Skip the auto shop - Our mechanics make house calls

Q: New motor, ran good one week but now will not start. Changed multiple sensors. It will try and start with the throttle body wide open

asked by on

Has fire, fuel, and compression, cam and crank sensors replaced. If throttle body is held open it will almost crank then die. Confirmed 50 psi from pump and all injectors are spraying fuel. Please offer any advice? 2002 Dodge Ram 1500, 3.7 liter v6

My car has 170000 miles.
My car has an automatic transmission.

Hi there. The first thing you could do is check all fuses. On some vehicles, for example, the fuse to the power door lock provides power to a module that initiates a "start" signal to the PCM. Although you do report that it ran fine for a week, you may want to consider the age of the gas in the tank. If it is older than two months, drain the tank and use fresh fuel. Old fuel will not start an engine at times.

Opening the throttle plate, and thus introducing more air and it then getting "closer" to starting, insinuates a possible air-fuel ratio problem, potentially too much fuel. Are the plugs wet? Does the Check Engine Light come on when the key is in the "On" position (thus signifying PCM is on line and in diagnostic mode)? If so, what are the trouble codes set?

It is possible the car’s Engine Immobilizer (security system) is locked out. Try disconnecting negative terminal from battery for 10 minutes and re-connecting for a reset. If your car is equipped with a transponder key, try a different, known working key. If none of this works or you need further help, I recommend having a qualified professional, like one from YourMechanic, diagnose and repair the starting issue.

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
  • Home
  • Questions
  • New motor, ran good one week but now will not start. Changed multiple sensors. It will try and start with the throttle body wide open

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Axle boot

You would need to have the axle replaced or the boot replaced if there is no joint damage. The joint will get damaged from dirt and debris getting in it when the boot is torn. The labor to replace the...

Q: My dealer told me that I should replace the oil pump along with the timing belt

Hi There, There are a number of differences between the oil pump and the water pump, however the main difference is that the water pump pumps the coolant through the motor and is driven by the timing belt and the...

Q: Porsche Cayenne S 2005 has code P0349 read on scanner.

Hi there. The Camshaft Position Sensor tone ring could be damaged or there could be an electrical problem with the electrical circuit with the camshaft position sensor harness. I recommend replacing the camshaft position sensor. If you need further assistance...

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...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...