I have a 93 S-10 Blazer, 4.3 CPI, that runs pretty well for the MOST part but I get a code 32 1-2 times a year with it on long drives. I never get a code on regular day in and day out driving. The only time I get it is on long drives on the interstate or hauling a camper I own. I have removed the old EGR several times over the last 3 years and checked it, little to no carbon but I cleaned it and went on until another episode which would be months. I finally replaced the EGR 2 months ago and thought maybe the old one was just failing to keep up but on a recent trip of 120 miles towing a small camper it acted up and gave me the code again, and idled poorly for about 10-15 minutes. Then cleared up. I got the code again finally just 2 weeks later. I ran seafom through it last year, and again I have rarely seen any carbon build up. Just curious if another thing such as CPI, cat converter, etc. could be causing this on a load. When the motor is stressed I see this, but otherwise no problems. Tuned up 8 months ago, cap, plugs, fuel and air filters, you name it. 02 sensor replaced a year ago. I would say that the power is not the greatest on the highway, especially when towing. It just does not have the pep my son's Explorer had, even with a smaller engine. Appeciate any thoughts.

Code 32 is EGR valve system error.
First check or test for that code is the egr VALVE SOLENOID.
Check vacuum lines and solenoid switching and there is a little oam filter inside it that gets dirt in it.
MT

This engine has a digital EGR valve. In this case, I would try and find a screened EGR gasket, I don't remember, I think its tomco that makes it if I am not mistaken. This will usually solve those intermittent EGR problems.

I have heard of the screen, but since I see almost no carbon and this EGR is new, I thought perhaps something else might be triggering it. Maybe there is carbon way up inside where I can't see.... I will look into that and see if I can find one. As for the first response, what kind of filter are you referring to??? I have checked all vacuum lines, new EGR. What else is involved that would have a filter?

I have heard of the screen, but since I see almost no carbon and this EGR is new, I thought perhaps something else might be triggering it. Maybe there is carbon way up inside where I can't see.... I will look into that and see if I can find one. As for the first response, what kind of filter are you referring to??? I have checked all vacuum lines, new EGR. What else is involved that would have a filter?

It it a electronic or vacuum controlled egr valve?

The CPI (w) engine no doubt is a digital valve. The CPI's only came with the digital valve, along with later the CSFI engine.

Yes it is a digital EGR. I will remove it and see if anything looks odd. Runs fine now so maybe it is slipping small chunks during long or stressful pulls.

Yes it is a digital EGR. I will remove it and see if anything looks odd. Runs fine now so maybe it is slipping small chunks during long or stressful pulls.

Sorry about the vacuum controlled one.
I did not read far enough on it.

The Digital is bad about picking up carbon balls/chips under plunger and as said the screen gasket will help on that end.
Other problems is wiring and plug in's or bad EGR valve and sometimes PCM control.
Even a new one could be bad.
To test it you need a scanner to control the egr valve and a volt/ohm meter to ohm it out.
Check your private e mail for a code 32 repair chart.
Good Luck MT