Hi I'm new to the forums and have reciently bought a 98 blazer. I didn't not notice the problem when I drove it but now when I stop it'll sometimes sputter and stall out on me. The check engine light has not come on and the only time it hesitates is when I take off but not that often. It also makes a rattling noise at times when I am on the gas. If anyone has any insight or might know what is causing this it would be greatly appreciated.

 

This is commonly a symptom of a clogged EGR valve (barring an issue with the ignition system - plugs/wires/cap/rotor). The valve can be removed and cleaned. What happens is carbon buildup can flake off the inside of the exhaust gas supply tube to the valve and get stuck in the valve itself, holding it open affecting idle and overall engine efficiency. A new gasket would be required if you plan on removing the valve and cleaning it. They make a gasket that has a screen over the inlet port to combat this issue.

If that doesn't fix things, you may want to have a look at the throttle body, specifically the IAC (idle air control) valve area. I would remove the TB and clean it very well, removing the IAC valve and cleaning the associated bore and seat.

Still not fixed, it may be time for a tune up (plugs, wires, cap, and rotor).

Let us know how each one of these steps goes and the results after the R&R.

 

Swartlik maybe clogged cat?

 

no clogged cat would be constant not intermittent at least in my experience it has been.

 

wrong thread

 

Word I'll try that this weekend, my buddy thinks it might be the fuel pump. I'm bring it down to him and we're going to do some testing and looking but I'll let y'all know how it goes.

 

So I have not had a chance to pull everything apart and clean it but I fixed a vacuum leak and it does not stall anymore. There's a few things I'm going to clean or replace soon. Want to keep inching at it until it runs perfect.

 

Where was the vacuum leak? I'm having a very similar issue that just started. Trying to limp it along until the rain clears up.