I replaced a 2003 ram 1500 4.7 with a 2002 ram 1500 4.7.Every thing hooks up except the throttle sensor and intake air sensor.If I change the intakes will it work?
Changing your intake so you have your original set-up would work, But before doing so, is there any way to just change the throttle body, or what ever is on there to the one that was on? Or I would investigate a bit further on doing something with the sensors, replacement maybe...just my 2 cents...
I changed the throttle body but it wouldn't start.In 2003 they did away with the sensor on top of the intake,so there is no wire to run the intake air sensor on the 2002.
So, that sensor is just sitting there, not causing any problems? See this would be ok for your computers programming since you have no wire. And you changed the throttle body, the one that was on originally? No problems or conflicts there?
No it fit perfectly.Let me ask this,what's the easiest way to check to see if I'm getting fire from my pcm?
Thats what I was thinking but not the ecm, thinking about spark and fuel. I would think this thing should fire up. Check for spark from the coil wire, or threw a plug wire. Another thing would be to check to see if there is power around the different sensors, especially at the coil. A simple test light would suffice.
OK thanks.Has coil over plugs so I'm pulling a plug now to check.
Researched some more but seems to be a lot of confusion.How do you know for sure which tone rings are on the motor.Some say the 8th letter in vin and some say pcm.
What is tone rings...
They are on the crankshaft and camshaft and have to do with the timing.Best I can tell they tell the computer when to send fire.
Camshaft sensor, & crankshaft sensors, I forgot about, usually the crankshaft sensor goes bad. This does not tell computer to send the fire, but monitors the position of the crankshaft, any deviation it picks up will affect the firing of the engine, Not sure if those can be tested, more than likely tho. This motor will run, just have to figure out the spark thing. Oh the sensors are visible on the front of the motor, Crankshaft sensor should be on the side of the timing cover down by the timing marks.
Ya I know about the sensors but the tone rings are mounted on the crankshaft and the camshaft and tell the sensors the info to send the computer.They went from 16 tooth to 32 tooth sometime in 2002 from my understanding,but I can't find a clear way to tell what I have yet.I am hoping they are the same and you are correct about it but I'm stumped right now.
I believe you are on to something here, That makes sense. Meaning you may have the 16 tooth & you would need a 32 tooth. Anyway of looking on the old motor? Your computer would be set for a 32 tooth. I will see what I can find out from my sources.
I have ben researching this all day. Here is what I came up with. First do you know for sure if that motor cam out of another 2002 Dodge Ram? And would you have access to that chassis to read the vin number? The eighth digit would be "N" for a 32 tooth reluctor ring, (tone ring). Also chances are that it is a 32 tooth ring if it came out of a 2002 Ram. I only came a-pond one source saying that the 2002 4.7 came with a 32 tooth ring. I even called our local dealer to try and verify, but they couldn't even tell me how many teeth are on the part if I were to order it. (dealer item only) But I do know that motor will run in your truck. Even if it is a 16 tooth tone ring, they change them out for installation into a newer vehicle. The only other way to tell for sure would be to drop the oil pan as it is bolted onto the crankshaft toward the rear, and count the number of teeth. If it would be a 16 tooth, the motor would have to come out and the crankshaft removed to replace it with a 32 tooth tone ring...Ideas?
The motor came from a 2002 I've been driving and went into a 2003 I bought.The letters in the vin are both N,but what I'm reading is pretty much that the 3 prong pcm is 16 and the 4 prong is 32,and they actually put someof both in the 02 trucks,but cannot get a definite on that.Like you said,even the dealers don't know.Guess I'm just gonna have to drop the pan and count.I was hoping there was an easier way but guess not.If it is different I'll probably just rebuild the one I took out since I would have to go all the way thru the other one to get to the ring anyway.I really appreciate your time.
Then what about switching the pcm's and wire harness? Doesn't make sense to me at the moment, gotta think, If you have a 32 tone ring in both motors and all your plugins went together, we're just looking for a problem. That motor should run.
Yes I agree if they are both 32.Everything I'm reading now is that the vin isn't definite,but what matters is the pcm being 3 or 4 plug and I have one of each.
But thats not definite either so I guess I'm gonna check before I spend another bunch of time trying to fix it if it's different.
Well look at it this way, time spent pulling an oil pan and finding out you have to pull the motor anyway, and more money spent on rebuilding a motor verses time spent putting in the other pcm. People do it all the time. As I looked at my Chevy, It really doesn't look that hard. You know that it ran that motor. I think you need to just check over everything, especially the ground wires, see if there is anything your missing between the two to make it run, sleep on it and decide what to do next. You never did tell me for sure if you didn't have spark, I assumed not. And you know this 2002 motor was running just fine. And you drove the 2003 so all of that system was working? You got me into this so I will do everything I can to help. And don't worry about my time, I just like to do this and help. I have one more source I can check, may take a day,..Let me know
OK thanks again. But no I was driving the 02 and bought the 03 and switched the motor from the 02 to the 03.Gonna be off it for a couple days anyway.Grandson is having surgery.When I get back I'll drop pan and be sure.Once more I sure appreciate your help.
Just curious did it ever run?
Well,I wound up rebuilding the motor out of the 03,but I can tell you for sure now that if the PCM has 3 plugs the motor will have a 16 tooth tone ring and 4 plugs is a 32 tooth ring.Everything will fit,but will not fire until you match tone rings.
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