s10 v6 cranking, firing and has spark but will not start? what could it be

IF it cranks Like a Bear, and your getting spark! "Pull plug wire off,put screw driver thru plug ring,have someone cranck it over while touching the block,or a bracket, and should see spark" If you see spark, My un- Educated guess would be Timing Belt or chain, Good Luck,

fuel pressure test. 4.3 vortec is know for failed pressure reg and fuel pumps. Should be between 55 and 65

Could be a bad distributor cap from moisture (if it is the flat type). My Blazer had fuel and spark but would not start. It was cranking very weird. What I mean was it would crank for three seconds then all the lights would go dead like the motor was locking up then it would crank for another three seconds. I poured gas into the intake, no help. I then pulled #1 spark plug and cranked it and it was getting spark? Weird, so I thought I had a major timing issue. My buddy recommend changing the cap as the 4.3, 5.7 Vortecs with the flat type caps are notorious for building up moisture in the cap. Changed the cap and wholla... fired right up. Also got a bonus by the check engine light that I has for years was extunguished... crazy but very happy!

I agree. sounds like a timing issue,

1996 Chevy s10 will not start

4.3 have spark fuel pressure but not starting

Hello guys. I have problems with my 1994 Chevy s10 blazer. when I put the key in and turn it will NOT start right up. it will crank but not start. what can the issue be

when it doesn't start, you need to test fuel injectors for 12 volts and a pulse

What about the ECM module. They fail often in Chevy's and it is that module that sends the signal to the fuel injectors to tell them to fire. This may be the case particularly if the spark plugs are bone dry after several unsuccessful attempts to start the engine.

I have a 1996 cheb s10 4.3L v6 vortex, I change spark, wires,distributor, rotor button, fuel filter, crank sensor, cam sensor, when I tried to drive it. It would sputter and it will not accelerate, just more sputtering.

I'm by no means an expert but Sounds like fuel pump to me.. The same thing happen to me in my van and I changed the fuel pump and it fixed it..

Yeah I had a Blazer that did that, changed O2 sensor, fuel pump, sensor, and filter.It would drive ok for awhile then just spudder, Made it all the way from KY to MIch. one time and it broke down on the way back. Well ended up being a cracked injector and cost me $600,00. I hope it's something more simple for you.

On my S-10 I replaced ignition module, coil,cam sensor, crank sensor without success in starting engine, I then replaced cap & rotor button that looked good, my engine started like new, verify that distributor cap is tightly mounted as some new caps come with screws that are to long & though they are tight, cap is not tightly mounted.

I have a 2000 S10 that will not start change the fuel pump it will not start but fires the gas is not coming out of the line it don't go through the filter and we bought a new one and still have the same problem what can be wrong

Just did head gaskets got it all back together. timings and fuel are good.still not starting..anyone with any ideas thanks

I have a 01 S10 pickup 4.3 it's wanting to start but it isn't I check the fuel pump that's working I check the fuel pressure that's working fuel filter changed I'm wondering if it's the timing or something I don't know but I can't figure it out but I have any answers

I have a 01 S10 pickup fuel pump has been checked fuel filters been changed it wants to start but it isn't comments answers for me thank you

Sounds like the ignition control module under the distributor. It commands the fuel injectors to fire.

I have a 1998 2.2l doing the same thing ill be working on it today if i get it going i will let ypu know exactly what i did

My 1995 S10, 4.3 was running rough so I replaced the cap and rotor, which were well beyond worn. Also replaced plugs and wires, which showed normal wear. Now it will crank like a champ but doesn't start. Getting spark all the way to the plugs, but it doesn't even try. Getting plenty of gas, and it was running just before I started working on it. I put the old cap and rotor back on with no luck.

I have a Chevy 98 S10 2.2 Vortec already change the spark plugs the starter the alternator the battery the spark plugs already but it won't start no crank to start it them i just turr the keys and the starter woeks good is all new but the motor doesn't want like crank what could be the problem

I ended up replacing the ICM to no avail. Then i replaced the ERG valve, which was dirty to the point of not moving, and cleaning it didn't help. New ERG, problem fixed.

