I have a '96 Blazer 4.3l, it will start rev upfor 3 seconds then die. Ihad teh fuel pump replaced recently, I ahd to start every morning with a splash of gas in the throttle body. Theblazer hasn't been right since the fuel pump was replaced. I've been given some suggestions like chexck for vacuum leaks, the cat is bad, etccc... all these check out OK.

I had to drive it home the other day from a friends house, the cops put a tow sticker on it. It would run Ok at 3000rpm and over, but would try to die if I went below that (Fun 15 mile trip). when the vehicle is not moving, you have to constantly pump the accelerator to maintain 3000r's or it dies. when driving I was able to use the gear shifter to keep the r's high.

Any ideas?

 

Howdy,[sm=welcomesign.gif]Sounds like a bad fule pressure regulator not letting gas get to the fule metter/block. its a small part under the plenum, thay can get clogged or blow out spilling fule into the intake after installing a new fule pump. this is my first educated guess, also have the coads scanned at a local parts store. the idel positionsensor may also bethe problem, the scanner should pick this up.

 

Thanks for the help,

Where do I find this? I looked for fuel leaking around the intake where the fuel lines enter the intake, None found. I do suspect that the guy that replaced teh fuel pump at some point disconnected these lines (at the intake end)and dropped an o-ring and possibly a spacer. I'm not sure if he found them and put them back in or not, but no leaks.
I cleaned the MAF last night with CRC contact cleaner, this did not help. I then went out and rented a Dignostics code reader, it showed a P0101, I erased the code, and it did not come back after several times restarting the engine.
Still guessing and grabbing at straws.

 

Howdy, ok first i would suggest a Haynes manual, it will help with gitting to the fule pressure reulator.
Second, the regulator is locayted in under the plenum below and at the rear of the fule meter block where the fule lines go. Third, make sure the o ring is installed. this is a pressurized systom at 63psi and any air leek will also cause problems. Im not sure why the person installing the fule pump would have disconected the fule lines at the meter block, it has nothin to do with the fule pump. If you go to Rustyd on the fifth page of this posting where hes asked for pleeess help, there's more on the regulator subject.
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either fuel press reg as suggested or throttle position sensor.


when the fuel system goes bad, it can be a long and costly up hill battle.

 

I Found teh problem, it was a crack in the upper plenum, it was in the rear next to the distributor so it was not noticable until I removed it.

Thanks to all that helped.

 

Your welcome, Glad you found the problem
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I have a 1996 1500 2WD 4.3L V6. I have the same problem as stated above so I will not wast the time to repeat. Last weekend I pulled the top intake off and replaced the spider assemble I think it is called the CSFI the original part. The new part was called MFI I think but the only one they sold not cheep. The Truck ran great for 3 days now I am having this problem. I can't even keep the darn thing running. I checked all over for vacum leaks and found nothing does anyone have an idea.