2003 Malibu starts but stalls immediatly?


the_unicycle_guy
05-28-2009, 10:47 AM
Hey everyone,

The car turns over strong, and will fire every now and then. The car will start sometimes and dies within a few seconds, regardless of giving it gas. Sounds like the fuel pump is running when the key is turned on. Sounds like it's not getting gas or not letting it fire. Got it brought back on a flatbed after the problem first started a few days ago and it started up fine and ran fine. Turned it on and off a few times with no problems, but it started doing the same thing the next day, and hasn't ran since. Had a similar problem on another car and it turned out to be a cracked distributor letting moisture in. Sprayed the wires off with wire dry, but the car doesn't have a distributor cap like my other car did, so not sure if opening it and spraying it would help.

Any suggestions? Thanks a lot.

Airjer_
05-28-2009, 11:32 AM
Whats your fuel pressure at?

the_unicycle_guy
05-28-2009, 02:41 PM
No idea. Don't have a fuel pressure test kit. Could pick one up and check it out, though. I didn't think about checking it beforehand.

Thanks.

EDIT:

Fuel pressure is between 50 and 55 PSI. Book says the PSI should be 52 -59.

manicmechanix
05-28-2009, 06:06 PM
Are you getting spark at both of the first two plugs near the radiator side?

the_unicycle_guy
05-28-2009, 07:17 PM
The two plugs to the left on the front of the engine have good spark.

Car was running perfectly fine until this. It all started after driving about 10 miles, parking and turning it off for a minute or two, then wouldn't start again. Maybe that'll help spark some ideas.

manicmechanix
05-28-2009, 11:01 PM
unplug the 10 way connecter that goes to the injectors and on the side to the PCM check with a noid light for injector pulse while cranking or use a test light connected +Battery. You could also unhook the MAP sensor and see if it will start but I doubt it will. You could also unplug the TPS and try just in case the TPS is giving a clear flood output. Also check fuses to PCM/inj.

the_unicycle_guy
05-29-2009, 04:02 PM
Tried disconnecting both the TPS and MAP sensor individually and neither helped. The TPS seemed to allow the car to fire slightly more than it has been, but that could be both my imagination and the car doing it's own thing- needless to say it still wouldn't start. Also checked the PCM/INJ fuse and it's good. Gave a quick glance at all the fuses I could see in the panel and they seem to be fine. Didn't check them all, though. Code reader is giving no codes.

I'll go get a loaner Noid light and check that tonight or tomorrow. Thanks for all the help so far guys.

sbriar
05-30-2009, 10:54 PM
It could be your Oil Pressure Sensor, the fuel pump seems to be working because it primes up for start, after the car starts the oil pressure sensor takes over and keeps your pump running, if the main computer does not sense any oil pressure it will shut off the pump.
Also check your main connection from your fuel pump, it is the 7 or 8 pin connector located on the body next to the gas tank, unplug it and see if you see any spread apart connections on the female side of the plug.
I replaced 3 fuel pumps in my 03 Malibu before finding out that I had a bad plug. I removed the connector from the car by taking out the back seat, drilled out the connector so wires would run through the connector and hard wired it, after by-passing this connector I haven't had any fuel pump problems.

Airjer_
05-31-2009, 12:05 PM
It could be your Oil Pressure Sensor, the fuel pump seems to be working because it primes up for start, after the car starts the oil pressure sensor takes over and keeps your pump running, if the main computer does not sense any oil pressure it will shut off the pump.

Are you sure about that?

manicmechanix
05-31-2009, 02:12 PM
It could be your Oil Pressure Sensor, the fuel pump seems to be working because it primes up for start, after the car starts the oil pressure sensor takes over and keeps your pump running, if the main computer does not sense any oil pressure it will shut off the pump.

GM use to wire the fuel pump through the oil pressure switch but they stopped doing it that way some time in the mid-90's model years.


Also check your main connection from your fuel pump, it is the 7 or 8 pin connector located on the body next to the gas tank, unplug it and see if you see any spread apart connections on the female side of the plug.
I replaced 3 fuel pumps in my 03 Malibu before finding out that I had a bad plug. I removed the connector from the car by taking out the back seat, drilled out the connector so wires would run through the connector and hard wired it, after by-passing this connector I haven't had any fuel pump problems.

