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Q: truck hesitates at 30 miles an hour what could be wrong. Could it be the timing chain

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Change the intake manifold, o2 sensors, cam and crank sensors. That car will not go passed 3000rpms and stutters at 30mph

My car has 225000 miles.
My car has an automatic transmission.

A: Hello and thank you for contacting YourMech...

Hello and thank you for contacting YourMechanic. Sounds like you have a fuel filter plug issue and a throttle position sensor issue making the engine starve for fuel and preventing the engine from accelerating (possibly in limp mode). Check the fuel pressure on the fuel rail and see if you get 35 psi or more. If you get less than 35 psi, then you would need to replace the fuel filter and clean the injectors. If you have 35 psi or more, then check the TPS for voltage and ground. If the harness has voltage and a ground, then back probe the wires with them hooked up to the sensor. Throttle the engine and see what the voltage does. If the voltage does nothing, then replace the sensor.

If the voltage changes, then the sensor is working and there is a possible timing chain problem. To determine the timing chain issue, grab a timing light and hook it up to the battery. Put the amp inductive pick up on the number 1 spark plug wire. Turn on the light with the engine running and see if the light is steady or moves around. If the light moves around, then the timing chain has stretched and needs replaced. If the light is steady, then the timing chain is okay. If everything checks out to be good, then there is an issue with your transmission's torque converter. If you need further assistance troubleshooting your vehicle, then seek out a technician, such as one from YourMechanic, that can assist you with the hesitation of the engine.

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