Question about 2003 Chevrolet Silverado 2500HD

4 Answers

2003 Chevy 2500HD 6.0l cranks but won't start. Can hear the fuel pump prime when the key is turned. Changed the crankshaft position sensor and still won't start.

My husband was driving it home and it suddenly died on him. It took a couple of tries but it restarted. He got about a third of a mile and it died again. Got it started, went about the same distance and it died again. This time when he tried to start it all it did was click. He said he waited a minute then tried again and it cranked and eventually started and he made it home. When the key is turned you can hear the fuel pump kick on. A friend of ours said that we are not getting spark and said to try replacing the crankshaft position sensor and we did and we are still getting the same result. The truck cranks but won't start. Please help!! This is our only vehicle right now and I am the only one working and my job is so far away and there isn't a bus route anywhere within 5 miles even. Because of this I had to call in sick.

Posted by on

4 Answers

  • Level 1:

    An expert who has achieved level 1.

    Hot-Shot:

    An expert who has answered 20 questions.

    Corporal:

    An expert that has over 10 points.

    Mayor:

    An expert whose answer got voted for 2 times.

  • Contributor
  • 57 Answers

Check for spark, if "NO" spark check ICM module under the coil packs to see if they are OK. If they check out, then check the camshaft position sensor. Because if it won't start but acts like it is out of time when cranking the engine, the cam sensor is bad.

Posted on Nov 17, 2014

  • Paula Gilliam Nov 19, 2014

    We finally figured it out .. And thank you for your help you were right on the money with the crankshaft position sensor. Once we replaced that we discovered that yes the fuel pump was working but not pumping enough pressure because it was dying. When it rain it pours .. Lol .. It is fixed and running now and again thank you!!

×

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    Hot-Shot:

    An expert who has answered 20 questions.

    Corporal:

    An expert that has over 10 points.

    Mayor:

    An expert whose answer got voted for 2 times.

  • Expert
  • 58 Answers

Is it tripping a coad it could the output sensor or the ox sensor you can spend a lot of money changing sensor or get it to a place that can hook up computer to it and tell u what it is

Posted on Nov 17, 2014

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    MVP:

    An expert that got 5 achievements.

    Governor:

    An expert whose answer got voted for 20 times.

    Hot-Shot:

    An expert who has answered 20 questions.

  • Expert
  • 107 Answers

EGR can do this too. Typically yes a code would be present. Wal-Mart sells a cheap scan tool for $100. It only pulls codes and basic data. Many sensors under the hood can make this difficult. All above comments apply! Start with one and work your way through.

Posted on Nov 22, 2014

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Master:

    An expert who has achieved Level 3.

  • Master
  • 602 Answers

Sometimes a transponder will not recognise the ignition key chip usually the other key will work when you have two. I know this is a long shot not likely to be of help

Posted on Nov 17, 2014

6 Suggested Answers

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

  • 239 Answers

SOURCE: vehicle just keeps cranking wont start.

Make sure that your fuel presure is up to at least 60 psi if not that could be your problem. If not, make sure you are getting spark, if not could be your Crank sensor or ingniton module ECM. Usually if your Engine control module wouldn't be bad because of your fuel pump is working, but may not be putting out the proper pressure for the fuel system. Fuel Pumps are a Problem with that year..

Posted on Jun 10, 2008

  • 1 Answer

SOURCE: 2000 chevy blazer, truck cranks

Does your battery go dead?

Posted on Dec 18, 2008

Molson02536
  • 3854 Answers

SOURCE: 1992 Suburban 1500 with 5.7. Cranks but no spark.

Did you try to get any DTC codes from the ECM. If not here is the procedure to retrieving the DTC codes. http://www.troublecodes.net/GM/ Check the fuses, make sure there all good. hope you find a DTC code which would help us find out what is wrong with the suburban quicker. Keep me posted and good luck, be glad to help you.

Posted on Jun 04, 2009

  • 255 Answers

SOURCE: 1987 Chevy R10 project truck won't start

check the float on the carb is stuck shut not letting fuel in

Posted on Aug 17, 2009

blueextc3221
  • 15935 Answers

SOURCE: 2001 Chevy Malibu, 89,000 miles, 3.1 engine, won't start

CLICK HERE for the injector schematic.
CLICK HERE for the Ignition schematic.

Since the PCM uses info gatheres from the crank and cam sensors to calculate ignition - and there are no OBD codes - in all likelihood, the PCM itself is bad.

The Ignition Module, also transmits to the PCM.

It appears after all your testing - that the PCM is at fault.

