Mechanics

CHEVY WONT START & NO CODES!

2000 Chevrolet Blazer

Engine Mechanical problem
2000 Chevy Blazer 6 cyl Four Wheel Drive Automatic 145000 miles

I have a 2000 Blazer 4.3 Liter Vortex. It was running great, then for no reason and with no lights coming on and no strange noises it just shut off and we haven't been able to start it since, unless we put fuel in the throttle body, then it will start and run for just a sec until the gas burns out. We have changed the fuel pump, fuel filter, fuel pressure regulator, camshaft positioning sensor, distributor cap & rotor and still it won't start. We scanned it and there are no codes coming up. Please help, I can't afford to put it in the shop and I hate to just keep wasting money on parts we don't need !
Thanks,
Rachel
Avatar
Birdmomma
May 6, 2010.



Did you check for power at the fuel pump? When you turn the key to on, the pump should run for 2-3 seconds, does it? If not, check fuses under the hood and in the cab, also check the fuel pump relay, it should be in the fuse box under the hood, but I will look it up later and get back to you.

Merlin2021
May 7, 2010.
All fuses amd relays have been tested and my new fuel pump is working great withy 60-66 psi, but still wont start.

Tiny
Birdmomma
May 7, 2010.
We checked it again this morning and we did get a code this time. P1351, so I got a new ignition coil & ignition control module but these didn't change a thing either. Please help I am tired of running to the parts store!

Tiny
Birdmomma
May 7, 2010.
DTC P1351: IGNITION CONTROL CIRCUIT - HIGH VOLTAGE Circuit Description Crankshaft Position (CKP) sensor provides VCM with reference pulse input. VCM uses CKP input to determine ignition spark timing for each cylinder. Once VCM calculates ignition timing, it sends a signal to ignition coil module on IC circuit. DTC will set when IC voltage is greater than 4.9 volts. Diagnostic Procedures 1. Perform On-Board Diagnostic (OBD) system check. See ON-BOARD DIAGNOSTIC SYSTEM CHECK. After performing OBD system check, go to next step. 2. Clear DTCs. Disconnect fuel injector connector. Crank engine for 15 seconds. Read DTCs. If this DTC resets, go to next step. If this DTC does not reset, see DIAGNOSTIC AIDS. 3. Turn ignition off. Reconnect fuel injector connector. Disconnect ignition coil module connector. Using DVOM in AC scale, check voltage between engine ground and IC control circuit at ignition coil module, while cranking engine. If voltage reading is 1-4 volts, go to step 9. If voltage reading is not 1-4 volts, go to next step. 4. Turn ignition off. Disconnect VCM harness connector. Check for open in IC control circuit between VCM harness connector terminal No. 9 and ignition coil module harness connector terminal " B". If circuit is open, go to next step. If resistance is not open, go to step 6. 5. Repair open IC control circuit between VCM and ignition coil module. After repairs, go to step 17. 6. Reconnect VCM harness connector. Turn ignition on, with engine off. Check voltage between ground and ignition control module harness connector terminal " B". If voltage reading is greater than one volt, go to next step. If voltage reading is not greater than one volt, go to step 8. 7. Repair short to voltage in IC control circuit between VCM and ignition control module. After repairs, go to step 17. 8. Check for poor VCM harness connections. If connections are faulty, go to step 15. If connections are okay, go to step 16. 9. Turn ignition off. Connect a test light between battery voltage and ignition coil module harness connector ground circuit. If test light illuminates, go to step 11. If test light does not illuminate, go to next step. 10. Repair open ignition coil module ground circuit. After repairs, go to step 17. 11. Turn ignition on. Connect test light between engine ground and ignition coil module harness connector ignition feed circuit, and then ignition coil module harness connector tachometer signal circuit. If test light illuminates on both circuits, go to step 13. If test light does not illuminate on both circuits, go to next step. 12. Repair faulty circuit. After repairs, go to step 17. 13. Check for poor connection at ignition coil module. If connection is faulty, go to step 15. If connection is okay, go to next step. NOTE: For circuit reference, see WIRING DIAGRAMS article. 14. Replace ignition coil module. After replacing module, go to step 16. 15. Repair faulty connection. After repairs, go to next step. 16. Replace VCM. Program replacement VCM using required equipment. After replacing VCM, go to next step. 17. Using scan tool, select DTC, CLEAR INFO function. Start engine and allow it to reach operating temperature. Using scan tool, select DTC, SPECIFIC function and enter this DTC. Operate vehicle within conditions required to set DTC. If scan tool indicates that this test RAN AND PASSED, go to next step. If scan tool does not indicate that this test RAN AND PASSED, repeat step 2. 18. Using scan tool, select Read and Record INFO, REVIEW INFO function. Check if any undiagnosed DTCs are displayed. Diagnose affected DTCs. If no additional DTCs are displayed, system is okay. Diagnostic Aids Check for faulty connections or damaged harness. If connections and harness appear okay, observe scan tool while moving all related harnesses and connectors. A change in scan tool display indicates fault location.
5/7/2010 .
Check email for wiring diagram.

