My 1995 blazer 4.3 cmfi 4x4 stalled in town i got it home and i think i have it narrowed down to a fuel problem. it will try to start if i spray starting fluid in butterfly, fuel pressure is 61 and 58 after ten min. it has new fuel pump,fuel filter,plugs,wires,cap and rotor. i also installed a screen on egr valve. it has been running great then stalled at redlight and hasent started since. help me , the next part i buy might be a hand grenade. pettytrucker

VIN , code "W" blazer.
1995 cars of any make are hard to keep going, this transitional year. (just before USA EPA OBD2 mandate)
4.3L v6 262cu-in , a 350-v8 engine with 2 cylinders cut off.
Your engine is the LB4 (1986 to 1995) then 1996 OBD2 laws kicked in (EFI huge changes)
1995 TBI engines were all balance shaft engines. 165HP
but.. what really is there needs to be learned first. see this.

VIN W, RPO L35:
Central Sequential Fuel Injection (CSFI), Sequential Fuel Injection (SFI). Manufactured from 1996 to 2003. This engine is similar to the VIN X, RPO LF6 except for increased hp and torque. The only likely difference is computer programming.
180hp, 245ft/lbs (2wd pickups), 190hp, 250ft/lbs (Blazers and 4x4s)
1995 VIN X and all 1996-99 4.3L engines-HVS distributor Firing order: 1-6-5-4-3-2 Distributor rotation: clockwise
Does the Distributor have vertical HV towers or horizontal HV terminals , they used both that year 1 works,other does not, based on CSFI or CMFI , changes MID YEAR new

DOES IT have TBI throttle body injector, or the MPI. 6 injectors.?
Be aware that on July1, 1995 , OBD2 engine were made for the 1996 year or even some 1995 -1/2 year too.
and very important to get this right or wrong spark parts will be bought.(the distributors and such)
1995-1/2 cars, are in fact very hard to find fitting parts and to diagnose,
It would be nice to see a photo of the top of the engine one can see the truth of all the above,.

Diagnosing it as it is: (when failed, only)

First is spark if engine passes a compression test, this old
when the engine cranks fast and does not start, it lost spark or lost air.
The IAC must work right to add error so it can start, or it floods. (so add 5% air with right foot, starts NOW?
We check spark on all 6 cylinders . or from the spark coil direct.
Spark timing must be kinda ok as it runs before.

is park looks good them, try test fuel ,spray , instant start in a can, sold in all autostores
spray it 3 seconds, in the air cleaner or to TB throttle body direct.
it will start and run for 3 seconds, and stall , repeat 3 times.
If no start add 5% air,with right foot to compensate for bad IAC valve stuck closed
also the EGR must never be open at cranked starts or at idle or engine will stall.


by now your fuel can be bad. or FPR bad, fuel pressure all wrong, we test that.
Test fuel tests, proves ,engine runs and sounds good. and can be done with Fuel pump fuse pulled too.

Fuel pressure dead
bad fuel
fuel pressure too high or too low.. PSI, spec,
IAC dead,means no air to start the engine, it must be good and free to do so, this air valve.
lacking startup air, means it floods.
if flooding now and spark tip soaked in fuel , use the WOT Unflood trick (method) of starting
floor the gas pedal, (this act cuts injections dead) and crack the engine clear the flood.

that is about it, until photos if the engine are show for CSFI, CMFI system is there or engine swaps worng
or wrong parts put there, like wrong distributor.

also the injectors may leak or be 1/2 clogged.
we do and injector balance test (MPI) to do that and the leak down test at the same time.
the MAP sensor too can be intermittent this old and is the key fueling right sensor. or its vacuum hose cracked ,kinked or clogged. The maf must work at all times. The ECU reads the MAP and injects basted off this BARO reading. (and RPM)


we know runs, but does not start, a times.
next time use the 5% air test, crank it and add 5% throttle. this hides bad IAC, valve.
the IAC can stick closed easy and idle and startup air can fail


more, bad FPR fuel pressure regulator
Intake Manifold Tuning Valve (IMTV)? stuck open (3500rpm is open time ,and not below)
the modulated EGR can leak too. and must not at idle or cranked
as you see there is lots to fail here.

if spark is the cause, new coil , no ICM , new distributors best old parts can be intermittent or fails only hot or cold. or at random failures.

for sure all part I mentioned above are all common failures. the test we do finds it.

Try doing the following.

Engine stalling issue at low speeds

This problem is commonly caused by a dirty automatic idle speed control valve and throttle valve. Buy a can of throttle valve cleaner from NAPA or Carquest (made by CRC chemicals) and spray it into the air intake while the engine is running, use up about 1/2 the can, engine will try to stall hold the speed up, shut it down and let it soak for 30 minutes, restart and blow out the remaining fluid, shut it down and disconnect the negative battery cable for 5 Min's to reset the base idle control

you

Replace coil

try checking air cleaner box to be sealed or dirty air filter and try to clean mass air flow sensor also check for dirty air intake only clean mass with special mass cleaner . also look for vac leaks and fuel pressure .

check the 2 wire molley plug going around the front of the intake down into the injector i have found many of those tend to overheat on the plug just cut it and splice the wires back togehter

I`m having the same problem with mine 4.3 vortec CMFI . I have narrowed it down to three things (i believe). #1 Fuel pressure regulator. #2 Power Train Control Module #3 Deep inside the injector ?-- Have to start taking engine apart from the top. Answer #1 40 dollars Answer #2 approx. 150 - 450 These two are parts only. Answer #3 How deep are your pockets? Remember if you Buy a PCM and connect it and it is not your problem you can not take it back.

Try to spray a shot of starting fluid in your air filter inlet. if it fires check fuel pump presure, And fuel pump relay.

There is no carb, either throttle body or fuel injection.If it was fuel related it would not cause all the lights to come on.Sounds like electrical and will have to be tracked down and diagnosed. Your computer may have gone out but that has to be diagnosed.

do you get check engine codes?..have you done a leak down test and compression test to determine mechanical engine health?