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Discussion Starter #1
Hey guys, this might be a long shot, but I’m hoping someone here will have some suggestions.

I own a 2003 Dodge Ram 5.2L

When purchased it was running a bit rough, so I went over most of the standard items (spark plugs, cap & rotor etc) and afterwards it ran great. I took it on a 5000 mile trip with no problems, but as I got it home it was running rough and then would not start. Moving the cap & rotor will get it to fire up, but it’ll stall out almost immediately. If I adjust the cap & rotor I can keep it running, but only with the throttle slightly open. When it’s running, it sounds fine.

With lots of googling and trouble shooting I found that they can have a faulty intake plenum gasket. I verified there was oil in my intake, and replace the intake plenum with the Hughes Engine kit - It comes with an aluminum plate instead of the steel one, with all new gaskets etc. While I was in there, I changed the intake gaskets, thermostat, coolant bypass hose - any related items I could think of.

It seemed the engine sounds slightly different (better) but it will still stall with the same symptoms. I hooked up an OBD that shows live read-outs, and found that the timing is advanced to around +34, and when it stalls out, it stalls around +22. I’ve changed the cam and crank position sensor with no change. I’ve checked for vac leaks with some carb cleaner and haven’t found any.

The ADS relay was swapped with the AC Compressor relay to rule that out also.

It seems to me as though it’s timing related, although I’m not certain. The vehicle seems to change timing advance enough to kill itself but I can’t figure out what to check next. The final clue potentially is that no matter what the rad fan runs full blast. I’m not sure they’re related but it seems odd to me.

Items on the way are spark plugs (again), coolant temperature sensor, gas cap, idle air control valve, and throttle position sensor.

I’m wondering if anyone has had similar issues or could shed some light on the problem. Thanks in advance!
 

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Hey guys, this might be a long shot, but I’m hoping someone here will have some suggestions.

I own a 2003 Dodge Ram 5.2L

When purchased it was running a bit rough, so I went over most of the standard items (spark plugs, cap & rotor etc) and afterwards it ran great. I took it on a 5000 mile trip with no problems, but as I got it home it was running rough and then would not start. Moving the cap & rotor will get it to fire up, but it’ll stall out almost immediately. If I adjust the cap & rotor I can keep it running, but only with the throttle slightly open. When it’s running, it sounds fine.

With lots of googling and trouble shooting I found that they can have a faulty intake plenum gasket. I verified there was oil in my intake, and replace the intake plenum with the Hughes Engine kit - It comes with an aluminum plate instead of the steel one, with all new gaskets etc. While I was in there, I changed the intake gaskets, thermostat, coolant bypass hose - any related items I could think of.

It seemed the engine sounds slightly different (better) but it will still stall with the same symptoms. I hooked up an OBD that shows live read-outs, and found that the timing is advanced to around +34, and when it stalls out, it stalls around +22. I’ve changed the cam and crank position sensor with no change. I’ve checked for vac leaks with some carb cleaner and haven’t found any.

The ADS relay was swapped with the AC Compressor relay to rule that out also.

It seems to me as though it’s timing related, although I’m not certain. The vehicle seems to change timing advance enough to kill itself but I can’t figure out what to check next. The final clue potentially is that no matter what the rad fan runs full blast. I’m not sure they’re related but it seems odd to me.

Items on the way are spark plugs (again), coolant temperature sensor, gas cap, idle air control valve, and throttle position sensor.

I’m wondering if anyone has had similar issues or could shed some light on the problem. Thanks in advance!
When you say "Moving the cap & rotor" and "I adjust the cap & rotor", are you talking about loosening the hold-down bolt and turning the distributor? If so, that's a BAD move. This does not adjust ignition timing. Doing so adjusts the fuel injector synchronization. It has to be accurately set within a couple of degrees, or it will run very poorly, backfire or not start. If you did this, you need to set it back to zero BTC with a diagnostic tool, or have a mechanic do it. You cannot adjust the ignition timing on these engines.
 

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Have you checked for play in the timing chain? Also, agree about the distributor, the computer determines the timing. There should be a little notch on the top edge of the distributor housing that lines up the rotor with number one TDC as a rough guide to sync the injector to the spark, then the scan tool as noted previous post talks about.
 
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Is there a vacuum advance on the distributor or had they done away with it by 03? I agree that it's got to be timing related.
 

