Skip the auto shop - Our mechanics make house calls

Q: Truck not starting - 2002 Chevrolet Trailblazer

asked by on

Well it cut off on me while driving to get gas cause it was on empty so we relaced the fuel pump cause it wouldn't start but it wouldn't start after the fuel pump replacement but you can hear the pump come on and like I said the fuel filter is good and the gas is flowing thru the lines but it still won't start but the battery is weak can that have something to do with it not starting and also the computer had have me a code for the cam sensor and that has been replaced but still it won't start so what can it be cause I really need my truck it's my only transportation and I don't have money for high fixes

My car has 211125 miles.
My car has an automatic transmission.

A: Hi there, thanks for writing in about your ...

Hi there, thanks for writing in about your 1992 Dodge Spirit. A slow cranking motor can definitely impede a motor from starting. First thing you need to do is connect a battery charger and get the cranking speed up. As for any other problems you might have, I wouldn't make any assumptions. I recommend you check for spark, fuel, and injector pulse. Depending on what is missing will decide which diagnostic path to follow.

Spark problems will be coils, PCM, or a power supply issue.

Fuel pressure should be checked with a fuel pressure gauge. Your fuel pressure specification should be 48-52 psi with the key on. If you have released the fuel pressure at sometime, you may need to cycle the key once or twice to build the appropriate amount of pressure. If the pump is running, and it is new, you should have good fuel pressure.

You will need a noid light to check or injector pulse. A noid light is plugged into the injector connector in place of a single injector. Crank the motor and the noid light should flashed rapidly. You stated you had a cam sensor code. A cam sensor and a cranks sensor can cause the PCM not to fire the injectors and your noid light, or injector, will not fire. I would be checking these two sensors with the motor cranking using a scanner to watch the sensor waveforms.

Beyond the items stated above, your 4.2L motor has some camshaft chain issues as a result of bad chain tensioners. This can cause some strange driving issues and can often set cam sensor codes.

If you need help scoping this problem out, a certified technician from YourMechanic can come to your car's location to diagnose the starting issue and let you know what needs repair.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Its shutting off while driving

Your symptoms suggest that there is a short or other electrical current draw that is playing havoc with your electrical system. GM issued a recall (Recall 12V406000) for a problem with shorts in the door lock control module, overheating electrical...

Q: Car making squeaking and growling noise from under the hood by alternator

The shaking and stalling out as you describe can be caused by a variety of issues. When this happens there is likely a Check Engine Light on that should register a fault code in the car's computer. I would recommend...

Q: Car is vibrating when accelerating - 2003 Chevrolet Trailblazer

Hi there. There are several possibilities for the vibration and lack of power upon vehicle acceleration. The missing fuel cap should not affect drivability. Assuming the Check Engine Light has been on for the missing fuel cap, this leads me...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...