring fluid in the throttle body and after about 10 seconds itll try to start but then back to cranking
everything ive read points to either the ignition switch or the pcm
i honostly dont know and im at my wits end
any help suggestions etc is more than welcome and appreciated right now
#6
Did you forget any sensor plugs when you put it all back together? I had an issue with my 95 that when the cam shaft sensor was shorting out it wouldn't run the pump, but if I jumped it, it would run fine.
#7
I believe the distributor is in right had my neighbor help me set tdc, I lined the rotor bug up with with the little arrow on the distributor, only thing I'm not positive about is if it was compression or exhaust stroke any hints on how to tell the difference? And every thing I unpluggedwas plunged back in, there's no guaranteethat a sensor didn't go bad though thing is if one did how would I track it down?
#8
You can turn the rotor 180 degrees (only other way it can go) and if it starts then it was on exhaust, you have a 50-50 chance of getting it right the first time.
However, im thinking that may not be the problem. Have you done a fuel pressure test? Also, can you tell where the knock is coming from? I think your on the right track with top end, my truck did the same thing but for whatever reason the knock slowly went away. I assumed a suck lifter (which explains rough running) did you just switch your oil type recently??
However, im thinking that may not be the problem. Have you done a fuel pressure test? Also, can you tell where the knock is coming from? I think your on the right track with top end, my truck did the same thing but for whatever reason the knock slowly went away. I assumed a suck lifter (which explains rough running) did you just switch your oil type recently??
#9
Yes I did a fuel pressure test about a month before all the problems started, and it was at approx 50-51 psi. I ended up buying a fuel filter and swapping it out and that was fixed. The only problem I found when I tore it apart was: the number 2 intake lifter was bad or stuck or something. I've replaced that, replaced a rocker arm ball that I lost somehow. No i was running Pennzoil 10-30 before the break down now I've got quakerstate 10-30 after the repair and rebuild
Last edited by Junior Russell; 07-30-2013 at 10:40 AM. Reason: finishing post
#10
ok so i did quite a bit of reading today and most of what i found is also pointing to the possibility that the ckps went out being that pretty much everyone on this site knows their stuff so i figured id ask could a bad ckps be causing all of my new problems? is it worth looking into? mind you the old girl was down and out for 2-3 months while i was repairing her and it started completely out of the blue
thanks for everyones help thus far and any and all help in the future
edit~also completely off topic but just out of my curiousity what is the shaft between the heads?(note picture 1-3 for reference)
thanks for everyones help thus far and any and all help in the future
edit~also completely off topic but just out of my curiousity what is the shaft between the heads?(note picture 1-3 for reference)
Last edited by Junior Russell; 08-02-2013 at 09:21 PM.