P0174 and P0171 Codes

[GreenMountanTJ]

I recently replaced the PCM on my 2005 wrangler 4.0 auto, and that fixed the majority of the codes that it was throwing. It idles and drives fine, however, I am still getting recurring P0174 and P0171 codes. After reading some forum posts I took a look at the throttle body, and found that the crankcase vent tube seal was split on the manifold side. I used duct tape and a zip tie to seal and clamp this shut, so that now whatever air does make it through is hopefully inconsequential. On top of this, I used zip ties to secure the connector on the tps sensor, as I read that it being loose can cause problems. I also cleaned the throttle body. However, since these where all small changes, I'm guessing that there not the cause of the codes. On top of this all the o2 sensors are a year or less old. From what I've read the fuel pump or filter could be the issue, but I'm hesitant to replace it in case its not the problem, and I need a $50 part if I want to test fuel pressure since the 05's didn't have valves on the fuel rail. Does anyone who's had these codes before have an idea of what could be causing this? I'll post the code's freeze frame data down below.

DTCFRZF: P0174
Fuelsys1: CL
Fuelsys2: CL
LOAD_PCT(%): 16.1
ETC (F): 208
SHRTFT1: 6.3
LONGFT1: 23.4
SHRTFT2: 5.5
LongFT2: 31.3
MAP (inHg): 4.4
RPM (/min): 2127
VSS (mph): 35
SPARKADV: 20
IAT (F): 82
TP (%): 12.5

 

[CharlesHS]

When you state you cleaned the throttle body; did you remove the throttlebody from the intake manifold and thoroughly clean the internal ports as well as the throat of the throttle body ? There is a vacuum port for the MAP sensor that indicates manifold pressure to the ECU to adjust fuel injector pulse duration.
Both of those codes indicate a lean operating condition which can be caused by a vacuum leak or exhaust leak where the tubes from the cylinders join...
Start looking at the exhaust manifold for exhaust leaks and test around the throttle body base and around the intake manifold flange using water spray.

 

[GreenMountanTJ]

When you state you cleaned the throttle body; did you remove the throttlebody from the intake manifold and thoroughly clean the internal ports as well as the throat of the throttle body ? There is a vacuum port for the MAP sensor that indicates manifold pressure to the ECU to adjust fuel injector pulse duration.
Both of those codes indicate a lean operating condition which can be caused by a vacuum leak or exhaust leak where the tubes from the cylinders join...
Start looking at the exhaust manifold for exhaust leaks and test around the throttle body base and around the intake manifold flange using water spray.

I don’t think it’s an exhaust leak since there are 2 exaust manifolds, and I’m getting codes from Bolth banks. There is a hissing sound coming from the throttle body but I think it might be normal since I sprayed the gasket with starter fluid and nothing happened

 

[CharlesHS]

The sound you are hearing at the throttle body while the engine is running is the engine drawing air into the throttle body. IF you sprayed the starter fluid near the TB gasket and there was not change; then the gasket appears to be good, but you should still check the 4 bolts holding the TB to the intake manifold.
There are not two exhaust manifolds;\, but there are two banks for pre catalytic converters with Inlet and Outlet O2 sensors.

There is something that is causing a LEAN condition evidenced by these codes.
I would still thoroughly clean the throttle body paying close attention to the ports for the IAC and MAP.

 

[GreenMountanTJ]

The sound you are hearing at the throttle body while the engine is running is the engine drawing air into the throttle body. IF you sprayed the starter fluid near the TB gasket and there was not change; then the gasket appears to be good, but you should still check the 4 bolts holding the TB to the intake manifold.
There are not two exhaust manifolds;\, but there are two banks for pre catalytic converters with Inlet and Outlet O2 sensors.

There is something that is causing a LEAN condition evidenced by these codes.
I would still thoroughly clean the throttle body paying close attention to the ports for the IAC and MAP.

Ok thanks, I’ll pick up a gasket soon so I can take the throttle body off and clean it thoroughly. By pay attention to the map and iac ports, do you mean clean them too, or to not get throttle body cleaner in there?

 

[Jerry Bransford]

Whose PCM did you install, was it from @Wranglerfix or from someone else? WranglerFix.com is the only company I'm aware of that has a PCM with all the factory's software bugs programmed out. Those bugs are big problems for 05/06 PCMs.

 

[GreenMountanTJ]

Whose PCM did you install, was it from @Wranglerfix or from someone else? WranglerFix.com is the only company I'm aware of that has a PCM with all the factory's software bugs programmed out. Those bugs are big problems for 05/06 PCMs.

Yes it was a wranglerfix pcm, and it’s worked great

 

[CharlesHS]

Ok thanks, I’ll pick up a gasket soon so I can take the throttle body off and clean it thoroughly. By pay attention to the map and iac ports, do you mean clean them too, or to not get throttle body cleaner in there?

Remove all the sensors from the TB before cleaning and ensure the ports for the IAC and MAP are clean. The IAC has a disc and inside the cavity where the IAC is mounted is a seat that the IAC disc seats onto; ensure the debris is removed from the seat.

 

[Wranglerfix]

@GreenMountanTJ Both of those codes lead back to exhaust and an air intake leak. Have you had the Jeep smoked for leaks?

 

[GreenMountanTJ]

@GreenMountanTJ Both of those codes lead back to exhaust and an air intake leak. Have you had the Jeep smoked for leaks?

I’m hoping to resolve the issue without having to pay a shop anything. If I can’t fix it myself I’ll take to to a shop to look for leaks.