Chevy Cobalt Forum banner

1 - 14 of 14 Posts

·
Registered
2006 Chevy Cobalt LS 2.2 L61 300,000 miles and still going
Joined
·
10 Posts
Discussion Starter · #1 ·
So I'm new to this so I'll try to make this as quick and painless as possible. My 06 cobalt 2.2 just cut out on me the other day . Not getting her to fire up . So I started the normal trouble shooting. Scan for codes nothing but 02 sensor. Went and crawled under to check everything under by the fuel tank. Was playing with the lines and plugs and squeezed the top line into the fuel filter ,had my ol lady crank it and it fired right up no issue until I let go of the line and it died. I'm completely puzzled . I believe it's the return line so I don't know if I should buy a new pump or filter or both just for the hell of it . I replaced the sending until pump and filter in June of 2019 so I'm kind of stumped what to do???
I have never had anything like this happen before. Any suggestions or input would be greatly appreciated.
 

·
Registered
Joined
·
494 Posts
By the lines and plug, do you mean the wiring harness? It is not uncommon to have issues with the wiring that goes to the fuel pump. Actually many times the new fuel pump will come with a new harness, also sometimes called a pig tail connector. Usually it is splicers into the wiring using weather tight butt connectors. The connectors are supposed to be heated so the heat shrink will melt around the wiring sealing out corrosion and also keeping the wires securely connected into the butt connectors so they can’t pull out with vibration. Sometimes people will forget to seal the connector and it can cause the wire end that is stripped to fit into the connector to corrode or pull out. Also sometimes the connector that goes onto the fuel pump may be faulty from being pulled on when removing or installing the new fuel pump. Especially if the connector wasn’t replaced with the fuel pump. The wires can be pulled out of the plastic connector. They may still be stuck in the connector but not set deep enough into it and over time will loose connection.

Anyways that’s a common issue I have run into over the years. I have a lot of Cobalts and other GM cars from this era come in to the shop and have inoperative fuel gauges a lot of times. In fact the most recent Cobalt I had at the shop was last week and it has the issue of the inoperative fuel gauge.
 

·
Registered
2006 Chevy Cobalt LS 2.2 L61 300,000 miles and still going
Joined
·
10 Posts
Discussion Starter · #3 ·
By the lines and plug, do you mean the wiring harness? It is not uncommon to have issues with the wiring that goes to the fuel pump. Actually many times the new fuel pump will come with a new harness, also sometimes called a pig tail connector. Usually it is splicers into the wiring using weather tight butt connectors. The connectors are supposed to be heated so the heat shrink will melt around the wiring sealing out corrosion and also keeping the wires securely connected into the butt connectors so they can’t pull out with vibration. Sometimes people will forget to seal the connector and it can cause the wire end that is stripped to fit into the connector to corrode or pull out. Also sometimes the connector that goes onto the fuel pump may be faulty from being pulled on when removing or installing the new fuel pump. Especially if the connector wasn’t replaced with the fuel pump. The wires can be pulled out of the plastic connector. They may still be stuck in the connector but not set deep enough into it and over time will loose connection.

Anyways that’s a common issue I have run into over the years. I have a lot of Cobalts and other GM cars from this era come in to the shop and have inoperative fuel gauges a lot of times. In fact the most recent Cobalt I had at the shop was last week and it has the issue of the inoperative fuel gauge.
No sir. I was referring it the fuel lines on the fuel filter. When I pinched off the top fuel line to the fuel filter the car will run . But as soon as I let go of the fuel line and let it flow as normal it will stall out. I just don't want to buy parts I don't need. I have been without my car since I posted this because the car is 100 miles away from me at the moment.
 

·
Registered
Joined
·
494 Posts
So it sounds as if you’re saying you have pinched the fuel line to block flow. And in doing so the car will now run with the line pinched. It sounds like you may have a bad fuel pressure regulator. One of the lines supplies fuel to the engine. The other line is a return line. The fuel pressure regulator must be stuck open and is allowing the fuel to return and not allow enough fuel pressure to the injectors. Unfortunately the fuel pressure regulator is integrated with the fuel pump assembly. The fix will likely be to replace the pump assembly. Also make sure and change the fuel filter at the same time. If you haven’t checked the fuel pressure, this would be step one in checking the fuel system.

At least with what you’re saying is happening it really sounds like a bad fuel pressure regulator that is integrated into the the fuel pump assembly. Maybe there is some odd chance that the fuel filter is causing this, but fairly unlikely with the symptoms and things you have done to get it to run.

The non steel fuel lines are not made to be squeezed or pinched. So you may have actually damaged them doing that. I wouldn’t be surprised if you may need to replace them as they may split open now.
 