Merlin2021
May 7, 2010.
Hi Mike,
Thanks for your replys to my 2000 Blazer problems. I hate to bother you but can you tell me where the fuel injector connector is located and what it looks like? And do you happen to have a diagram of the 4.3L Vortex motor that my blazer has?
Thanks again for your help, I will let you when we find out what the problem is.

Tiny
Birdmomma
May 7, 2010.
In your case a V6 has six injectors, with a connector at each one, and a main harness connector usually at the back end of the motor. Injector circuit is tested as follows: INJECTOR CIRCUIT DIAGNOSIS 4.3L, 5.0L, 5.7L & 7.4L 1. Perform OBD system check. See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in appropriate SELF-DIAGNOSTICS article. After performing OBD system check, go to next step. 2. Disconnect injector harness connector at intake manifold. Turn ignition on. Using test light connected to ground, probe injector ignition feed circuits. If test light illuminates at all injector feed circuits, go to step 6. If test light does not illuminate at all injector feed circuits, go to next step. 3. If test light illuminates for only some of the injector circuits, go to step 5. If test light does not illuminate for any injector circuit, go to next step. 4. Check ECM I fuse (20-amp), located in underhood fuse block. If fuse is open, go to step 10. If fuse is okay, go to step 11. 5. Check for open in faulty injector feed circuit. After locating faulty circuit, go to step 12. 6. Install injector test light to each injector circuit, one at a time. Crank engine. If injector test light flashes for each injector, check fuel injector(s). See FUEL SYSTEM in appropriate SYSTEM & COMPONENT TESTING article. If injector test light does not flash for each injector circuit, go to next step. 7. If injector test light was on steady for any injector circuit, go to next step. If injector test light did not illuminate for any injector circuit, go to step 9. 8. Install injector test light on faulty injector circuit. Turn ignition off. Disconnect VCM harness connector (Red). Turn ignition on. If injector test light is off, go to step 16. If injector test light remains illuminated, go to step 13. 9. Check for open or short to voltage in injector control circuit. If circuit is open or shorted, go to step 12. If circuit is okay, go to step 14. 10. Check for short to ground in injector control circuit. After locating short, go to step 12. 11. Repair open or short to ground on all injector feed circuits. After repairs, go to step 17. 12. Repair circuit as necessary. After repairs, go to step 17. 13. Repair short to ground in injector control circuit. After repairs, go to step 17. 14. Check terminal contact at VCM harness connector. If terminal contact is faulty, go to next step. If terminal contact is okay, go to step 16. 15. Repair terminal contact as necessary. After repairs, go to step 17. 16. Replace VCM. Perform VCM reprogramming procedures. After repairs, go to next step. 17. Using scan tool, select DTC, CLEAR INFO function. Attempt to start engine. If engine starts and continues to run, go to next step. If engine does not start, or starts and stalls, go to step 2. 18. Allow engine to reach normal operating temperature. Using scan tool, select DTC, FAILED THIS IGN function. If any other DTCs are set, diagnose DTCs. See appropriate SELF- DIAGNOSTICS article. If no other DTCs are set, go to next step. 19. Using scan tool, select CAPTURE INFO, REVIEW INFO function. If additional undiagnosed DTCs are set, diagnose DTCs. See appropriate SELF-DIAGNOSTICS article. If additional NOTE: This test applies to vehicles equipped with VCM. DTCs are not present, system is okay. Page 2 of 2 5/8/2010 .
Couldnt find a picture, sorry.

Merlin2021
May 8, 2010.