Something tells me this engine timing isn't quiet right...
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Something tells me this engine timing isn't quiet right...
2000 Dodge RAM 1500 5.9L V8 Magnum...
The timing adjusting itself all over the place during idle isn't normal, right?
Could this be a bad ECM? The only other thing I can think of would be a bad distributor... perhaps the cam position sensor? But, the timing evens out perfectly when RPMs are over 1500 or so. It's only at idle, accelerating through 1st gear, and when under load (going uphill, etc.) that it does this (which seems to be the cause of the engine stumbling through acceleration)...
I just had the engine completely re-manufactured, and so it has a brand new timing chain in it...
Any input would be greatly appreciated!
The timing adjusting itself all over the place during idle isn't normal, right?
Could this be a bad ECM? The only other thing I can think of would be a bad distributor... perhaps the cam position sensor? But, the timing evens out perfectly when RPMs are over 1500 or so. It's only at idle, accelerating through 1st gear, and when under load (going uphill, etc.) that it does this (which seems to be the cause of the engine stumbling through acceleration)...
I just had the engine completely re-manufactured, and so it has a brand new timing chain in it...
Any input would be greatly appreciated!
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Shouldn't be the plenum. The motor has about 500 miles on it. New gaskets, heads, pistons, lower block, lifters, etc., the works.
Cold, hot.. doesn't matter. It isn't the O2 sensors. I replaced both of them just to be sure.
It does have a Compcam camshaft in it, but it is the least-aggressive one they make. Nearly the same as factory. It shouldn't be causing this sort of thing.
Cold, hot.. doesn't matter. It isn't the O2 sensors. I replaced both of them just to be sure.
It does have a Compcam camshaft in it, but it is the least-aggressive one they make. Nearly the same as factory. It shouldn't be causing this sort of thing.
Champion
Joined: Aug 2010
Posts: 2,697
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From: Cape Carteret NC
It's jumping, its not that its steady.. rule out the cam..
The o2's are out if it does it in open loop..
Check your IAT.. unplug it, and see if it jumps like that.. do the same (not at same time) with coolant sensor.. engine should run off tables at that point.. see if it continues.. if it does, there are two other things to look at..
The o2's are out if it does it in open loop..
Check your IAT.. unplug it, and see if it jumps like that.. do the same (not at same time) with coolant sensor.. engine should run off tables at that point.. see if it continues.. if it does, there are two other things to look at..
Thread Starter
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Registered User
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It's jumping, its not that its steady.. rule out the cam..
The o2's are out if it does it in open loop..
Check your IAT.. unplug it, and see if it jumps like that.. do the same (not at same time) with coolant sensor.. engine should run off tables at that point.. see if it continues.. if it does, there are two other things to look at..
The o2's are out if it does it in open loop..
Check your IAT.. unplug it, and see if it jumps like that.. do the same (not at same time) with coolant sensor.. engine should run off tables at that point.. see if it continues.. if it does, there are two other things to look at..
Still jumps and has engine sinusoidal hesitation under load or acceleration through 1st with the IAT unplugged.
With the coolant sensor unplugged, the engine didn't want to start for some time, and there was quite the ozone/sulfur smell coming through the vents when the engine did start. Timing still jumped around, but I didn't want to drive the truck much with things behaving as they were. Wasn't able to test uphill hesitation.
