Well to begin with, I have recently swapped in a 17,000 mile '05 LQ4 and brand new 4L65-E in my '00 Silverado. I put in new plugs and wires, had to use my old fuel rail and intake because I have a return fuel system but used the newer injectors and coil packs. I had the folowing issues with my old set up but attributed it to the cam and tune, but now I have a bone stock motor and a basic wheatley tune and it goes on even a little worse.

The problem is

A) that sometimes it feels really sluggish and sometimes it feels stout. Often it Won't break the tires loose from a full punch from dead stop and sometimes It will chirp them without even trying.

B) Regularly on cold or short trip start ups it will barely stay running with no power and spit and sputter with slight popping untill you floor it and then it clears up and is usually fine after that until its stopped and restarted. And even then it picks and chooses when it happens, not every time.

C) Completely dies sometimes when coming to a stop every now and then.

So,
Scan for codes. Get O2 sensor code, so I change it.
Code gone problem stays.
I pulled all the plugs which only had about 1500 miles on them , they all look good and identical.
Checked fuel pressure, @52 at idle, pulling vacuum line @60, no fuel in
vac line either. Pressure drops just a tad when you turn key off but hold after that.
Listen to injectors via long screw driver, they all click and at steady similiar
pace.

Next I hooked up my timing light to each plug wire one at a time just to see that they were getting good steady fire. The first three coils on the driver side flashed really slow and erratic sometime going about 1 to 1.5 seconds between flashes. The other 5 all flashed faster and steady. Could this be my problem? Shoudn't it throw a code if there is aproblem with a coil? Is it likely that those three coils all are bad at the same time or could it be somehting else causing them to do this? Anyone got any ideas I am pretty much stumpped.

 

Sorry for such a long post.

 

Anyone???

 

you could try swapping the 3 coils that you suspect as a problem with other ones on the passenger side of the motor and see if the problem follows the coils, if it does then maybe its time to replace them.

 

I doubt that 3 coils went bad, but it couldn't hurt to swap them side to side. I'd be more inclined to think that there's a wiring issue (ie: excessive resistance) in the circuit to those 3 coils. Could be a loose or corroded ground.

 

it sounds like an electrical issue with the sputtering and what not, however dying coming to a stop? thats exactly what mine did if it was in gear. I ended up needing a whole new operating system and to take the throttle blade screw and flipping it upside down so that it kept the IAC counts down. The problem didnt go away untill I took my truck to the local tuner and dyno. (that was also with a Wheatley basic tune...)

Start by swapping the coils over and see if the problem follows. If it doesnt solve anything, definitely take it to a local well-known tuner

 

006rcsb





006rcsb, budhayes3 , 00Silv4.8 : Thanks for the input.

Just rechecked everything, I believe it is all 4 coils on the driver side now. Must have overlooked the 4th somehow.
Light flashes like this on all 4 coils: flash flash flash..............flash............flash flash flash...........flash flash..................flash.............(you get the idea)
Sounds like an electrical issue not sure where to start though. hmmm

 

Like said, i would try swapping them to the other bank and see if it follows. Other then that, is there anything else out of the ordinary when you scan it? are you scanning with hpt or just a code scanner?

 

M.Roberts I went ahead and sent you a PM

 

All I have is a predator to scan it with, which aint much. The only codes as of late are

P0706 Transmission Range Sensor Circuit Range/Performance
( I had to change that switch and it needs adjusting)


Nd041 unknown (what the heck does that mean)

GOt in from work too late to look at it any today.

Got your PM Mr. Wheatley.