·
Registered
2006 Chevy Cobalt LS 2.2 L61 300,000 miles and still going
Joined
·
10 Posts
Discussion Starter · #5 ·
So it sounds as if you’re saying you have pinched the fuel line to block flow. And in doing so the car will now run with the line pinched. It sounds like you may have a bad fuel pressure regulator. One of the lines supplies fuel to the engine. The other line is a return line. The fuel pressure regulator must be stuck open and is allowing the fuel to return and not allow enough fuel pressure to the injectors. Unfortunately the fuel pressure regulator is integrated with the fuel pump assembly. The fix will likely be to replace the pump assembly. Also make sure and change the fuel filter at the same time. If you haven’t checked the fuel pressure, this would be step one in checking the fuel system.

At least with what you’re saying is happening it really sounds like a bad fuel pressure regulator that is integrated into the the fuel pump assembly. Maybe there is some odd chance that the fuel filter is causing this, but fairly unlikely with the symptoms and things you have done to get it to run.

The non steel fuel lines are not made to be squeezed or pinched. So you may have actually damaged them doing that. I wouldn’t be surprised if you may need to replace them as they may split open now.
Thank you I was assuming it was the whole sending until. Now I have confirmed that I will get that ordered also .
 

·
Say What again!
Joined
·
6,291 Posts
So it sounds as if you’re saying you have pinched the fuel line to block flow. And in doing so the car will now run with the line pinched. It sounds like you may have a bad fuel pressure regulator. One of the lines supplies fuel to the engine. The other line is a return line. The fuel pressure regulator must be stuck open and is allowing the fuel to return and not allow enough fuel pressure to the injectors. Unfortunately the fuel pressure regulator is integrated with the fuel pump assembly. The fix will likely be to replace the pump assembly. Also make sure and change the fuel filter at the same time. If you haven’t checked the fuel pressure, this would be step one in checking the fuel system.

At least with what you’re saying is happening it really sounds like a bad fuel pressure regulator that is integrated into the the fuel pump assembly. Maybe there is some odd chance that the fuel filter is causing this, but fairly unlikely with the symptoms and things you have done to get it to run.

The non steel fuel lines are not made to be squeezed or pinched. So you may have actually damaged them doing that. I wouldn’t be surprised if you may need to replace them as they may split open now.
Thinking about that, it's a little weird they had the fuel pressure regulator at the pump like newer cars now...but still kept the return line. Having your regulator there allows you to remove the need for a return line, since you can send the right amount of fuel to the rail and thus not need a return. Interesting, must've been like an intermediate step between return-style fuel systems with the regulator at the rail, and returnless-style systems with the regulator in the tank/at the pump.
 

·
Registered
2006 Chevy Cobalt LS 2.2 L61 300,000 miles and still going
Joined
·
10 Posts
Discussion Starter · #7 ·
Thinking about that, it's a little weird they had the fuel pressure regulator at the pump like newer cars now...but still kept the return line. Having your regulator there allows you to remove the need for a return line, since you can send the right amount of fuel to the rail and thus not need a return. Interesting, must've been like an intermediate step between return-style fuel systems with the regulator at the rail, and returnless-style systems with the regulator in the tank/at the pump.
What's even stranger. There is no return line up front in the engine compartment that I saw. I could be wrong but I have never seen any other fuel line but the main coming up to the fuel rail .
 

·
Say What again!
Joined
·
6,291 Posts
You know what - the second line isn't a return line - it's the vapor line. So it is a "normal" returnless system.

 

·
Registered
2006 Chevy Cobalt LS 2.2 L61 300,000 miles and still going
Joined
·
10 Posts
Discussion Starter · #9 ·
You know what - the second line isn't a return line - it's the vapor line. So it is a "normal" returnless system.

Thank you for the correction 👍 .
 

·
Say What again!
Joined
·
6,291 Posts
Of course! Needed to check after you mentioned there was nothing up front.

I did the fuel lines on my brother's '01 Century last summer (despite telling him I had no interest in doing them - saved him probably $700, but I did not have an enjoyable time doing them - who knew plastic could rust to metal!) and that was the standard return setup: feed, return (which was leaking in 2 or 3 spots) and vapor.
 

·
Registered
Joined
·
494 Posts
So could that mean that the vapor line is causing some sort of issue for him? Why would pinching off flow allow the car to run. I have also seen this set up on some Ford vehicles. Could that actually be a problem with the EVAP system if that line is a vapor line?

I would still assume the fuel pump is ready to take a dump though. Have you been able to check fuel pressure.
 

·
Registered
2006 Chevy Cobalt LS 2.2 L61 300,000 miles and still going
Joined
·
10 Posts
Discussion Starter · #12 ·
I will be going out to the car in 2 days. I have a scanner and fuel pressure tester. Right along with the tools to fix her and get her home .If I can't fix her there I will tow her home.
 

·
Say What again!
Joined
·
6,291 Posts
Best of luck!
 
1 - 14 of 14 Posts
Top