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knownothingmags
04-26-2011, 12:17 AM
car wont start,

car is a 2006 Chevy Cobalt SS Supercharged.

changed the fuel filter.
dummy proof has quick disconnect on one side and two other inlets that are coming out the other side. both different sizes so you cant hook them up wrong.

got the new fuel filter in car, wont start.

the way the forums and mechanics told to depressurize the system is as follows:

pop hood go to fuse box pull the fuel relay out, start car, let it it run till it chugs itself out, then shut car off and take keys out of ignition, now safe to put relay back in, now procceed to putting new filter in.

question is why wont car start?
is the fuel pump gone/dead?

INFO:
i did not mess with any wiring while doing this replacement, since it does not require it.

help please,

thankyou,
knownothingmags.

Frizzle Fry
04-26-2011, 12:55 AM
car wont start,

car is a 2006 Chevy Cobalt SS Supercharged.

changed the fuel filter.
dummy proof has quick disconnect on one side and two other inlets that are coming out the other side. both different sizes so you cant hook them up wrong.

got the new fuel filter in car, wont start.

the way the forums and mechanics told to depressurize the system is as follows:

pop hood go to fuse box pull the fuel relay out, start car, let it it run till it chugs itself out, then shut car off and take keys out of ignition, now safe to put relay back in, now procceed to putting new filter in.

question is why wont car start?
is the fuel pump gone/dead?

INFO:
i did not mess with any wiring while doing this replacement, since it does not require it.

help please,

thankyou,
knownothingmags.

When you say "doesn't start" do you mean it won't turn over at all, or it's turning over but not starting? Any clicking noises when you try to start it? If it is cranking, do you hear any grinding or scraping? Are the cabin and dash lights coming on, and if so, are all of them working?

About 95% of the time a car refuses to start after an oil change because you or the tech left a light or the radio on and you killed the battery. Maybe 4% is jarring something loose while you're doing it (anything from a ground for the radio/ac/LED which are keyed to the immobilizer system, to the battery itself). That last 1% is actual "problems".

If I were you I'd check every connection to the ignition system and the starter itself - things like this are the reason I hate modern vehicles; there are far too many failsafes programmed into too many onboard computers. 90% of the time a "check engine" light has to do with your car "getting used to" having full tires or fresh oil or a new cabin filter, but the auto industry makes a killing charging you $80 - $100 to check if anything is wrong, knowing full well that it takes most cars 5+ starts and 100+ miles to recognize that this is "just how it runs". Cars can also be "trained" to accept all sorts of problems that will shorten its lifespan.

Dark Side
04-26-2011, 04:54 AM
Did you prime you fuel lines after replacing the filter?

Pneumagger
04-26-2011, 07:59 AM
Do you hear the fuel pump kick on when you turn the key to the run position?
why not try to measure the fuel line pressure (easy)?

knownothingmags
04-26-2011, 09:03 AM
frizzy- attempts to turn over but wont start, all lights are on. there is a possible fuel filter recall.
no scraping.
everyone else- i can not hear the fuel pump kick on. how would i prime the fuel lines after i changed to a new filter?

Pneumagger
04-26-2011, 09:58 AM
It's air, spark, or fuel.

Squirt starting fluid into the manifold or intake (post S/C, if possible)... if it starts and turns over a few times then you are missing fuel. If the starting fluid doesn't help you've likely got a problem with ignition (no spark).

Sometimes, even the engine turning over some will get it to fire up and draw fuel through the lines more easily.

Is the fuel pump getting 12v power? Was the fuel pump automatic shut off inertia switch (or emergency shutoff) somehow activated? Do you have fuel pressure? (There will be a little schreader tipe in valve somewhere on the fuel rail or fuel lines to stick a gauge.)

Do you smell rich gasoline fumes from the tailpipe or engine bay? If your turning it over and it's not firing... and your fuel delivery is functional then you'll smell the unburnt fuel from the exhaust pipe or elsewhere.

knownothingmags
04-26-2011, 01:01 PM
i have squirted fuel into the intake pre-SC and it started like a champ, then of course died out.

fuel pump dead?
i cant hear the pump runing at all.

Pneumagger
04-26-2011, 01:22 PM
Sounds like you have a fuel pressure or distribution issue.
You have a three things to check:

1) Was the emergency/inertia fuel shut off switch closed? It may need reset. Consult your manual to locate it.

2) Is the fuel pump getting power. Use a multimeter to check the voltage at the pump and at the fuse box.

3) Do you have adequete fuel pressure? There ahould be some sort of schraeder-type valve near or on the fuel rail or pressure regulator that you can check with a very cheap PSI gauge. Is your fuel pressure regulator working?

4) Are your injectors getting power? Check the fuses and check them to feel if they are firing.

You can check all of this with a cheap DMM and gauge at home. Just hope the issue is not random electrical problems or computer because you'll either be spending alot of money or ready to give up on life while looking for it. I had a car with random fuel pump wiring/relay problem once... so I hotwired the fuel pump for 12v power instead of finding the culprit.

Pneumagger
04-26-2011, 01:25 PM
Also, be careful squirting fuel atraight into the intake of a forced induction system (especially a fuel injected motor) because if there is a backfire it could damage the supercharger/blower/turbo.

C_losjoker
04-26-2011, 01:30 PM
Could be the new fuel filter is bad/ clogged, I have had that happen before. Try putting the old one back in, if it does start let it run for a while to be sure. Been a 06 I can't think it be a pump.

tolar250
04-26-2011, 01:47 PM
have you checked the fuse for the circuit that the fuel pump is on? it could have possibly blown out. i'd also check the fuel pump relay to make sure it didn't fry somehow when you plugged it back in.

knownothingmags
04-26-2011, 02:58 PM
put old filter back in.

even checked all the fuses and relays all seems to be fine.

maniacmechanic
04-26-2011, 04:47 PM
Fuel pump's ( nowdays ) are all electric , kick the fuel tank , it's worked for me before

Sounds like Pneumagger knows whats going on , listen to him

C_losjoker
04-26-2011, 05:17 PM
Yeah, he has some good advice. also if I remember correctly some cars have another fuel filter usually right before it goes into the main one. just a small one clear cylinder with a cork or basic fiber filter inside. They are there to take out bigger stuff before going into the main filter. might check see if you have one of those on there, if fuel is making it there and pass it.

knownothingmags
04-26-2011, 05:38 PM
tested the voltage at the fuse for the fuel pump nothing i think the fuel pump is dead.

i hit the fuel tank already.

knownothingmags
04-26-2011, 08:57 PM
i fixed the car mods you sure can CLOSE THIS THREAD.
thankyou.

C_losjoker
04-27-2011, 01:58 AM
ok what was the trouble, case we have the same down the line.