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Gas leak in 2005 Caravan

It sounds like you have to replace the pump in any event, but my guess is the reason you see no gas coming out of that line during cranking is b/c the engine computer isn’t detecting engine rotation. If no engine rotation is detected, it won’t turn on the fuel pump. You engine probably uses a crank position sensor to detect engine rotation. A fault in that part would explain both the no gas during cranking and the lack of spark.

fyi, one method suggested here to test if the problem is lack of fuel or lack of spark is to spray a little starter fluid into the intake manifold and see if it briefly starts then. If it briefly runs then stalls, you know you have spark but no fuel.

Re the fuel pump job. Gasoline is very dangerous, so be sure to take all common sense precautions, for example a big fire extinguisher on hand, eliminate all ignition sources (like a nearby gas hot water heater) and avoid doing the job near structures ( house, garage, etc) that might catch on fire. Best of luck.

The new fuel pump is now installed. Still won’t start, as I suspected would happen. At least there is no more gas leak. On to the electrical, though at this point probably over my head.

I have found the minivan forum at allpar.com to be very helpful when I had questions about my Chrysler Corp. minivans. Posting there may yield some worthy suggestions.

Shanonia, another one is dodgetalk, however, I’ve had a bit of an issue with that. Found a post with the same problem, and one of the responders was very helpful, to include pictures of what/how to test. Unfortunately the forum will not allow me to see the pics. Says I don’t have permission. Wtf?

Did you join and sign in to the forum? Many require that to have full viewing privileges.

I think I’m with George on this. If it just went dead and no spark, I would suspect the crank sensor first. It’ll cause a total loss of ignition because the engine rotation isn’t being detected. Good thing to put the pump in anyway. I had one come apart on the highway so it does happen.

Best way to confirm a bad pump if you don’t hear it running is with a fuel system tester (about $50 though for a cheap one). Normally a pump will run for a couple seconds when the key is in run and should continue to run while its being cranked. But again if the crank sensor is gone, the computer wouldn’t know its being cranked, like George said.

Yeah, I joined the forum. That’s why it was peculiar I couldn’t view the attachments.

This has taken an odd turn. I gave up and put it in the shop. they just told me the EGR valve is bad, which I had replaced about a week before it went dead. I haven’t found anywhere that says a bad EGR will kill the power completely. They said there is a 5V reference that wasn’t detected, and the EGR is “connected” to everything else like the camshaft sensor… Without the reference voltage it wont run. they disconnected the EGR and it started up. I’m wondering if it ids a bad connection somewhere and not the actual EGR valve.

The PCM sends a 5 volt power supply to the sensors, if one of the sensors shorts the 5 volt feed none of the sensors can function. It seems that the EGR valve position sensor was shorted.

Can I just ground the 5V reference? I’m going to replace the EGR valve, but likely won’t get to it for at least a week or two. Meanwhile, I’m driving around with a failed inspection sticker.

Can I just ground the 5V reference?

What Nevada means is the engine computer provides a precision 5 volt reference to power a bevy of sensors. They all require this precision voltage reference from the computer. So there’s a single wire from the computer which splits into a half dozen wires, each going to a different sensor. For those sensors to work accurately they all need a precision voltage. The battery voltage changes all the time depending on if the engine is running and how charged up it is , so the engine designers can’t use that to power the sensors. It has to come from the computer.

If one of the sensors (such as the egr) inappropriately connects the 5 volt reference directly to ground, then all the other 5 sensors are connected to ground. Why? Because it is the same wire from the pcm, so that shorts the other sensor’s power to ground too, so none of them work. As you might expect, no sensors working, no good.

I'm wondering if it ids a bad connection somewhere and not the actual EGR valve.

The EGR function is very complicated on newer cars. In days of yore the EGR was mostly either on or off, controlled by engine vacuum and maybe the vacuum control was in series with a coolant temperature activated vacuum switch. But newer cars the amount of EGR needed to keep within emissions limits (and to keep the internal engine temperatures safe) varies continuously, depending on the driving situation. So EGR has to be electronically sensed and controlled. To determine if the short is the EGR or the wiring harness, disconnect the EGR from the wiring harness. Measure the resistance to ground on the 5 volt reference pin on the EGR itself. If it reads a very low resistance, like 1 ohms or less, the new EGR is likely the problem. If so, the place that sold it to you may replace it for free, since you just bought it.