Throttle Body Replacement

Tbates57

New member
2008 Grand Cherokee 3.7L repacking throttle body how do I do the idle speed relearn? Also any advice on the replacement I have never done one before. Thanks
 

So I'm going to ask some questions first so I give the best directions I can.

Why are you replacing the TB?
And what are you replacing it with? Same! Bigger, from junk yard, ??


Regards,
JPNinPA

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The red lightning bolt dash light came on and when I replaced the accelerator position sensor the light remained. I was told by mechanic that is was one of the two. Replacing with the same body bought it from parts store.
 
Ok
Have you checked for CEL codes?
To check without starting the engine turn the key from the off to on position three times within 5 seconds. Too fast it doesn’t work. Look at the odometer for the output followed by done. Write down and report back the codes.
Have you reset the pcm and cleared the codes?
Once recorded you may need to reset for the new part to be acknowledged or learned. Basically remove pos battery cable touch to neg for 10 sec and reconnect. Then turn key on without starting. Headlights on. Headlights off then key off.

If not cleared:
First get your battery load tested.
Clean the cable connections to the battery and the opposite ends of the grounds. Remove sand to a shine and reconnect.
Check all fuses
Check the connections to the TB sensors. iAC and TPS.

If you changed any sensors did you use OEM?
These jeeps are fussy and many aftermarket ones are bad out of the box.


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I got three codes they were: P0455, P0456, and P2181. Thanks
 
P2181 is your temp sending unit.
Check the connection and repair.
Replace it with OEM sensor.

P0456 and P0457 notes a large evaporator system leak. Check the hoses in the evap system. One of the valves may be bad.


If you changed the TPS was it an OEM one? That may be the issue. You need to reset the PCM as noted above.
 
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I just did the reset as stated above and now it won’t start at all. When I turn key lights and radio come on but no crank.
 

Check battery connections. They corrode and so does the wires.
Get the battery load tested. Start with measuring the battery voltage. It should read 12.6V key off. Engine running 14.4V

A failing battery will cause false codes.

So you disconnected the positive battery cable. Then touched the positive cable to the negative. Correct? You didn't short the battery? Did you?


Regards,
JPNinPA

Sent using TapTalk
 
Yes that is what I did positive disconnected touched negative. The battery had a month left of free replacement so I went and got brand new one. Still no crank, connections tight and clean.
 

Wow. Okay. Ugh... I didn't imagine would happen.

Did you change the accelerator position sensor because of the lightning bolt light?

Any clicking when you turn the key?
If you turn the interior lights on and try to start do the lights dim?

Start with checking your fuses.

Check the connection to the starter and the ground connections. Esp the one to the engine.



Regards,
JPNinPA

Sent using TapTalk
 
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Yes I changed accelerator position sensor because of red dash light. When I turn key part way lights come on radio turns on them when try to start radio goes off no crank
 
Your starter may be shorted. With a new battery if the dome lights are on when starting there is a minor dimming. With a bad starter they dim greatly. Same with halogen headlights.

As for the lightning bolt, the first check is battery health and wiring.
After that check fuses then connections at the throttle body.

A bad weak battery will set all kinds of erroneous codes. That's because many codes are based on proper voltage settings not being met.

Is the Lightning indicator on solid or blinking?
Did you have drivability issues?

Thanks for reading all and answering all questions. It gets frustrating when questions don't get responses. It makes it harder to eliminate causes.



EDIT:
Just came across this procedure relating to the Lightning bolt indicator.

"To reset the electronic throttle control system, perform the following:
Insert ignition key and turn to "ON" position but do not start the engine
Wait for all the warning lights to go out. The check engine light may remain on.
Slowly depress the accelerator pedal all the way to the floor.
Slowly release the accelerator pedal until it is all the way back up at the rest position.
Turn the ignition key to "OFF" position.
Start the engine and test the throttle by see if the engine will throttle up."

This needs to occur each time your battery is disconnected or changed.







Regards,
JPNinPA

Sent using TapTalk
 
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At 2:50 starts the above procedure

This one is replacing the TB. If you get there.
I think you have a charging issue that needs to be fixed first.




Regards,
JPNinPA

Sent using TapTalk
 
So there is a brand new battery in the jeep now. When I turn key lights and radio come on. When I try to start there is no crank at all so no start. The radio turns off as well as any climate control but there is no dim to dome lights at all. Battery is fully charged and brand new so no corrosion all connections tight. Before resetting the pcm it started and ran fine other than check engine light and red lightning bolt light and fluctuations in idle speed. Now after reset it won’t start at all.
 
Sorry missed one question: the red lightning bolt is solidly lit, goes away sometimes for short period of time but then comes back
 

Do you have wireless keys or fobs?
The SKEEEM system may need rebooting. This should get it started.
Simple disconnect the battery fir 15-30 min. Some say to keep the pos and negative battery terminals tied together for an hour. Reconnect and start the vehicle. You may need new key batteries.



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Found this for security reset.

Step 1

Enter your Jeep and press the Lock button on your keyless remote five times in 10 seconds.

Step 2

Insert your key into the car's ignition, turn it to the "Run" position and wait for the car's chimes to stop.


Step 3

Press and hold the "Unlock" button on your remote, and then press and hold the "Panic" button while still holding "Unlock." Hold both buttons together for one second and release.

Step 4

Wait for a chime to sound and press and release the "Lock" and "Unlock" buttons on your remote.

Press and release the "Lock" button by itself and wait for the car's chimes to sound again to indicate successful resetting. Remove the key from the ignition when you are done to finish the procedure


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I went to try the anti theft process just a bit ago and just thought to try one last time before doing that. I started right up no dash lights on at all including red lightning bolt. I am going to drive it around a bit to make sure nothing comes back I will post the results. Thank you very much for all the help it is very much appreciated. I am not sure why it decided to start but it did.
 
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