I have a 2003 Dodge Ram 1500. Keep getting the same code on check engine light....Help!


Asked by Nov 29, 2013 at 06:55 PM about the 2003 Dodge Ram 1500 SLT Quad Cab LB

Question type: Maintenance & Repair

I have a 2003 Dodge Ram 1500 4wd, Club Cab.  Runs good except I keep getting the
same code on the check engine light.  Random misses Cylinder 5 & 6.  I have had the
oxy sensors replaced.  Replace the Spark plug wires twice. Replace the plugs twice.  
Replace the Distributor cap and rotor twice.  If I start the truck, let it idle for about 10-
15 minutes, I will have the Check Engine light come on.  Runs fine no noticable miss
that I can hear or feel.  Usually driving under normal conditions will not produce the
Check Engine light, unless I get stopped in traffic delays.  At times it will go off by
itself within a day.  I have been told sensitive on board computer, and just about
everything else.........  Anyone here have an idea??

20 Answers


What is the actual check engine code number?

4 of 4 people found this helpful.

Could be faulty fuel injectors on those two cylinders. HTH. -Jim

1 of 1 people found this helpful.

I should have stated that the truck has 157,000 miles on it. I have usually run the STP injector cleaner about every 2-3000 miles. I know that would not account for a faulty injector, so that will give me something to discuss. The code on my reader is either random misses(can't recall #), or 305 or 306. I am somewhat new to reading the codes....

2 of 2 people found this helpful.

http://www.obd-codes.com/p0305 --- check this out. Also have you completely cleared all the codes. Disconnect battery for at least ten minutes. Then drive to see if code re appears.

2 of 2 people found this helpful.


1 of 1 people found this helpful.

Yes, I have cleared the code and it has been cleared by a mechanic. Normally when I clear them, I clear them. Cut the truck off for about 30 minutes, then check for codes again. In the past, if I recall correctly my mechanic did as you said, cleared, disconnected the battery and eventually, the codes reappear.Not right away, sometimes within a day or a week. I have gone as long as a month before it returns........... Reading the page that you suggested, one of the firtst things that was done was the compression was checked and it was ok on all cylinders. He also checked the valves which at the time, about a year ago, were fine. Makes no sense to me, but then I will admit, I am not a mechanic.....

2 of 2 people found this helpful.

Does it have the 5.9L engine?

1 of 1 people found this helpful.

http://troubleshootmyvehicle.com/chrysler/3.9L-5.2L-5.9L/how-to- troubleshoot-a-misfire-1 --- this might help shed some light as to what is going on with it.

2 of 2 people found this helpful.

delete the space between (to- trouble) should be (to-trouble) for address to work. Sorry iPad issues again.


Random/multi misfire is code P0300. A P0305 code is misfire cylinder #5 and P0306 is misfire cylinder #6. HTH. -Jim

1 of 1 people found this helpful.

It does have a 5.9 Liter engine. In reading the recommended article, I recall Bill telling me he did check the spark to both Cyl 5 and 6. He is an older guy and was joking with his helper when telling me how he did it by holding the wire.(lol) He did not recommend I try it that way. I am not sure he moved the injector to another cylinder to see if the code followed it, but like I said earlier, the code does not appear quickly. As I'm sure you know, it is not easy to work on these as the engine sets way back almost under the dash, and some things have to be done almost by feel, especially on the back cylinders.


It has narrowed down now to the PO305 code, so as stated here I am leaning toward a bad injector. What is involved in changing an injector and should they all be changed or just the one?? Thanks for your help and answers...........

2 of 2 people found this helpful.

Personally I'd change all of them. In my opinion on an 11 year old truck if one has failed, the others are soon to follow. Unless you plan on selling it soon. HTH. -Jim

2 of 2 people found this helpful.

I agree with Jim.

2 of 2 people found this helpful.

OK, Thanks, is this major surgery, or something not too difficult just so I have an ideas of what I am looking at.......and no, I am not going to try it myself.........of course, everything on the truck has been difficult.......nothing wants to come out or off....LOL!

I have the same problem po305 I changed the fuel injector still coming on .unless I changed the wrong injector I don't know what's up

I see this was 2years ago ever figure out what was wrong


Well, I continued to work with my mechanic and he checked everything that had been covered here, without my input, and finally determined that a valve job was needed to remedy the situation.


It, as you know can be 1000 things wrong, However, if the truck is running fine, don't worry about it until your next inspection. Sounds like a sensor related to your pollution EVAP system........


Appreciate your answer, but all that was checked, injectors were changed more tests, and finally the valve job is what we were left with......

Your Answer

Ram 1500

Looking for a Used Ram 1500 in your area?

CarGurus has 10,845 nationwide Ram 1500 listings starting at $1,500.


Dodge Ram 1500 Experts

  • #1
    Dan Connell
  • #2
  • #3
View All

Related Models For Sale

Used Ford F-150
2,289 Great Deals out of 184,004 listings starting at $699
Used Chevrolet Silverado 1500
2,087 Great Deals out of 166,143 listings starting at $1,900
Used Dodge Ram 2500
159 Great Deals out of 4,989 listings starting at $2,499
Used GMC Sierra 1500
859 Great Deals out of 65,198 listings starting at $2,495
Used Toyota Tundra
441 Great Deals out of 32,126 listings starting at $1,999
Used Toyota Tacoma
639 Great Deals out of 42,801 listings starting at $1,500
Used Ford F-250 Super Duty
363 Great Deals out of 44,691 listings starting at $1,799
Used Nissan Titan
209 Great Deals out of 19,954 listings starting at $3,495
Used Dodge Dakota
115 Great Deals out of 3,737 listings starting at $1,000
Used Chevrolet Colorado
278 Great Deals out of 31,424 listings starting at $1,995
Used Dodge Ram 3500
82 Great Deals out of 2,234 listings starting at $3,950
Used Ford Mustang
689 Great Deals out of 37,936 listings starting at $895

Used Cars For Sale

2008 Dodge Ram 1500 SLT Quad Cab LB For Sale
11 listings starting at $6,995
2007 Dodge Ram 1500 SLT Quad Cab LB For Sale
4 Great Deals out of 15 listings starting at $5,995

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.