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Discussion Starter #1
Hello, I have this issue and I wish someone could give me an advice.

1. The engine stops at the parking. Restarted but very unstable RPM and stops soon. After a few try, zero RPM, no start at all, cranking is OK.
2. Schrader valve on the fuel line at the engine has no pressure now.
3. Fuel Pump relay and fuse should be OK, and fuel pump is making zzzz noise for a few sec when the key turns on. I'm not sure if the fuel pump is OK>
4. Gas meter shows 1/4.

I'm wondering what procedure I should do next.

Thank you very much in advance. Have a nice weekend, guys. :smile
 

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Discussion Starter #3
Sorry for too many posts at once...

I realized that I have not changed Fuel Filter last 10 years (or 100000 miles). It can be clogged?
BTW, I changed spark plugs recently, and they look OK (gray), except a few were black.

No error code with ODB2 and Movi Pro.
 

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It could be your fuel pump or fuel pressure regulator which is built into the fuel filter. One think I would try is adding another 5 gallons of fuel and checking to see if problem goes away. If that resolved it then it's your fuel pressure regulatir/filter. If it doesn't then it's the pump. When I had this problem on my 02 c320 wagon at 150k miles, I replaced both the FPR/filter and pump. It turned out to be be a bad pump but I felt better replacing both at the same time. I think I spent $100 total in parts.
 

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Discussion Starter #5
Thank you so much!
I will buy filter and pump from amazon today, and replace the filter first. If it is a filter (hopefully), I may return the pump.
My C320 is 180000 miles. Too many electronics failures (door lock etc), but car still runs very well.
 

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Discussion Starter #6
Well, C320 engine still doesn't start after changing fuel filter, fuel pump, and CPS. Battery is recharged, and the motor cranks.
Any Fuse that I should check?

Please someone help!
 

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Check for fuel pressure when cranking.
If fuel pressure is ok,maybe bad fuel, drain and refill with new gas.
Check for spark.
If no spark,check all ignition system wiring and battery terminal connections are clean and tight.Also check the engine ground connection is good.
Good luck.
 

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Discussion Starter #8
Thank you for the advice.

Fuel Pressure is fine.
I just removed one plug and checked spark. It looks like plug sparks OK. When trying to start engine it sparks every second.
I added 1 gallon of Gas, but it didn't change. The fuel meter is about 1/4.

Any other idea?
I would really appreciate it for any advice!

Check for fuel pressure when cranking.
If fuel pressure is ok,maybe bad fuel, drain and refill with new gas.
Check for spark.
If no spark,check all ignition wiring and battery terminal connections are clean and tight.Also check the engine ground connection is good.
Good luck.
 

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How I can drain Gas from the fuel line?
You could connect a hose to the schrader valve if you have the right fitting, or otherwise disconnect the fuel line near the driver's side valve cover ,,17mm spanner. and then connect a suitable hose to it to feed into a bucket. Be careful.

If you are sure you have good fuel and good spark and it still wont run the next thing to check is cylinder compression.
 

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Discussion Starter #12
You could connect a hose to the schrader valve if you have the right fitting, or otherwise disconnect the fuel line near the driver's side valve cover ,,17mm spanner. and then connect a suitable hose to it to feed into a bucket. Be careful.

If you are sure you have good fuel and good spark and it still wont run the next thing to check is cylinder compression.
Thanks a lot. I found 17mm fuel line connector, and I'll drain gas from there, but I honestly think the gas should be OK, because my wife told me she only got Gas from Costco last few months.

Is it possible that security system error or other electrical issue?
 

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Best of my limited knowledge,if it was a security system or electrical issue you would not be getting a spark and/or fuel delivery.
The fact that you have these means the problem is either water in the fuel/bad fuel or a compression problem.
Unless all fuel injectors stop working somehow ?
Maybe you could remove some spark plugs after some cranking and see if they are wet with fuel to check on this.
 

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Discussion Starter #14
Best of my limited knowledge,if it was a security system or electrical issue you would not be getting a spark and/or fuel delivery.
The fact that you have these means the problem is either water in the fuel/bad fuel or a compression problem.
Unless all fuel injectors stop working somehow ?
Maybe you could remove some spark plugs after some cranking and see if they are wet with fuel to check on this.
Actually when I removed one spark plug after cranking, the plug was wet. Is it normal?
 

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Yes, that tells you that fuel is being injected into the chamber but is not igniting,which is why the engine does not run.
If you have spark and compression then the only thing left to be at fault is the fuel quality.
 

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Discussion Starter #16
Yes, that tells you that fuel is being injected into the chamber but is not igniting,which is why the engine does not run.
If you have spark and compression then the only thing left to be at fault is the fuel quality.
Ok, I'll drain fuel from 17mm connector tomorrow. Thanks a lot!
 

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Good luck.
But if your CPS is not plugged in then that will be the problem. I think it should 'click' in to place.
Don't drain fuel unless you are sure the CPS is installed properly.
 

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Discussion Starter #19
Good luck.
But if your CPS is not plugged in then that will be the problem. I think it should 'click' in to place.
Don't drain fuel unless you are sure the CPS is installed properly.
Benzyle, thank you so much! I drained fuel line about one gallon to check the gas quality just turning the key on an off, and the gas "looks" OK, so I reattached the harness to the CPS, and FINALLY the engine started.

But I have another issue, sigh... The idling is very rough below 1500, when the engine runs above 1500, runs just fine. Should I drain all the gas from the tank and the fuel line? I see random misfire and some other misfire code on ODB.
 
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