Posted on 06/12/2015 3:49:19 AM PDT by Cowman
I have a 2005 dodge truck with a 4.7 that has started running very rich to the point of choking out and it has a random cylinder misfire. The cruse was working intermittently and the dash lights would randomly go on and off. The mechanic changed a coil and cam sensor that did nothing but clean up a couple codes and suggested I change the ECM.
My question is: can I use a junkyard unit that I can change myself or does the new computer need to be reprogrammed for my vehicle by the dealer (I have heard both)
I don’t know the answer to your question, but I’d check the grounds to every cable you can find.
I have a similar era Chrysler and all the modules are VIN-encoded so they can’t be swapped between vehicles and supposedly can’t be reprogrammed, even by a dealer.
I don’t know if this was used on Dodges of the era.
But it sounds like there is something else going on than a problem with the ECM.
No junk yard. Get a rebuilt one. All have to be reprogrammed. Either way your looking at some bucks. Minimum of $900.
Indeed. Start right at the battery.
There are some Dodge forums, maybe post a question there.
Here’s one:
https://www.allpar.com/forums/forums/ram-pickups-commercial-trucks.6/
2) Have the O2 Sensor(s) ever been replaced ?
3) Have the Spark Plugs ever been replaced ?
4) Have the Plug Wires ever been replaced ?
I may have more ? after getting these answered.
If You need Parts go Here
Also have Autozone Test the Battery AND Charging System. Fuel Injection ECM’s need a MINIMUM of 10.8 volts or they don’t function properly.
Durangoclub.net is a great place for info on not justDurangos but links to Dodge trucks.
Dodge trucks are very sensitive to battery problems, ground connections.
I had a similar problem with my Durango and it was a bad battery cable.
Check your Oxygen or Air Flow sensors. I recently had the same problem with an Outback. Every time I went up or down a hill, made a sharp turn, or accelerated, it would stall. I found a broken wire on the Mass Air Flow sensor. Replaced it and now it runs just fine. Good Luck.
Rockauto.com is the best thing since sliced bread.
Tour truck is OBD II. It has extensive built in diagnostics, get a full readout first.
You can also get a reader that wirelessly connects to a laptop and give you real time info on what is happening while the engine is running, and which sensors are inop or out of range.
That said, Dodge has a BIG problem with their electronics. Best get to a Dodge truck forum and ask questions there. It may end up you need to get rid of the truck if you can’t do the work yourself.
This may or may not help, but since the problems are multiple and electrical in nature you should probably take a look at the grounding cable and wire(s), particularly where they are secured to the frame, inner fender well, etc. Over time, corrosion can cause bad connections.
My first efforts at fixing ‘random vehicle electrical gremlins’ are always aimed at the electrical grounding system. After checking the connection at the battery, I completely detach the other end of the main ground cable from the frame and use a wire brush to remove rust scale and any other corrosion from the vehicle frame and the cable’s mounting lug. I then reattach it with a new bolt and washer. If there is any sign of breakage or weakness in the cable or its mounting lug I replace the entire ground cable. I then do the same thing with the smaller gage wires at any/all secondary grounding locations. Those wires can e hard to completely replace so I usually settle for attaching new mounting lugs to the existing wire if there is any question about its integrity.
Depending on the vehicle, there may be several secondary grounds at various locations. They are usually on the frame or an inner fender well in the engine compartment.
It sounds like a lot of work but it’s really not that bad, and if it fixes the ‘gremlins’ then you’ve saved the cost of one or more expensive electronic components. If it doesn’t, then at least you’ve verified that a ‘bad ground’ is not the problem.
Nah, Rock Auto
$439.79 ECM $125.00 Core $564.79 Total
Depending on what Dodge Truck- these $ are for a 1500 w/4.7
Yep! And I spent 18 years selling parts. They have Great Customer Service and Prices. Any problems that are within Their power to fix they do.
I got a T/S Flasher Relay last year and it turns out there were 2 options, I ordered the wrong one and it made the T/S blink fast. Called them and they shipped the correct one at N/C and told Me to toss the wrong one in the trash.
I gave it to Our Local shop that does State Inspections for Us since it was new. They have done Us a few favors over the years so I figured what the heck.
After a long time of not playing auto electrician, I’ve relearned that method with endless aggravation on my old ragged jeep collection.
O2 and Mass air sensors first to check. Get a code reader and/or a mechanic with experience in 21st century electronics
I seriously doubt it’s the ECM as the vehicle is running. Just don’t shoot a parts cannon at it and hope for the best as there are many things and thousands of dollars to spend shotgunning drivability issues. Pay someone with the proper diagnostic skills and equipment to do real time scanning and you will be dollars ahead.
Bingo!
Also check or just get a new Lug to Lug to Lug Battery Cable an go from Bat - to Engine Block and Fender (Chassis)
There is probably a Ground under the floor mat/carpet on the Drivers side to check also.
Autozone and most other Parts stores will do it for free.
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