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Chris
Chris, Car Enthusiast
Category: UK Car
Satisfied Customers: 12736
Experience:  Specialize in UK Chrysler, Dodge, and Jeep vehicles.
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I have a fault on my GC 5.7 (2006) when I slightly rev the

Customer Question

I have a fault on my GC 5.7 (2006) when I slightly rev the engine and take foot of throttle it carries on increasing revs for a few seconds maybe another(###) ###-####pm then drops back.
Submitted: 11 months ago.
Category: UK Car
Customer: replied 11 months ago.
Happens at all revs. Did find the air temperature sensor in the chamber between the air filter and throttle body had fallen out and hanging down. All back in, didn't make any difference. Only does this with a hot engine.
Expert:  Chris replied 11 months ago.

Hello and welcome to just answer. This is either a failing throttle body or the APPS (pedal position sensor). Do you have access to a scan tool that will read real time sensor data? If so, then we can determine if it is the APPS or the throttle body. Let me know if you have or can get/rent one.

Chris

Customer: replied 11 months ago.
I have a scanner with real time, APPS ? is that the TPS ?
Expert:  Chris replied 11 months ago.

The TPS is the throttle position sensor inside of the throttle body. The APPS is the sensor on the gas pedal. When you step on the gas pedal, that sensor tells the PCM (engine computer) where you have the gas pedal. Then the PCM sends a signal to the motor in the throttle body which moves the throttle plate. Then the TPS monitors the position of the throttle plate and sends that iinfo back to the PCM. Based on your symtom, it is probably the APPS, but watch that voltage signal while stepping and releasing the pedal. If it follows your fott movement exactly with no lagging, then the APPS is good. I hope that makes sense,

Chris

Customer: replied 11 months ago.
Yep very. Just looking in the Jeep manual, ok will check that first, was thinking of the motor that drives the throttle ?
Expert:  Chris replied 11 months ago.

Could be the throttle body motor, if so replace the complete throttle body.

Chris

Customer: replied 11 months ago.
My scanner dosent list the APPS only the TPS, also because it has this problem with the engine hot and been used for 30 minutes or so its difficult to check. I was thinking if I take it out for a run so it shows the problem. Take the airfilter etc off and watch the throttle open and close to see if it continues after the accelerator is released ? The output from the APPS, is there somewhere on the throttle body I can measure the resistance ?
Expert:  Chris replied 11 months ago.

That sounds like a good plan. If it only happens when hot, then it is probably the throttle body.

Chris

Customer: replied 11 months ago.
Will check and rank then. No point in nagging as its Xmas ! As soon as I've chech it out I'll give feedback.
Expert:  Chris replied 11 months ago.

Sounds good my friend! Merry Christmas to you and your family!!

Chris

Customer: replied 11 months ago.
Hi Chris, me again. Changed throttle body for a new one. no change or may actually be worse! Also cruise control not working.
Expert:  Chris replied 11 months ago.

Hmmmm, you may need to have a shop perform a throttle body relearn procedure on the new throttle body. That will require a scan tool that will force the PCM to learn the voltage values of the new throttle body.

Chris

Customer: replied 11 months ago.
will that have caused the cruise control issue ? The light comes on but doesn't engage.
Customer: replied 11 months ago.
What about a PCM reset somehow ? Battery off over night seems to be a general view ?
Expert:  Chris replied 11 months ago.

Yes. If the PCM does not know the voltage limits/values of the new throttle body, then it cannot set the cruise control requested speed. A PCM reset may or may not help. Try it first though.

Chris

Customer: replied 10 months ago.
Hi again, do you have the part number for the APPS ? Or the accelerator package as it look like you have to buy the pedal assembly with the APPS. Cant find it in my parts catalogue. In the official service manual its under Fuel Injection 14-30.
Regards
Expert:  Chris replied 10 months ago.

Yes I can find it. And it is part of the pedal assembly. I will look it up and get back to you.

Chris

Expert:  Chris replied 10 months ago.

Please send me the Jeep's VIN number so I can look up the correct APPS part number.

Chris

Customer: replied 10 months ago.
Hi Chris
1J8HDE8255Y586299
Should be a right hand drive 2006 Grand Cherokee Ltd 5.7
Thanks
Expert:  Chris replied 10 months ago.

Ok, thanks. Based on your VIN number the part number is ***** That is for a Grand Cherokee 5.7 with non adjustable pedals.

I hope this helps, and if I have been helpful, would you kindly take a moment to rate my service today?

Thanks,

Chris

Customer: replied 10 months ago.
Ive been offered a 52109685ac, is that similar?
Expert:  Chris replied 10 months ago.

Let me check.

Chris

Expert:  Chris replied 10 months ago.

Ok, yes that part number will work, it has been superceded from the one I gave you.

Cheers,

Chris