Again, I have a 1990 K5 Chevy Blazer with the 350 TBI. (SQUARE BODY TRUCK)
Anyways, the engine was rebuilt fully in 2002. There is 20k on rebuilt. Here is problem:
The engine has alot of power, shifts smooth ect. However it idles rough on ocasion. More rough the ever.
When you start it up cold it runs fine, when it warms up it idles fine, when you drive it it fine BUT when I shut it off and restart it say anywhere between 10 mins and 3 hrs. it runs very rough almost like it missing. when you put it in gear and drive there will be a very slight hesitation and then it goes and no more problems/ sometimes when i stop it smooth and sometimes it rough. It idles really low to the point you cant hear the engine but you feel it run rough. the truck kinda vibrates.
Here is what i have done.
New plugs which were gapped correctly,new wires, cap and rotor.
Checked timing and is dead on. New air cleaner, pcv valve,
map sensor, tps sensor, oil change, changed gas, thermastadt, went from a 195 to a 160 degree but still same results. Never overheats, decent gas milage, doesnt smell rich. No SES light comes on.
Like I said it takes off when you accelerate with no problems. It just like to run rough only when engine is hot and when you shut it off and restart it.
Also, if you gooses it when its rough,it will straighten out but start doing it again .
Anyways, the engine was rebuilt fully in 2002. There is 20k on rebuilt. Here is problem:
The engine has alot of power, shifts smooth ect. However it idles rough on ocasion. More rough the ever.
When you start it up cold it runs fine, when it warms up it idles fine, when you drive it it fine BUT when I shut it off and restart it say anywhere between 10 mins and 3 hrs. it runs very rough almost like it missing. when you put it in gear and drive there will be a very slight hesitation and then it goes and no more problems/ sometimes when i stop it smooth and sometimes it rough. It idles really low to the point you cant hear the engine but you feel it run rough. the truck kinda vibrates.
Here is what i have done.
New plugs which were gapped correctly,new wires, cap and rotor.
Checked timing and is dead on. New air cleaner, pcv valve,
map sensor, tps sensor, oil change, changed gas, thermastadt, went from a 195 to a 160 degree but still same results. Never overheats, decent gas milage, doesnt smell rich. No SES light comes on.
Like I said it takes off when you accelerate with no problems. It just like to run rough only when engine is hot and when you shut it off and restart it.
Also, if you gooses it when its rough,it will straighten out but start doing it again .
Aug 8, 2009 at 2:45 PM
