2003 ram 1500 5.7l P0108

[labiezer]

Hi, I have a 03 Ram 1500 with a 5.7l hemi, I started getting a thunderbolt light indicating throttle issue. I bought the car used, the previous owner and said he replaced the throttle for the same fault. also produces p2106 (from what i read p2106 can be caused by the P0108,

I started with a throttle cleaning it wasn't too bad but that's what causes it on VW. After the throttle it got better till it got cold again all summer truck drove great, so i proceeded to install a new throttle, as I know a vacuum issue can cause the same concern. still no change and has gotten worse, put old throttle in and the same since it's a circuit high fault I thought of adding a ground to the circuit as that could be an issue, that got me about week or 2 and then the same thing. obviously it is a sporadic issue, just not sure which way to go with it, should I overlay the signal wire next?

Is it possible the intake is heavily carboned causing this?
Since it is intermittent i don't think it's an ECM issue as all the 5v reference wires come from the PCM. and it is only the map sensor throwing a fault. I am relatively novice with domestics, very experienced with German cars.

Any help would be appreciated.


quick edit, after I replaced the throttle, it stalled on me and was hard to start, i only had the same 2 faults. I have access to all data and an ok scan tool that reads data.

also not my best decision I admit but i did have other faults prior to throttle replacement that led me to replace the throttle, replacement throttle is a Chinese part, as a tech I always say to use OEM parts on German cars but i figured it might be ok on a domestic. feel free to call e out on this if you think its the cause, OEM throttl is just so expensive..

 

[GTyankee]

You might try this

2008 Dodge Ram 1500 - MAP Sensor Replacement

In this video, I demonstrate how to replace the Manifold Absolute Pressure (MAP) sensor in my 2008 Dodge Ram 1500 5.7L Hemi.I am not a professional mechanic,...

www.youtube.com

 

[labiezer]

I already replaced the map sensor no chage. issue is getting worse so I am leaning towards an OEM throttle (if i have to do that i will upgrade to the mmx 87mm throttle) or the engine harness.

 

[2005DRAM2500]

Did you ever get a solution for the problem?

 

[labiezer]

I have yet to resolve the issue, I borrowed a scan tool from work and attempted to compare some data, i also installed an OEM map sensor, the reading did change slightly but not much, but still have the same issue, i did an etc relearn with the scan tool and now i have no acceleration since i also have a stiff pedal I replaced the pedal position sensor under the battery, Orielly's has them in stock they say it's for the manual, but it is the same part. tried to readapt but i have the same issue with all 4 adaptation faults, i did a graph on the apps sensors and found sensor 2 drops out completely to 0. Sensor 1 has a small drop but not major.

I suspect this was my issue the whole time, I jumped pin 2 to pin 1 got 5volt reference but it still drops out, did the same with pin 3 and also it drops out randomly, ont suspect a wire at this point or a faulty sensor as i get the same readings, only thing left is the ECM, I compared the graph reading to the borescope reading in all data and in ALLDATA the signal never drops out, I also disconnected all other sensors in the circuit to eliminate a potential feedback issue or sensor shorting taking out the 5v reference, but since there are 2 separated 5v references and the both drop to 0 when shorting to pin 1 i believe is an internal ECM driver failure causing the issue, the voltage drop is not very consistent but enough to where it would cause the throttle relearn to fail.

Unless someone thinks otherwise (please let me know) I will be ordering an ECM...

 

[2005DRAM2500]

I bet it's the ECM. Ask me how I know this!
Had a 2005, 1500 with the 5.7.
New from dealer. Constant lightning bolt light. They tried everything to fix it multiple times. Total parts cannon. Problem always came back. Dealer would not put in a new ECM.
But I knew it had to be the ECM. I lived with it until the truck got totaled by a 19 year old running a stoplight.

Honestly, if I had another RAM with the never-ending lighting bolt light I would make them take the truck back. It was an extremely frustrating experience!

Good luck!

 

[2005DRAM2500]

BTW:
This is the TB you should have bought.
It's made by the OEM.
Available at Rock Auto.