Hi folks,

Noticed yesterday on a drive from Houston back to Austin that my 2001 Blazer would occasionally have a "hiccup" or feel like maybe it was dropping a cylinder every now and then. Funny thing is, that when I got home and went out later in the evening, it didn't do it, and it hasn't done it this morning.

I am planning on doing a tune-up, as it runs a little rough at idle and I don't know when it was done last (just got the vehicle).

Any ideas about what the issue is? Hoping a tune-up will solve it.

Thanks
Craig

 

use a scan tool and look at the misfire counts for each cylinder and that will pinpoint the issue and hopefully save you some money and time

 

If your gonna do a tune up while you have the cap off pull the distributor and be sure the gear isn't getting too worn. Just be sure to mark the rotor position for when you put it back in.

 

My 01 does this also. My scan tool doesn't pick any misfires up. To me it feels like a sudden burst of wind hitting the truck head on for just a split second kind of deal. If that makes sense.

 

Check your distributors you can have a misfire without triggering a check engine light it has to register as a fault for a certain amount of times before the light comes on. I had the same problem sometimes the light would be on when it would miss really bad after babying it I could get it to shut off but if I hammered on it to hard it would trigger it cause my dist gear was only wore down on about a quarter of it and at that time I had no idea what was causing it and never thought it could be something so simple. it's worth checking out.

 

Now that you guys mention it, my 96 has had this hiccup problem for 4 years (LMAO!). I never knew what it was. Doesn't do it all the time. It's almost as though you turned the ignition off and on real fast.

 

My 02 had the hiccup you describe when cruising on the freeway. I pulled the code for a misfire on cylinder 4 so I did a full tune up and it still didn't go away. Everyone I talked to said it was the injectors at that point. Rather than replacing the injectors, I run the Lucas fuel injector cleaner at every other fill up and the hiccup hasn't returned.