I have a 2002 s10 4.3 vortec ..it has problems cranking in the morning time but after ot runs it cranks fine..

What could be wrong

I have a 2001 blazer when you turn on key fuel pressure goes up to 60psi and when you start it goes to 63 psi when you turn it off fuel pressure dropped fast to 0psi

I don't no but I have a 99 blazer put.a new motor in it it ran in the s10 they took it out of I put it in the blazer an even put a new starter on it I turn the key on all lights come on but when you go to start it nothing what could it be wrong anybody

My 88 has spark, fuel and air! I've changed everything but the distributor? Could that be the issue, incorrect spark and fuel distribution?

Ive had this same no start multiple times.the fuse box has gotten crispy where all the terminals for fuses are. I had to reroute multiple wires to independent fuse holder because of bad factory fuse box. Start with multimeter with key in on position and check that the fuse box wires actually get power from the fuses. Result of cheaply made fuse box all the connectors falling apart. The no start began with a cracked distributor. Another cheaply made factory item. Horrid flaws in casting make it break in half under load from cam shaft. Replaced it with a lifetime one from autozone an fixxed for awile. Then had a light intake gasket leak moisture in oil. So replaced gasket an hasnt ran right since. Been over everything a hundred times. Well today it cranks random plugs fire but no start. Puking gas thru exhaust but throttle plate has clean mist spray from injectors. Im thinking distributor cracked again or jumped timing chain or ignition component bad. At this point i think a stick of dynomite is the only logical solution

check for pluged cat converter remove up streem o2 sensor and see if starts

OK, here is my Solution to rebuilding the 4.3 vortec only to have no start and misfire conditions. Step 1: follow the instructions with an open mind.... They are mostly right and a great guide. Step 2: forget any other motor than the vortec motor while working on it. Step 3: LOOK AT PICTURES OF NEW PARTS. STEP 4: LOOK AT YOUR PARTS NEXT TO THE PICTURES My 0 mile rebuild sounded like a 21 gun salute the first time it started. I thought the ECU may have needed to reset for the new sensors. NOPE.... Redid the timing chain over and over making sure everything lined up perfectly by the marks.... Fail.... after 2 months of forum reading, readjusting, failure, frustration, way too may new parts to replace new parts, I found my harmonic balancer had shifted. the marks were about 90 degrees off. So I brought the #1 piston to top dead center (again). this time I made sure both valves were closed, marked the balancer on the timing mark at the timing cover. installed the distributor dead on. Rotated the motor 720 degrees to verify everything continued to line up. I put the truck back together and...... NOTHING.... I only found this in one forum, nowhere else, not in a manual, not on GMs technician data, not on alldataDIY, just a forum. after verifying everything lines up, ROTATE THE CRANKSHAFT 360 DEGREES AND REINSTALL THE DISTRIBUTOR. Finally, the truck runs without backfiring, Idling extremely high (2400 RPM idle) or blowing apart Mass Airflow Sensors.

Well engine is done finally got it to start only to discover passenger rear cylinder had detonated so hard it blew a hole thru side of the block in compression area of cylinder wall. I suspect the new distributor failed again. Have a 4.3liter L99 vented optispark v8 aka baby LT1. I wonder if it would bolt to transmission in early alum intake 4.3 liter v6? Anyone ever tried this? I know engine mounts diff and need ecm with Lt but does transmission mount up the same?

The one I have doesn't use a cat or 02 an egr removed. Basically set up with min stuff to go wrong but there's one item can't get decent part so I'm done with 4.3 v6. Brand new life time warranty auto zone distributor flops around in its housing bad bearings. Detonated an blew hole in block. To bad really liked the torque of first gen 4.3 v6 but that's a flaw I'm done dealing with.

