93 blazer chugging

I am new to this site, but what I can see it's one of the best I have came accross. Here's my problem. Couple weeks ago I was driving, ses came on and read egr problem. Replaced that, ran fine for a couple weeks, now seems to be the same thing, but no codes reading. When the truck is cold will run for a very short time,then all of a sudden it starts chugging, the engine will surge, and back off like it's going to die, and it does. Took out the egr again and cleaned it, the problem still persists. I might add that all the necessary tuneup things have been done in the last week. It is a 4.3 cpi. help please. thank you

Pull the upper plenum and check for washing, sounds like you're dumping fuel. Also check the fuel pressure..

Thank you, I will check that, I will add that the fuel pump, gas tank and everything else that could be changed was changed last year. Pulled the egr last night, and ran it with it off and the car continued to surge, then go back down, it didn't shut off but would not stay idled at a low speed, very high idle.

Thank you, I will check that, I will add that the fuel pump, gas tank and everything else that could be changed was changed last year. Pulled the egr last night, and ran it with it off and the car continued to surge, then go back down, it didn't shut off but would not stay idled at a low speed, very high idle.
I have a '93 CPI. How's your gas milage? When my CPI took a dump, I went from approx. 330 miles to a tank to under 200 miles to a tank of gas. I had to replace the Nut Kit inside the Plenum. The thing was dumping gas into the plenum.

gas mileage seems fine. today took out the egr, cleaned it, took out the iac, which is only 1 year old, cleaned it. stupid question but, what is the plenum? I am a woman and alot of this is new to me, but I am trying to do the best I can. It doesn't want to stay running keeps shutting down. when I try to give it gas, I have to play with the pedal to try to keep it going, but it still shuts down. This thing is costing me an arm and leg to keep going, in the past year have replaced so many new parts. And I think I said before all the necessary tuneups have been done this last week. not sure what to try next. Thanks for your input.

gas mileage seems fine. today took out the egr, cleaned it, took out the iac, which is only 1 year old, cleaned it. stupid question but, what is the plenum? I am a woman and alot of this is new to me, but I am trying to do the best I can. It doesn't want to stay running keeps shutting down. when I try to give it gas, I have to play with the pedal to try to keep it going, but it still shuts down. This thing is costing me an arm and leg to keep going, in the past year have replaced so many new parts. And I think I said before all the necessary tuneups have been done this last week. not sure what to try next. Thanks for your input.

The upper plenum is the top of the intake... 9 bolts (10mm)...

thats what I thought, but before i did anything I wanted to be sure. Thanks

no gas pooling anywhere. But here's another question? If the egr was so carboned up, could there now be problems with the cat converter? The reason I ask is because I have had the rotten egg smell a couple times, and it sounds like there is something in the cat when I rev the engine. It has been suggested to clean out the intake manifold in case there is a carbon buildup. any suggestions on a good way to do that? Thanks in advance

Is it clean on either side? (gas may not be pooling) And if you were running that rich for a while and the exaust smells like rotten eggs and it rattles, it's time for a new cat

now I'm confused. car started showing a code today after much work. seems to be coming up code 23. but according to my book, and the automotive center, there is no code 23 on this year, model etc.. what gives? any ideas? unless there has been some change or something to this car before I got it? help. anyway this code shows as (MAT) sensor on the other code readings. I'm told there is no mat sensor for that car, and they call it a MAP sensor, same thing?

Code 23¥

MAT Low Temp
Indication

Sets if the Manifold Air Temperature Sensor, Connections or Wires are Open for 3 Seconds.

You may have forgotton to put it back on or it's not on properly when you pulled the plenum..

On closer look, there is gas pooling. More on the drivers side, scant amount on the passenger side. Does that mean new cpi? or nut kit?

Both at this point... Driver side is the nut kit, passenger is the CPI, replace them both.

o.k. next????? Had the new nut kit, and new c.p.i put on everything is back together. also added new TPS. same problems. now what???? here is a list of everything that has been done.
sparkplugs
wires
map sensor
tps
new cap/rotor
coil pack
egr
plus the nut kit
and cpi.
still continues to die. will not stay running. no codes coming up. any ideas what to try next? I said before, the gas tank, sender, strainer, and fuel filter are new, about a year old, except for the new filter. somebody out there has to know whats going on.