2006 Ram 1500 doing strange RPM things

[DerbyDodge]

Highway speeds this truck sometimes won’t get over 1000 RPM. Other times it’s fairly normal… it could be between 1000 to 1800 on any given day. Town speeds between 35-55 RPM are 500-800. Sitting at a stop light? 200 RPM.
The engine doesn’t sound terrible, if you weren’t looking at the dash sometimes it would be hard to tell.
Spark plugs changed in February, fuel pump changed in March, oil changes religiously.
Any ideas or experiences?

 

[fastf]

Is there a way you could hook up a separate tach and see if your tach is going bad.I just remembered the computer runs everything sorry my bad.

 

[Karlsweg]

Your tach has to be wrong because there is no way at idle it would be 200 rpms or 1000 at 70!

 

[Fitz-0518]

Yep. And it could be as simple as re-calibrating the tach. A knowledgeable tech with the right type of scanner can go in the factory spec and performance side of your ecm an "might" be able to,,,, like re set.

 

[SYKRAMMAN]

Cluster maybe going bad, is anything else happening? I.e. any lights not working, things coming on when not turned on, any weird stuff that you can’t explain, etc, etc.

 

[Fitz-0518]

Very possible. The elec module on the side of our throttle body's, effect many operating conditions.

 

[DerbyDodge]

I didn’t think 200RPM was conducive to life but it hangs out there a lot.
I’ve not had any weird happenings… occasionally the wipers do what ever they want after I’ve turned them on.
I did have a mechanic tell me it was my EGR but it’s not throwing any codes and the CEL doesn’t come on.

 

[SYKRAMMAN]

I didn’t think 200RPM was conducive to life but it hangs out there a lot.
I’ve not had any weird happenings… occasionally the wipers do what ever they want after I’ve turned them on.
I did have a mechanic tell me it was my EGR but it’s not throwing any codes and the CEL doesn’t come on.

No, definitely won’t run at 200 r’s. More than likely it’s an electrical issue but I could be wrong, it could be just a bad cluster. See if you can get ahold of a known good cluster to try, it’s pretty simple to remove, couple screws n clips. At least you’ll know if it’s that or not. Check your grounds, make sure they are clean and have a good connection. I don’t the egr has anything to do with your issues.

 

[Damndodge02]

Highway speeds this truck sometimes won’t get over 1000 RPM. Other times it’s fairly normal… it could be between 1000 to 1800 on any given day. Town speeds between 35-55 RPM are 500-800. Sitting at a stop light? 200 RPM.
The engine doesn’t sound terrible, if you weren’t looking at the dash sometimes it would be hard to tell.
Spark plugs changed in February, fuel pump changed in March, oil changes religiously.
Any ideas or experiences?

Did you ever figure this issue out? I'm having the same issue. I know I know my truck is 3rd

Highway speeds this truck sometimes won’t get over 1000 RPM. Other times it’s fairly normal… it could be between 1000 to 1800 on any given day. Town speeds between 35-55 RPM are 500-800. Sitting at a stop light? 200 RPM.
The engine doesn’t sound terrible, if you weren’t looking at the dash sometimes it would be hard to tell.
Spark plugs changed in February, fuel pump changed in March, oil changes religiously.
Any ideas or experiences?

No, definitely won’t run at 200 r’s. More than likely it’s an electrical issue but I could be wrong, it could be just a bad cluster. See if you can get ahold of a known good cluster to try, it’s pretty simple to remove, couple screws n clips. At least you’ll know if it’s that or not. Check your grounds, make sure they are clean and have a good connection. I don’t the egr has anything to do with your issues.

 

[Damndodge02]

Did anyone figure this issue out? I'm having the same issue with my 02! When sitting in drive or park 200-500 all day today it showed 200. When driving my usual 30 miles home today on the interstate rpms would only build up to 1500-1800 at 80mph. Also speed is off about 3-4 mph. Any body that can help I'd be grateful. Bought the truck about 2 months ago and been going broke trying to work all this issues out.

 

[10 Break]

Now that our 3rd gens are long in tooth and have "character" I wonder how many of these issues could be cured by inspecting / cleaning / repairing battery / body / block grounds.

 

[LoneWolf3574]

So this is a fairly typical issue with the 3rd Gen cluster. There are 2 IC chips that have either broken their solder connections to the board and it can be one or both. YouTube has numerous videos on this exact problem showing how to fix yourself and how to prevent it from reoccurring. Just do a search for "dodge ram tachometer repair" and you'll find what you are looking for.

EDIT - Good idea 10 Break, that will fix the other gremlins that tend to pop up over time.

 

['06 Ram 2500]

My ‘06 2500 tachometer was acting up and now stays at zero. Not a big deal just waiting for it to cool down in Houston before I spend the time to disassemble the dash and resolder the chips. Will also install some computer board washers to prevent any further issues. It is totally DIY if you have the time.