The MAP sensor is located on top of the plenum to the right of the throttle body. It is about 1.25"x3" LxW.

It is possible that the MAP sensor is causing the problem, but I would clean the EGR valve first to see how dirty that is.

Disconnect the battery for 10-15 minutes.

 

Ok i read one of your forums on how to clean the EGR so i guess ill try that first since the sensor is kind of expensive. Ill let you know what happens.

 

I have a 1994 blazer 4.3L w 4 door 4x4. I have been having problems with stalling and loss of power. When i drive ill be going and it will start stalling out and the more pedal i give it the more power i loose. If i just floor it all the way it will eventually die. Then i will have to stop restart the truck and it just does the same thing again every 5 to ten minutes and i gets worse everyday.Kinda seems to acts up worst going up hills taking off from a stop and sometimes when coming to a fast stop I have changed fuel pump, sending unit, fuel pump wiring harness, fuel filter, cleaned out the tank,and sea foamed fuel system so im guessing thats clean. Fresh oil change(valvoline oil)/ wix filter, seafoamed it before oil change , new cap and rotor new plugs all gapped properly and wires. Before my ses light was not on and i had been getting a 12 code when i used my jumper which means nothing. Today the light finally came on now i am getting a code 23 = DTC 23 - Accelerator Pedal Position 1 Circuit Range Fault. Im good with cars but im 19 im still learning ive never got to this problem yet. My grandpa died & i just got the blazer im new to the 4.3 so... can anyone tell me what this code means??? what do i need to do to fix this? Please anyone this is my only RIDE right now!!






Ok that was my original post i was told told it could be my FPR changed that and cleaned my EGR still no luck anybody got any ideas could my loss of power be coming from my cat it is making a rattling noise

 

Lets please keep this in your original thread... Merging with the original thread.

If your cat is rattling, that is only going to get worse. It is possible that it already is affecting your performance.

 

how does it idle?

 

So you have replaced the sensor. Is DTC 23 still popping up? If so, then you need to start checking for a cut wire or short.

 

No im not getting any engine code anymore. I cleaned and inspected the Egr it wasnt very dirty and it seemed to be opening and closing fine. when i took the plenum off i saw washing on the passenger side so i got a new FPR still no luck. Yesterday i replaced the Injector spider and intake gasket and it was still doing the same thing. I read some threads about the cat and i think this could be my problem. Today i Drilled a hole straight through the middle of the cat. I was told this would relieve some pressure if that was the problem. I could notice a little difference but not much AND IT WASNT TOO LOUD, the inside of the cat is white/ a little chard and and all the mesh looks to be melted together and i dont see how anything could pass through there Is this normal? I guess tomorrow im going to cut the cat the rest of the way off and change the plugs and see if there is a difference. I was told that since my FPR was leaking and making it run rich its a possibility it could have messed up my cat and plugs. Is this true?? Ive about had it with this truck! If i cant get it fixed soon im selling it!!!! For something that RUNS! The problem has gotten worse and worse to the point i cant drive no more. I loose acceleration till it dies then i start it up and i got power for 30 seconds then the same thing more pedal i give it the more it sputters untill it dies.Its getting worse now its getting hard to start. I just got this! my grandpa never had any problems with it! PPPPPPPPLLLLLLEEEEAAS HELP!!!!!!!!!!!!!!!