1989 s10 4 cyclinder - motor not running smoothly

[e5028818]

the truck starts up up and runs great for about 10 minutes
then it seems like its missing on the firing engine idles ok but when you give it a little gas it runs but spits and sputters

i changed plugs , coils , wires , cap rotor - engine getting lots of gas
is it posssible my time gears are gone

thanks for any tips or info

[OverBoardProject]

I would imagine that you checked the ignition timing.

If you pop the valve cover off, and turn the engine back and forth a little by hand (this can usually be done with the fan belt, but don't force it) you can observe how far the crankshaft turns before the valves start moving... This should give you a good idea if yout timing set is worn out.

A compression test is never a bad idea when you have problems like that

[e5028818]

i did check the timming it was off by a lot
and i set it on the timming specfied then the truck would hardly run
and the manifolds turn red hot

In order to get it idling correctly i had to set it of its timing

so my timing gears are most likely worn out

Is that coorect

Thanks for an answer

Originally Posted by OverBoardProject

I would imagine that you checked the ignition timing.

If you pop the valve cover off, and turn the engine back and forth a little by hand (this can usually be done with the fan belt, but don't force it) you can observe how far the crankshaft turns before the valves start moving... This should give you a good idea if yout timing set is worn out.

A compression test is never a bad idea when you have problems like that

[OverBoardProject]

I've also seen the timing marks in the wrong place, Theres rubber in there that rots... They ocasionally slip on the shaft, when the keys shear, and even more often they are replaced with the wrong ones.

Sorry to say You will probably have to pop the left valve cover off to investigate further

[OverBoardProject]

Sorry I was thinking 6 cylinder, but you will still probably have to pop the valve cover

[BlazerLT]

Originally Posted by e5028818

i did check the timming it was off by a lot
and i set it on the timming specfied then the truck would hardly run
and the manifolds turn red hot

In order to get it idling correctly i had to set it of its timing

so my timing gears are most likely worn out

Is that coorect

Thanks for an answer

Ummm....

You then didn't set it properly. You need to disconnect the timing advance wire from the PCM under the dash when you set the timing.

Then once it is set, you reconnect the wire and away you go.

[e5028818]

Originally Posted by BlazerLT

Ummm....

You then didn't set it properly. You need to disconnect the timing advance wire from the PCM under the dash when you set the timing.

Then once it is set, you reconnect the wire and away you go.

I had a look under the dash couldn't find or don't really know what i, m looking for

can you give a an idea where - and color of the wire

thks