It does not error report on itself (unfortunately).

The ignition timing is controlled by the Powertrain Control Module (PCM). No adjustment is necessary (distributorless ignition) or possible.

Please see the following....

The ignition timing is controlled by the Powertrain Control Module (PCM). No adjustment is necessary or possible.
The engines covered by this manual are equipped with distributorless ignitions, ignition timing is controlled by the Powertrain Control Module (PCM), as applicable. No adjustments are possible. If ignition timing is not within specification, there is a fault in the engine control system. Diagnose and repair the problem as necessary.
Ignition timing is the measurement, in degrees of crankshaft rotation, of the point at which the spark plugs fire in each of the cylinders. It is measured in degrees before or after Top Dead Center (TDC) of the compression stroke.
Ideally, the air/fuel mixture in the cylinder will be ignited by the spark plug just as the piston passes TDC of the compression stroke. If this happens, the piston will be at the beginning of the power stroke just as the compressed and ignited air/fuel mixture forces the piston down and turns the crankshaft. Because it takes a fraction of a second for the spark plug to ignite the mixture in the cylinder, the spark plug must fire a little before the piston reaches TDC. Otherwise, the mixture will not be completely ignited as the piston passes TDC and the full power of the explosion will not be used by the engine.
The timing measurement is given in degrees of crankshaft rotation before the piston reaches TDC (BTDC). If the setting for the ignition timing is 10 BTDC, each spark plug must fire 10 degrees before each piston reaches TDC. This only holds true, however, when the engine is at idle speed. The combustion process must be complete by 23° ATDC to maintain proper engine performance, fuel mileage, and low emissions.
As the engine speed increases, the pistons go faster. The spark plugs have to ignite the fuel even sooner if it is to be completely ignited when the piston reaches TDC. Spark timing changes are accomplished electronically by the engine and ignition control computers.
If the ignition is set too far advanced (BTDC), the ignition and expansion of the fuel in the cylinder will occur too soon and tend to force the piston down while it is still traveling up. This causes pre ignition or -knocking and pinging-. If the ignition spark is set too far retarded, or after TDC (ATDC), the piston will have already started on its way down when the fuel is ignited. The piston will be forced down for only a portion of its travel, resulting in poor engine performance and lack of power.
Timing marks or scales can be found on the rim of the crankshaft pulley and the timing cover. The marks on the pulley correspond to the position of the piston in the No. 1 cylinder. A stroboscopic (dynamic) timing light is hooked onto the No. 1 cylinder spark plug wire (2.2L engine only, on the 2.4L engines, special adapters are needed) . Every time the spark plug fires, the timing light flashes. By aiming the light at the timing marks while the engine is running, the exact position of the piston within the cylinder can be easily read (the flash of light makes the mark on the pulley appear to be standing still). Proper timing is indicated when the mark and scale are in specified alignment.


WARNING When checking timing with the engine running, take care not to get the timing light wires tangled in the fan blades and/or drive belts.

The engines covered by this manual are equipped with distributorless ignitions, ignition timing is controlled by the Powertrain Control Module (PCM), as applicable. No adjustments are possible. If ignition timing is not within specification, there is a fault in the engine control system. Diagnose and repair the problem as necessary.




Thanks for using FixYa!!

Posted on Aug 18, 2009

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Emergency fuel shut off


There is no emergency shutoff for the fuel pump. It is controlled from the ECM. There is a fuel pump relay in the relay/fuse box under the hood. But if you have power to the pump, it is probably ok. Having had a 1999 Dakota I had a situation where I was having intermittent shutdowns when driving that became more and more frequent. Sometimes I could restart immediately, other times I had to wait from 10-30 minutes before I could get a restart. I assumed a faulty fuel pump and replaced it only to find that it did not solve my problem. I researched the issue and found that the Dakotas and Durangos have a tendency to have faulty crankshaft position sensors. It will mimic a fuel pump issue since when the ECM loses sensor input, it shuts off the fuel pump. Test the pump this way - in a quiet setting, turn the key to the ON position, but do not crank the engine. With the drivers door open listen for a 2-3 second humming sound from the rear of the truck. This is the fuel pump priming the system to get fuel rail pressure. What then happens is once you start cranking and the engine fires, the ECM turns the pump on full-time. If the crank sensor is bad, the ECM cannot see that the engine is turning over and does not generate spark or fuel injector pulses, so even the fuel pump prime works, if it worked won't start the engine. At least if you hear the prime, you'll know the pump is functioning.

Sep 08, 2014 | 1999 Dodge Dakota

1 Answer

1997 cougar xr7 won't start?


