94 s-10 blazer hard to start but runs fine once running

Ive got a 94 s-10 blazer with a 4.3 Vortec CPI motor. Ive replaced the coil,cap, plugs, wires, fuel filter, injector, and tested the fuel pressure. Im getting 60 psi up to the intake. When it sets awhile it doesnt want to start. it acts like its not getting fuel or fire. if i spray starting fluid into it it will hit and if i do that enough times it will start and stay running. It runs like crap until it warms up, when it does it runs good. while its warming up it has no power and i have to floor board the gas pedal to get it to go when its in gear. and it chugs and knocks like a diesel motor when i do this. What else could possible be wrong with it? ive replaced over $600 worth of parts so far and it still does it. Someone please help.

check your timeing, could be off by just a little bit, also check for codes, stored, not neccisarily a check engin light now, but the code will be stored

thanks didnt think about the timing. The check engine light has never come on, so would there still be codes? and if so how do i get to them

could be, you need that little key that goes into i belve the dash, go to autozone, theyll know, tell them you need to see if you have any stored codes in your computer

One thing I don't see replaced is the ignition module, which sits inside your distributor. Just replaced mine as well as coil to stop similar problems. Mine would start, stall after warmed, and then would not start for a while. thought it fuel, but ignition was firing poorly and at times not at all. Just a thought.

Ive got a 94 s-10 blazer with a 4.3 Vortec CPI motor. Ive replaced the coil,cap, plugs, wires, fuel filter, injector, and tested the fuel pressure. Im getting 60 psi up to the intake. When it sets awhile it doesnt want to start. it acts like its not getting fuel or fire. if i spray starting fluid into it it will hit and if i do that enough times it will start and stay running. It runs like crap until it warms up, when it does it runs good. while its warming up it has no power and i have to floor board the gas pedal to get it to go when its in gear. and it chugs and knocks like a diesel motor when i do this. What else could possible be wrong with it? ive replaced over $600 worth of parts so far and it still does it. Someone please help.

Just my two cents here, From your description, it sounds as if it is fuel starved in start mode and when it warms up, you said it runs fine. The timing and the ignition module are good ideas but it sounds temperature related and I would first look to the ECT sensor. Just my opinion.

thanks for your suggestions. Its been to cold here lately to work on but hopefully this weekend itll get a little warmer. So keep the suggestions coming

Check for vaccume leaks at the carborators base, w/ starting fluid sprayed at it's base when running. You can hear the engine rev-up it you have a leak. It is comon for that gasket to seperate and start pulling air in. Some have a wire from it, that's to a heating element in the gasket, that cracks sometimes.....turn-up the idle speed some and make sure the choke is working.....my two bits....good luck!

Check for vaccume leaks at the carborators base, w/ starting fluid sprayed at it's base when running. You can hear the engine rev-up it you have a leak. It is comon for that gasket to seperate and start pulling air in. Some have a wire from it, that's to a heating element in the gasket, that cracks sometimes.....turn-up the idle speed some and make sure the choke is working.....my two bits....good luck!

Carburaetor? On a '94 Vortec?

sorry, about that....I'm messing with an '85 and that was the first thing the shop guy told me to check....and it didn't work....
good luck

Remove the top IMTV valve and check for washing in the upper plenum.

1 srt any code stored or showig? Service engine light on? If so see what codes and check components. Check fuel system again. With ignition on pump running Should have 58-64 psi fuel pressure then when pump shuts off pressure may drop several pounds then hold steady. if not then block pressure line by pinching flexible hose. After pump build pressure then shuts off. If it holds then you will need to pull the fuel pump and check fuel pulse dampener which is on the top of fuel pump and see if partially disconnected or seals are bad. If they are good then you fuel pump is leaking backcausing hard starting. If it doesn't hold after you pinch the pressure side off then pinch the return side off and see if it holds. if it doesn;t then it will be the cpi unit regulaor.But did you say that you had replaced it recently. If fuel system checks out then check for vacume leaks bad hoses ector maybe air plenum not torqued properly or bad upper intake gasket? If nothing then check the ignition system for chaffed wires connectors and check camshft sensor and crank sensor. Spark plugs gapped correct? Could be one of emmision sensors also but should have a code set for it. May this will help any way that's my thoughts.Good luck

1 srt any code stored or showig? Service engine light on? If so see what codes and check components. Check fuel system again. With ignition on pump running Should have 58-64 psi fuel pressure then when pump shuts off pressure may drop several pounds then hold steady. if not then block pressure line by pinching flexible hose. After pump build pressure then shuts off. If it holds then you will need to pull the fuel pump and check fuel pulse dampener which is on the top of fuel pump and see if partially disconnected or seals are bad. If they are good then you fuel pump is leaking backcausing hard starting. If it doesn't hold after you pinch the pressure side off then pinch the return side off and see if it holds. if it doesn;t then it will be the cpi unit regulaor.But did you say that you had replaced it recently. If fuel system checks out then check for vacume leaks bad hoses ector maybe air plenum not torqued properly or bad upper intake gasket? If nothing then check the ignition system for chaffed wires connectors and check camshft sensor and crank sensor. Spark plugs gapped correct? Could be one of emmision sensors also but should have a code set for it. May this will help any way that's my thoughts.Good luck

Don't believe the '94 has a fuel pump dampener or camshaft or crank sensors

thanks for all your help. i finally figured it out. the computer had a short in it. I had a buddy who owned his own shop and had one of those really expensive scan tools. It showed the injector was usually not getting a pulse or getting an erratic pulse. Replaced the computer and it runs fine. Thank god for scantools. thanks a bunch.