I have read a bunch of posts online about this issue. I saw alot of replys like it is the delay in the pedal and the trans it is bolted to as if it was a very common issue. My problem just started about 2 weeks ago. When you push the gas pedal from a dead stop it boggs down and hesitates then kicks in and throws you back in the seat. Not fun parallel parking. Took it to my shop and it had an egr code P0406. I'm at 50,000 miles so they did the plugs and egr valve. Cleaned throttle body and ran some injector cleaner. Runs shifts and idles fine. Only problem is the initial acceleration. Engine light came on again today but i'm assuming it is just the old U1120 mystery code again. Been driving it for about 4 days now and it is still the same. Hate to take it to the dealer but I might have to. Just trying to find out what I might be up against.

 

Did they change the throttle position sensor with the tune-up?
FF

 

No. Never came up. Just overdue for plugs and the EGR code came up.

 

code p0406 should clear up with the EGR replacement. Other sites claim u1120 is the instrument cluster. Here is another thread about it:

https://dodgeforum.com/forum/2nd-gen...ine-light.html

FF

 

Tried to check code myself with the ignition on, off, on, off, on trick but it didn't work. Nothing came up in the odometer. Tried it a few times. Is that the correct way to check as listed on the Gen. 1 post.

 

Try Pyro's key dance (start does not equal turning the engine over):

https://dodgeforum.com/forum/3rd-gen...-for-this.html

FF

 

Happened the same thing to me with 5.7 ford, it was cheap spark plugs, changed them for platinum and MAGIC...Problem solved

 

U1120-LOST WHEEL DISTANCE MESSAGE




For the Engine circuit diagram (Refer to 9 - ENGINE - SCHEMATICS AND DIAGRAMS).

For a complete wiring diagram Refer to Section 8W.

When Monitored:
Ignition on.

Set Condition:
The PCM doesn't receive a wheel distance messagel from the Anti-lock brake Module over the CAN C bus.

Possible Causes
CAN C BUS CIRCUIT OPEN OR SHORTED
ANTI-LOCK BRAKE MODULE
PCM


Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

Theory of Operation
The PCM receives the vehicle speed signal over the CAN C bus from the Anit-lock Brake Module.

Diagnostic Test
1. ACTIVE DTC

--------------------------------------------------------------------------------



Ignition on, engine not running.
With the scan tool read Powertrain DTCs.

Is the DTC active at this time?

Yes
Go To 2

No
Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform (NGC) POWERTRAIN VERIFICATION TEST VER - 5.



2. U0121-LOST COMMUNICATION WITH ABS MODULE ALSO SET

--------------------------------------------------------------------------------



With the scan tool continue reading DTCs.

Is the U0121-LOST COMMUNICATION WITH ABS MODULE also set?

Yes
Follow the daignostics for U0121-LOST COMMUNICATION WITH ABS MODULE
Perform (NGC) POWERTRAIN VERIFICATION TEST VER - 5.

No
Replace and program the Powertrain Control Module per Service Information.
Perform (NGC) POWERTRAIN VERIFICATION TEST VER - 5.

 

I too am having this EXACT issue...any other answers/ideas?

 

o2 sensor....had same issue with my '96 Grand Cherokee. Took awhile to track it down, but what was happening was that the 02 sensor was taking too long to warm up. When the computer switched to closed loop mode, the o2 was indicating a lean condition (since it wasn't warmed up) so the computer started dumping gas into the engine. And that's why it ran like it was flooded.