Chuck, sounds like you shot yourself in the foot a little here. You deleted egr on an engine that is known to have ping (detonation) problems. Egr directly combats engine ping. Sorry you had issues but I'd hardly call the distributor a weak link in a 4.3

I have a 2000 Chevy blazer have put a new timing chain new crank sensor new distributor new distributor cap new button new computer and a new battery and it still won't start any helpful suggestions on what it could be

So if I have fuel at the rail, spark compression test done and all great, why after putting new pump in will it not start.before I changed the pump it would need primed but afterwards it would start fine. Then changed it the truck is same but worse. Now my pump wires where cut after putting new pump in and shorted out the relay on (ecm) now does that mean my relay to my fuel pump relay is fired should I change that?, ok now when primed now with new pump the truck runs when I give it gas it dies out, but will die once prime is gone. What's your opionon on this? Please anyone!

I have a 90 Chevy getting fire and gas to throttle body just won't spray at all what do I do

The pickup in the distributor is used to fire the injectors

Coil and ignition module. Reason is may have spark but if not bright blue it's not enough to start so fuel is pumping and clouding and running into oil. This just solved my problem

Okay fellars, i have stumbled upon some news for you..... I have a 95GMC Safari 4.3 cpi fuel injection. They use a second fuel injection pump that sits under the upper intake.... what a genius invention General Motors came up with, NOT... so stupid, why could they not have come up with the same idea every othet manufacturer has ??? Unfortunately it took them awhile, but they finally realized using external injectors is better. Unfortunately this particular fuel injection system was used for a few years.... this motor has a second fuel pump that sits under the upper intake, and is sometimes referred to as a "spider pump".... within this so called spider pump is a miniature ECM that tells each injector when to supply fuel. If you have a 4.3 that is backfiring through the tailpipe, and intake as well, your exhaust is heating up, your muffler has torn apart from backfiring, You may want to invest with a spider pump. Otherwise known as a CPI fuel injection pump. This second fuel pump not only pumps fuel Into the injectors, but it also keeps them in the right timing. Generally they start out and about $250. You will also need upper intake Gaskets. Also don't forget you will need to remove the distributor before removing the intake. But be reminded, be sure to check all other ignition problems first.

I have a 1994 chevy s 10 4x4 4.3. I am having a problem it starts great and it runs great. When it gets warm around 10 miles it starts to shut down and then it shuts off. It takes about 15 min. To get it started again...

Dont forget about the fuel cutoff switch , tank selector valve ,, and the sending unit switch , as well as the oil pressure sensor these things can also cause one to no start issues

Ive got a 94 4x4 5speed 4.3 had to do a motor swap and I accidently broke the oil pressure switch and I can't get it to start now till I replace the switch unless you can bypass if anyone knows how to bypass please let me know

I have a question I have a 89 Chevy van with a 4.3 and I'm backfiring from the carb and it won't start iv done plugs wires cap and rotorbutton but still have the problem also new fuel pump and filter

li have a 1988 s10 4 banger decided to leave some marks on the concrete and she spits and stutters and now wont start i need help gmail.me at phillip11perry@gmail.com if you have any tips thanks

All you guys with 4.3 vortecs that are getting fuel and spark but cant get them to run take your cap off and turn it upside down trace the spark from where number 1 is marked on the cap all the way to the other side where it actually fires it's about 180 degrees the other way. If your rotor is not pointing there when number 1 is at tdc then you need to retime it so it is and you also have to be within 4 degrees or computer cant adjust. You're welcome lol

I’ve got a 96 gmc Sonoma high rider it’s basically a ZR 2 I built it two years ago I put a 2000 front clip doors and bed is step side painted hugger orange it was missing the other day I stopped at the jip joint also known as (autozone) the said it had a p0302 code misfire well I changed the spider unit I had my girlfriend come out and crank it over for me and all the injectors sprayed gas like there supposed to well put it back together no start now I re gaped the plugs this morning and now it will crank a couple times and stop I’m getting spark to all plugs and it's flooded after I crank it... the plugs are soaked and blew gas out of cylinders I put plug in wire and held it to exhaust gf cranked over got spark to plug...

I have a 2005 Silverado 1500 with a 4.3 Vortec. After 200.000 miles and many years of unexpected, just when you least expect it, I always carry a "Rescue Kit". It has a GM Coil, GM Module, Marine Distributor Cap and Rotor, and two GM Coil Wires. Total Cost $200.00 and I have NEVER been unable to be on my way in less than 15 minutes. ***The Coil Wire is usually the problem !!