Q: Changed throttle body assembly, now it won't start

asked by on

I just brought 03 denali 6.0 died on way home pull over n seen battery cables were lose so tighten them it cranked further down the road it did it again wiggle wires that were lose so tighten them again it cranked.now I drove it it died again so I tap on throttle position sensor it cranked.so I replaced throttle body n now it won't start turns over ttys but nothing.check all fuses,wires,trace them down all good fuel pumps is coming on.put it on scanner no codes come up I think it ain't getting fuel so I just brought a fuel filter to see if that's it.so if you can give me something else to do I would love too no.

My car has 152789 miles.
My car has an automatic transmission.

Hi and thanks for contacting YourMechanic. The problem might be with the crankshaft position sensor being effected by heat. This can be verified by measuring the resistance of the crankshaft sensor with a digital volt ohm meter (DVOM) and then heat the sensor with a heat gun to see if the sensor resistance reading goes out of spec.

If the crankshaft sensor is reading normal, then the ignition switch may have a burned contact or has corrosion. If you need further assistance troubleshooting your vehicle, then seek out a technician, such as one from YourMechanic, that can pinpoint the cause of the starting problem.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Changed throttle body assembly, now it won't start

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: My Yukon 04 has been reading engine reduced power for about a month now. I put a brand new throttle body and throttle pedal positi

Hi Jay. Thanks for contacting us today. The problem with reduced engine power indication lights is that diagnosing the root issue can take a tremendous amount of trial and error or more importantly, detailed inspections to determine the source. The...

Q: whining noise front of engine, EVAP and temperature control

Hello, thank you for writing in. The first two symptoms may be related. Finding a leak in the EVAP system will take some time and focus. If the noise goes away after fixing the leak, then we know we can...

Q: Can a bad bearing mess up the brakes and rotors in the front?

If the wheel bearing is defective, that will not damage the brake rotor or the brake assembly. However, when installing the new bearing, the factory procedure must be carefully adhered to. In particular, the hub retaining nut has to be...

Related articles

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...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.