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Matt, Engineer
Category: Australia Car
Satisfied Customers: 21995
Experience:  Automotive Engineer for 20 years, BEng hons degree,
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I have a 2010 Diesel Prado. I have been having some problems

Customer Question

I have a 2010 Diesel Prado. I have been having some problems for a little while but are now becoming mush worse. it started with an occasional power drop but no it is happening all the time. usually when you go over a bump (which is great since we live on a dirt road) but can also happen on the highway. it also surges sometimes. the cruise control now does not work at all. originally when it first started when the power drop would occur the cruise control would also cut out and could not be reactivated unless you stopped and shut down the engine and then restarted. Now i cannot get it to work at all. I have been to 3 different mechanics, the computer says it is a throttle position sensor and I have had the throttle body replaced that should have also replaced the TPS. one auto electrician suggested it might be the accelerator pedal but not convinced of this as the cruise control cutting out is not linked to the accelerator. sometimes even closing a door can trigger a surge. Hope you can shed some light on this.
JA: Does the vehicle hesitate during acceleration? Or maybe speed up suddenly when you aren't even hitting the gas?
Customer: Yes
JA: What is the make/model of your car?
Customer: 2010 Toyota landcruiser Prado Diesel with the D4D engine
JA: Are you hoping to fix this yourself? What have you tried so far?
Customer: Happy to get someone to fix it or if I j know what is causing the problem i will fix it myself but so far noone (including Toyota) can shed any light on the problem. The throttle body has been changed and the optical unit in the accelerator pedal has been cleaned.
JA: Anything else you think the mechanic should know?
Customer: No I think that covers it. I have checked to make sure all the plugs are fitting tightly and nothing appears loose.
Submitted: 1 year ago.
Category: Australia Car
Expert:  Matt replied 1 year ago.


this sounds like a bad electrical connection thats making and breaking when you pass over bumps

As you have a code for TPS related issues I'd next carefully inspect the connections to the pedal and the wiring runnign to it

disconnect the pedal and clean the pins with some switch cleaner 1st and then trace the wire back into the main loom , checking for chafed insulation and hard sections of wire

I'd also check over the ECU power supply relay and fuses for signs of corrosion and possible cracks

if this is all OK I'd check over the battery connections for tightness and corroded connections

Expert:  Matt replied 1 year ago.


do you still need help?

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