Noticable stagger


#1

My poor old Chevy S-10 is showing more signs of it’s mileage. Whilst driving, it seems to shudder or stagger when I’m driving on level or downhill roadway. It’s especially noticable when holding the RPM and MPH constant (around 2000 RPM or 65 MPH). It does not occur when traveling uphill,and holding the RPM/MPH constant.



It also does not stagger or shudder when I accelerate rapidly,or while holding the throttle open.



I should note that during start, it sometimes takes several attempts to crank the engine. However, sometimes, it starts as soon as I turn the switch.



One last note: I had to remove the fuel lines and distributor to replace the intake manifold gasket a while back. I was not able to replace the fuel line O-rings (couldn’t determine the correct one to use when I received the “intake manifold gasket kit”). I also had a problem when trying to reinstall the distributor. I accidentally turned the distributor, which threw out the timing. After a little research, I found out how to time the thing and HOPEFULLY got it right.



Any suggestions on what is going on? Or have I goofed when I did the previous work and caused the problem? I myself am leaning towards the latter, cause this was not occuring before I did the work, but I don’t know where to start or what to correct.



Thanks ahead for any input.


#2

You need to take the little truck to a mechanic because the problem can be in one or more of the areas that you worked on. The entire maintenance procedure will have to be backtracked to find the problem(s).


#3

Give us a little more information. What year is this S-10? What engine do you have? Exactly how many miles is on this engine? When you did the timing did you disconnect the “spout” connector?

With a little more information we might be able to help.


#4

2001 with 275,000 mi. It has the “Vortec” V-6 4.3L.

I don’t know what a “spout” connector is. When I timed it, I positioned the crank so that the balancer lined up with a mark specified by “Chiltons book” trying to be sure that the #1 cylinder was on the compression stroke. Then installed the distributor in the position specified, once again by Chilton, being sure that the distributor fit down into the oil pumps’ slot. It seemed like the slot moved every time I put the distributor in. The thing that seemed hardest was anticipating the rotation of the distributor while its and the drive gear for it meshed together.

When it was all said and done, it cranked and ran fine for a while, then started the staggering problem after a few days of driving. Is it possible to get the distributor off one gear tooth allowing to run, but run rough?

Let me know if you could use more info. Thanks for looking into it.


#5

I had a friend tell me that the fuel pump could be “going out”. Could this be true? I was forced to replace the pump several thousand miles ago. When it went out, it didn’t give me any warning (ie “going out”) it immediately shut down the truck. So, again, could this be a probable cause?


#6

I assume you mean the fuel pump. Put a gauge on it and see what it is doing.

Pumps can but don’t necessarily fail suddenly.

Certainly verify that the timing is correct.