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If you have a 2003 Ram with a 5.2 l you have a very rare truck. Would be interested to know if this is really what you have.

3.7 l v6, 4.7 l v8, 5.7l v8, 5.9l v8 and if you have 2500/3500 5.9l s6 diesel and 8.0l v10

I have really wanted to get one of each.

Also if you are moving the cap you may have screwed up your firing order also. Worth the check.
 

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Devildodge - good point. The 5.2L was not available in 2003 - only the engines you mentioned. I'll bet he has a 5.9L (gas) or someone transplanted a 5.2L.
 

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I would assume it’s a Ram van, not a Ram pickup as the van still had the 5.2 engine in 2003.
 

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Discussion Starter #9
When you say "Moving the cap & rotor" and "I adjust the cap & rotor", are you talking about loosening the hold-down bolt and turning the distributor? If so, that's a BAD move. This does not adjust ignition timing. Doing so adjusts the fuel injector synchronization. It has to be accurately set within a couple of degrees, or it will run very poorly, backfire or not start. If you did this, you need to set it back to zero BTC with a diagnostic tool, or have a mechanic do it. You cannot adjust the ignition timing on these engines.
We have turned the distributor but have had a mechanic & a diagnostic tool to set it back, with no fix.
 

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Discussion Starter #10
If you have a 2003 Ram with a 5.2 l you have a very rare truck. Would be interested to know if this is really what you have.

3.7 l v6, 4.7 l v8, 5.7l v8, 5.9l v8 and if you have 2500/3500 5.9l s6 diesel and 8.0l v10

I have really wanted to get one of each.

Also if you are moving the cap you may have screwed up your firing order also. Worth the check.
Yeah, my bad - it is the Ram Van with the 5.2.
 

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Theres a lot of spark in these so they need good ign wires and they have to be routed correctly so they dont crossfire. ( correct routing looks like crap..)
Have you changed the plugs after you fixed the plenum leak?
 

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Diagnose first. How do the old spark plug tips look? Tip color is an indication of combustion burn. White may be lean and black may be rich.
You should have a nice blue, white spark out of the coil. If it is orange or yellow, the voltage is low and the coil may be failing. If the coil is mounted at the right, front exhaust manifold, the heat can eventually kill the coil after some time.
Use the correct OEM Champion Copper Plus RC12LC4 spark plugs for best results.
 

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Have you checked for play in the timing chain? Also, agree about the distributor, the computer determines the timing. There should be a little notch on the top edge of the distributor housing that lines up the rotor with number one TDC as a rough guide to sync the injector to the spark, then the scan tool as noted previous post talks about.
Suspect a jumped timing chain, a tooth or two. I have seen many engines run relatively well with a stretched chain which didn't jump. Many times if the chain jumps, you may notice the engine cranking speeds go up as the compression decreases.
 

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It is less likely the chain has jumped as these run a tensioneron the chain. But it is still something you should check.
 

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These engines are noted for wear to the timing chain and its guide, and there is a TSB for a re-design. I had it done in 2004.
 

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How many miles?
A quick test for timing chain slack is to have a helper rotate the crankshaft slightly CW and CCW with the distributor cap off. See about how many degrees that the crank has to turn before the slack is taken up and the rotor moves.
 

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Also, the bushing at the bottom of the distributor shaft can wear and cause stalling. When my brother owned my truck, this happened before 50K miles while accelerating on an on-ramp.
 

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Yes, the bushing on the oil pump drive (auxiliary) shaft could wear and timing would jump around . The distributor has to be removed and the gear down in there should not rock around at all. If it does move around, then the bushing is likely worn. You won't see or feel this play with the distributor in place. It has to come out. This was covered under TSB # 18-08-93A. A special tool installs and reams the new bushing as the tool is removed. The majority of the problem was resolved by 1993, but the bushing was still a wear item:
TSB 18-08-93 Rev. A (at http://dodgeram.info/tsb/1993/18-08-93.htm )
 

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Discussion Starter #20
Hey everyone,

Thanks for all of the suggestions! We've been trying to troubleshoot like crazy but still not much luck...

When it runs it sounds great, but we had hooked a timing light up, which seemed to show us the timing was changing inconsistently. It seems like the pcm is advancing timing until the van dies.
 
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