2003 Ram 1500 4.7 Low Power when accelerating.

[Troyboyyy]

Just purchased a 2003 Ram 1500 4x4 Reg Cab with the 4.7 today. On my drive home I swung by Walmart and grabbed some stuff, ater coming out and getting back into the truck i went to drive off and the truck seemed to be struggling to accelerate, after a second or two giving it more gas it finally caught. This is my first truck and Ive only owned it for a few hours. Any ideas on where I should begin? Some common problems this truck may have? If not ill probably just buy a ton of stuff nd start doing some maintenance lol ( Plugs, Wires, PCV, Clean the TB, does this truck have an in-line Fuel filter?, new MAF...those kinds of things) Thanks in advance!

 

[jws123]

Scan for codes how many miles on it?

 

[Troyboyyy]

Scan for codes how many miles on it?

Will scan for codes soon. 138k miles

 

[HemiBrother]

My 03 grand Cherokee started acting like that when the cats were starting to fail just something else to check out. It would seem almost fine for my first trip into work but on my way home after work it would seem half the power. Was driving me nuts replaced plugs, pvc, and cleaned throttle body then it finally threw a bank code then it dawned on me what the true problem was. Sure enough when I dropped the cats and took a peak inside I was shocked it even ran. Not saying that’s your problem but something to look at.

 

[Troyboyyy]

My 03 grand Cherokee started acting like that when the cats were starting to fail just something else to check out. It would seem almost fine for my first trip into work but on my way home after work it would seem half the power. Was driving me nuts replaced plugs, pvc, and cleaned throttle body then it finally threw a bank code then it dawned on me what the true problem was. Sure enough when I dropped the cats and took a peak inside I was shocked it even ran. Not saying that’s your problem but something to look at.

Funny you should mention that. When I looked under the truck the day I got it (Saturday) it looks like someone had done some work to the exhaust/cats. Looks like a horrible job too and the cats look like they where made in someone’s garage

 

[Troyboyyy]

Scan for codes how many miles on it?

P0141 and P0440

 

[Marshall]

Dealer? make them fix it.

 

[Troyboyyy]

Dealer? make them fix it.

Nope not from a dealer.

Also looks like my upstream o2 sensor is a Bosch. I read somewhere Bosch brand o2 sensors are known to cause issues in the Dodges? Also the are splice yourself sensors maybe whoever wired it did it wrong? But I cleared the codes and they stayed away for the time being. Might remove the Bosch sensor and tap the threads so it seats properly and maybe replace the Bosch sensor with another brand

 

[HemiBrother]

P0141 That’s bank 1 downstream oxygen sensor. That can make it run like crap. P0440 is for evap could be a variety of different things there from bad gas cap to bad leaky hose somewhere in the evap system again can make it run like crap.

 

[HemiBrother]

Whoops sorry wrote all that before the pictures were posted haha so found some of your issues right there. But incase you didn’t know bank 1 is the side that cylinder one would be on and it would be the sensor after your cat if I remember correctly.

 

[Troyboyyy]

Whoops sorry wrote all that before the pictures were posted haha so found some of your issues right there. But incase you didn’t know bank 1 is the side that cylinder one would be on and it would be the sensor after your cat if I remember correctly.

My 4.7 has the exhaust that comes down to a y-pipe before the cat. I only have 1 upstream sensor and one downstream. Not the typical 4 sensors. I hear that’s also a rare setup? lol

 

[jws123]

Yes never use Bosch o2 sensors nothing but problems on dodge/jeeps ive been burnt to many times lol.

 

[Troyboyyy]

Yes never use Bosch o2 sensors nothing but problems on dodge/jeeps ive been burnt to many times lol.

Going to replace it tomorrow and see if the code stays away! Thanks.

 

[Fast69Mopar]

Going to replace it tomorrow and see if the code stays away! Thanks.

Neither one of those DTC's are going to cause a "low power" condition. The P0141 is for the O2 heater circuit which the PCM monitors. The oxygen sensor has a heating element inside of it to heat up the sensor so that it starts working faster. When the heating element has high resistance or an open circuit the DTC will set. Since you said it was a "wire-it-yourself" sensor it could very well be wired incorrectly.