Leaving the key on longer then two seconds does nothing ! When you first turn the key to on the PCM - engine computer will energize the fuel pump relay for 2 seconds ! If you want to turn the pump on for another 2 seconds you would need to turn the key off an then on again ! The only other way the PCM will energize the pump is while cranking the engine , if it sees an input from the crankshaft position sensor . Rather then just replace parts an making part stores rich , why not learn how to do proper diagnostics . Test the electrical circuits . What's the fuel pressure ? What does the mass air flow signal to the PCM look like ? Hooking up a scan tool an viewing engine sensor data etc.... Check the CCRM - constant control relay module . Google CCRM

Jun 01, 2017 | 1997 Mercury Cougar XR7

1 Answer

2003 s10 blazer cranks no start . when I was trying to test the crank sensor signal wire I found 10 volts present with ignition on not cranking. the ground wire has 12.5 with the key off and 12.21 volts...


Will a scan tool communicate with it or on the screen does it say NO COMM ! That's how you test a PCM/ECM . If no comm ,check power an ground's ,that's it .
Why were you messing with the crank sensor ? If the fuel pump primes for two seconds there is nothing wrong with it . When cranking the engine the PCM/ECM will only energize the fuel pump if it see's an input from the crank sensor ! You will not see 12 volts on the crank sensor signal return wire ! Crankshaft Position (CKP) Sensor
The CKP sensor is a three wire sensor based on the magneto resistive principle. A magneto resistive sensor uses two magnetic pickups between a permanent magnet. As an element such as a reluctor wheel passes the magnets the resulting change in the magnetic field is used by the sensor electronics to produce a digital output pulse. The PCM supplies a 12-volt, low reference, and signal circuit to the CKP sensor. The sensor returns a digital ON/OFF pulse 3 times per crankshaft revolution for the V6 engine, 4 times for the V8 engine. The CKP sensor reads the crankshaft mounted reluctor wheel to identify pairs of cylinders at top dead center (TDC).

May 20, 2017 | 2003 Chevrolet Blazer

1 Answer

2002 chevy malibu cranks but wont start


you should check the battery, if it is all right, you should try to check the starter and ignition.
_____________
Launch X431

Jun 17, 2013 | Cars & Trucks

1 Answer

No spark and no sound from pump


as you suggested crank position sensor cause such troubles, as hard starts and sometimes stalling. simply replace it.

Dec 05, 2011 | 2002 Chevrolet Blazer

1 Answer

Can you tell me where the crankshaft sensor is located? Would this being bad make it not start sometimes? Sometimes it will start up, other times, not. Sounds like the fuel pump is not running when it...


the crank sensor is behind the crank pulley and must pull off the pulley to gain access to it and it must have the air gap set so the timing slots don`t hit it when the motor is running,this can cause your problem also if the wires rub through by the crank pulley can cause it as well.you say you don`t hear the fuel pump running when it won`t start then you need to make sure that is what is happening as this will cause an intermittent no start(pump works sometimes).do you get a 2 second run pump prime when the key is turned on and a no start then it could be the crank sensor as the computer looks for a crank signal from the crank sensor when trying to start the car.

May 03, 2011 | 2001 Pontiac Grand Am SE

2 Answers

98 chevy cavalier cranks but wont start changed fuel pump,computer,crank shaft position sensor and the theft system light is staying on


try to start the car, than the anti theift would shut the car off. you wait ten min with the key on, until you see the anti theift flash or disapear. than turn key to off position and try to start it. this will reprogram the computer.. Good luck.

you can also try disconnecting the battery for 30 minutes

Oct 07, 2009 | 1998 Chevrolet Cavalier

2 Answers

I have a 2003 chevy express with the 4.3 v6/auto


fuel pressure regulator, or the computer needs reset!!

Sep 05, 2009 | 2003 Chevrolet Express

4 Answers

1998 Jeep Cherokee - hard to start


My 98 Cherokee was the exact same. I used to have to turn the key back and forth 3 times and then it would start. Otherwise it would just crank and crank for a while and then start. Pretty embarrassing! Took it to the dealer and they said that my fuel pump was losing pressure. I changed the fuel pump and I don't have to prime the pump anymore.

Feb 05, 2009 | 1998 Jeep Cherokee

Not finding what you are looking for?
Cars & Trucks Logo

348 people viewed this question

Ask a Question

Usually answered in minutes!

Top Chevrolet Experts

yadayada
yadayada

Level 3 Expert

75807 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22133 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

8172 Answers

Are you a Chevrolet Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...