SkippyDoodle

I am having a problem with my 1998 Chevy S-10 4.3l V6/4x2

The problem started without any warning when I turned it off and it wouldn't start back up. I had it towed it to a friend's house. I sprayed ether and it started up and stayed running well for a week.

Today it happened again. I shut off the truck and it wouldn't start back up again. I tried ether again and now it starts but won't go above an idle.

While its running I can hear a loud vacuum noise from the top of the throttle opening (the back side top). When I stick my finger down in the hole (don't know what it's called but it's a throttle port on top of the engine) the idle smooths out. When I take my finger out it idles roughly again and stalls out.

The vacuum sound is coming from the upper metal part of the throttle body itself.

Any thoughts on what it might be, what I might check? I need to fix this fast since it is our only vehicle right now.

Siliconasp

I'm guess from your description that you are referring to the top half of the Throttlebody Intake above the intake gate. if so, then the issue could be a Throttlebody Position Sensor (TPS Sensor) is the cause of your issue. If this Sensor has failed you should have a Check Engine Light on and Should also have a rough idle as it is no longer sending Throttle Increments information to the ECU correctly. You will need to replace this part.

Other then that check the gas petal cable on the lpassenger side of the throttlebody as you are in front of the truck. make sure that they are tight and have not come out of the cradles. If so tight the cable and cradle.

Lets hope like hell it not you Air Intake Plenum Gasket. Since you said it was at the time of the unit and not the bottom, this would be a longshot.

One last thing, make sure the EGR return hose from the EGR Valve on top of the passenger side valve cover is connected to the back of the Air Intake Housing Tubel. This can also cause a vacuum leak and the condition you are stating..

http://www.autozone.com/autozone/cat...&parentId=59-0

Not very expensive, and only take a few minutes to replace with a simple screw driver.

gumbute

I also have the same problem just started today. I went to back out of my yard when the truck started to run rough when i started down the road i couldnt get over 30 klicks with my gas pedal all the way to the floor. Same sound as if im getting a loud vacum leak.truck runs realy rough.