Now,.with it being a Bosch sensor there is an easy way to tell if it is attributing to your low power condition. With a scan tool look at the Bank 1 adaptive memory and the Bank 1 Long Term Fuel Trim. The LTFT or Long Term Fuel Trim is directly related to the downstream O2 sensors. When the STFT or Short Term Fuel Trim starts to get to far away from 0% whether is be plus or minus the LTFT starts to make adjustments to bring the STFT back to zero. The fuel trims are basically a correction factor for the PCM. When the PCM recognizes a need for more or less fuel it will increase the STFT to keep the engine operating as designed. When the STFT starts to get out of band the LTFT steps in to bring it back to a kevel-headed state.

If you have a scan tool or access to one take a look at the STFT and LTFT and it can help you determine if the poor running conditions are fuel related or not so you can look other places.

 

[Troyboyyy]

Neither one of those DTC's are going to cause a "low power" condition. The P0141 is for the O2 heater circuit which the PCM monitors. The oxygen sensor has a heating element inside of it to heat up the sensor so that it starts working faster. When the heating element has high resistance or an open circuit the DTC will set. Since you said it was a "wire-it-yourself" sensor it could very well be wired incorrectly.

Now,.with it being a Bosch sensor there is an easy way to tell if it is attributing to your low power condition. With a scan tool look at the Bank 1 adaptive memory and the Bank 1 Long Term Fuel Trim. The LTFT or Long Term Fuel Trim is directly related to the downstream O2 sensors. When the STFT or Short Term Fuel Trim starts to get to far away from 0% whether is be plus or minus the LTFT starts to make adjustments to bring the STFT back to zero. The fuel trims are basically a correction factor for the PCM. When the PCM recognizes a need for more or less fuel it will increase the STFT to keep the engine operating as designed. When the STFT starts to get out of band the LTFT steps in to bring it back to a kevel-headed state.

If you have a scan tool or access to one take a look at the STFT and LTFT and it can help you determine if the poor running conditions are fuel related or not so you can look other places.

Update. Changed out the Bosch sensor and my check engine light has been off for 2-3 days now. Hopefully that fixed the CEL issue. I did however also find I have a leaking fuel injector (possibly contributing to my low/loss of power from time to time?)

Also installed new bumper lol

 

[Fast69Mopar]

Update. Changed out the Bosch sensor and my check engine light has been off for 2-3 days now. Hopefully that fixed the CEL issue. I did however also find I have a leaking fuel injector (possibly contributing to my low/loss of power from time to time?)

Also installed new bumper lol

Glad you got it sorted out so far.

 

[Troyboyyy]

Neither one of those DTC's are going to cause a "low power" condition. The P0141 is for the O2 heater circuit which the PCM monitors. The oxygen sensor has a heating element inside of it to heat up the sensor so that it starts working faster. When the heating element has high resistance or an open circuit the DTC will set. Since you said it was a "wire-it-yourself" sensor it could very well be wired incorrectly.

Now,.with it being a Bosch sensor there is an easy way to tell if it is attributing to your low power condition. With a scan tool look at the Bank 1 adaptive memory and the Bank 1 Long Term Fuel Trim. The LTFT or Long Term Fuel Trim is directly related to the downstream O2 sensors. When the STFT or Short Term Fuel Trim starts to get to far away from 0% whether is be plus or minus the LTFT starts to make adjustments to bring the STFT back to zero. The fuel trims are basically a correction factor for the PCM. When the PCM recognizes a need for more or less fuel it will increase the STFT to keep the engine operating as designed. When the STFT starts to get out of band the LTFT steps in to bring it back to a kevel-headed state.

If you have a scan tool or access to one take a look at the STFT and LTFT and it can help you determine if the poor running conditions are fuel related or not so you can look other places.

 

[Troyboyyy]

Engine light came back on after a few drives. Same codes. Downstream heater etc. That sensor looks brand new (see pictures above) I check my fuse and it’s fine but I did notice the relay was missing. Says “v10 only” but I’m not sure if I should install one anyways.

 

[jws123]

Engine light came back on after a few drives. Same codes. Downstream heater etc. That sensor looks brand new (see pictures above) I check my fuse and it’s fine but I did notice the relay was missing. Says “v10 only” but I’m not sure if I should install one anyways.

what brand is the sensor

 

[Troyboyyy]

what brand is the sensor

Not to sure. I went ahead and just got a new one. Tested power and ground to the sensor and everything seemed fine. I’m just hoping the previous owner got a dud sensor off eBay and this will fix my problem. Will keep anyone posted.