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Don't assume that just because some parts were replaced, that those parts are good. You can get bad parts new, right out of the box.

Does it run smooth at higher revs, but just has no power in drive? I wonder if ignition timing is late (retarded). These vans have a problem with flex plates cracking. Any weird noises? They crack around the bolt circle at the crankshaft, and the outside can shift enough to run poorly, but still run. Normally the crank sensor signal would be off enough to not allow the van to start, but in 2005 the wiring was changed along with some computer stuff. The change allows the engine to run with just one sensor (cam or crank) if the other fails (before this, both sensors needed to work for the engine to run). This is basically just like retarding the distributor on an older engine.

You can check it with a timing light, if you make your own timing marks on the crank pulley and something stationary with, say, #2 cylinder at TDC (front far left spark plug when looking at engine). Pull the spark plug out and use a piece of solder in the plug hole to feel when that piston is at the top, rotating engine with a wrench/bar with the key OFF. Putting the inductive lead on the #2 wire, you can then see timing on the running engine.

Thoroughly check over the fuel system and wiring first, because it's easiest. Could just be dirty fuel injectors, or maybe a vacuum leak. Since 2005 had a lot of electrical changes, they seem to have the most electrical problems (which would cause me to stay away from a 2005). Anyway, best of luck!
 

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2005 Dodge Caravan C/V
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Suggest you check oxygen sensor function in a scan tool with realtime plotting.
A gutted cat or dead downstream O2 sensor shouldn't affect how the van runs. The downstream sensor pretty much just tells the computer if the cat is present and working.
 

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A gutted cat or dead downstream O2 sensor shouldn't affect how the van runs. The downstream sensor pretty much just tells the computer if the cat is present and working.
Correct.

O2 sensors are not used during open loop to begin with.

Forget about O2 sensors for now. You can disconnect the O2 sensor and you might never know those sensors are disconnected (other than a CEL).
 

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take off intake manifold and check the harness for fuel injectors, had that problem with my 04, no codes, no power, then a single cylinder misfire. All the wires were exposed and touching
 

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This is a 2005 van. The fuel injector harness problem doesn't apply, as the wiring harness was changed to run it in from the drivebelt side.
 

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This is a 2005 van. The fuel injector harness problem doesn't apply, as the wiring harness was changed to run it in from the drivebelt side.
Hey, does anybody know if a 2005 and later FI harness could easily be fitted to my 2002? Perhaps that is the recommendation for the 'melt down'....
Upgrade

Better than a tin foil hat.
Plug and play? (same connectors)
 

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No, the harness itself was changed in 2005 to run it from the passenger side. A LOT of the wiring in the front of the van was changed, which is why there are a lot more electrical problems on 2005's (first year of a new change). I thought of this same thing when I fixed my friend's van many years ago. Just proves that great minds think alike. :)

Best fix might be to cut some plugs off of a van to build an extension harness, and reroute the harness over the top of the crossover pipe over the engine and heat shield it. I'll look into it closer when I do my engine swap.
 

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Josh, if your friend has a car lot, he should have unlimited access to Carfax reports. Before you dump lots of time and money into this thing, it would be smart to get one.

In the past of bought them on ebay for $3 to $5.
 

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Discussion Starter #34
I made headway! Runs better and actually drives when the crankshaft sensor is unplugged. So, either bad sensor or cracked flexplate. No ticks or any signs of it being broken though..hopeful that it's just the sensor, but unsure how a sensor could send false readings and throw timing that far off
 

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Cheap discount parts store sensors often go bad in a year or don't perform correctly. I used a crank sensor from NAPA once to fix a Jeep Grand Cherokee, after the sensor had been previously replaced by a repair shop. They are located under the exhaust manifold/crossover pipe and are subjected to a lot of heat. It has a coil in it, so that is why they go bad when exposed to high heat for a long time. The crank sensors on these 4th gen vans just push right into a hole on the bellhousing, with no need for a paper spacer. Hopefully you just need a new crank sensor (Mopar or NAPA).
 

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Discussion Starter #36
Well I put a new sensor in and unbolted the torque converter. No signs of cracked flexplate and it still runs horribly with it plugged in. I'm so ready to burn this van. Not ready to pull the transmission to find out there's no cracks in the flexplate. Might go get a junk yard pcm and throw in and see what happens. Obviously something is throwing the timing out of whack when it's plugged in.
 

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Crankshaft Position Sensor activates the ASD relay. Without a signal to the ASD relay engine shouldn't start. It could be that someone bypassed the ASD relay.

Even with a bypassed ASD relay, engine shouldn't start.

Are you sure you are looking at the crankshaft sensor?
 

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Discussion Starter #40
Crankshaft Position Sensor activates the ASD relay. Without a signal to the ASD relay engine shouldn't start. It could be that someone bypassed the ASD relay.

Even with a bypassed ASD relay, engine shouldn't start.

Are you sure you are looking at the crankshaft sensor?
2005s will run on either missing camshaft sensor or crankshaft sensor signal. It goes off the other sensor.. This van runs way better with either off. Runs like total crap with both plugged in. And both are New. Something is throwing the timing way off. Everything but the pcm is New in this turd. That's next.
 
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