This could be a possibility if he had a fuel pressure problem, but he said he has good fuel pressure. He's also said he has spark from at least 2 coils. Based on what we know so far he needs to find out if his injectors are being pulsed and go from there.

I should correct something about using a noid light to test injector pulse at the 10-way connector. A regular noid light probably won't be able to bridge the two halves of the injector connection without an inline adapter harness. But the pin layout is A,B,C for injectors 1,2,3, and H,J,K for injectors 6,5,4. There should be +battery voltage with key ON supplied through the injector side of the harness at those pins, and appling +battery to the PCM side at those pins should flash the test light while cranking.

sbriar
05-31-2009, 03:49 PM
GM use to wire the fuel pump through the oil pressure switch but they stopped doing it that way some time in the mid-90's model years.

You are right, my mistake. I looked in the Hanyes Manual and it says "If the PCM senses there is NO signal from the camshaft or crankshaft sensors (as with the engine not running or cranking), the PCM will de-energize the relay."

brokemalibu
06-04-2009, 05:05 PM
I have the identical problem. Have Spark, Have fuel pressure, Loosing patience. If you fixed It please tell me what you did.

manicmechanix
06-04-2009, 07:05 PM
I have the identical problem. Have Spark, Have fuel pressure, Loosing patience. If you fixed It please tell me what you did.

Why don't you follow the diagnostic in this thread to see if your injectors are being pulsed? What's causing the other guys Malibu not to run isn't necessarily the same thing causing yours not to run.

brokemalibu
06-05-2009, 07:54 PM
Fixed the malibu. It was a paslock problem. added a resistor to the ignition. cost one buck. To diagnose the prob, just turn the ignition on for ten min the turn off and it started. If this works you have a paslock prob. A guy goes by handle, ponchanutty has the fix. Worked for me. was thrilled. others say they had just a good a result and it lasted. Good luck all Thanx Mike

sbriar
06-06-2009, 08:51 AM
Where exactly do you add this resistor?

manicmechanix
06-06-2009, 04:51 PM
Fixed the malibu. It was a paslock problem. added a resistor to the ignition. cost one buck. To diagnose the prob, just turn the ignition on for ten min the turn off and it started. If this works you have a paslock prob. A guy goes by handle, ponchanutty has the fix. Worked for me. was thrilled. others say they had just a good a result and it lasted. Good luck all Thanx Mike

Thanks for get back about your fix. I thought youalready knew about the Passlock and what the theft light indicated, so I assumed that wasn't what was shutting off your injectors. I also assume the other guys problem isn't Passlock, but I wonder why he's never gotten back about his car.

the_unicycle_guy
06-06-2009, 10:26 PM
Turned out to be the alarm. Wasn't my car so I had no idea that that could be the problem. My father-in-law took the car and was just as stumped as I was. Used to be his car and he eventually noticed the light flashing. Wish I would have figured that out sooner. He said that the alarm reset itself after being loaded onto the flatbed because it was raised up on an angle. Any idea why it's arming itself in the first place?

Where are you adding the resistor to prevent this problem?

Thanks for all the help guys.

manicmechanix
06-07-2009, 03:31 AM
Mystery solved. It was the Passlock and not a real hard fault shitting your cars injectors down :icon16:.

Regarding bypassing the Passlock with a resistor, there's a big thread on here cov ering that topic. Personally, I wouldn't bypass it. If the theftlock kept setting, I'd replace the ignition cylinder. I think the resistor can be replaced in the wire just before it connect to the BCM. It might be easier to do it there.

sbriar
06-07-2009, 09:18 AM
what resistor value or size would you use

clutch492
07-24-2009, 04:50 AM
There are 2 small wires that follow the steering column down. First you need to check the resistor size that is on your key, and find an in-line resistor at radio shack that is very nearly identical in resistance. Cut the 2 wires on the column and solder in the resistor on the car side of the wires (not to the wires that go up to the key). The computer needs to see this resistance to know that the proper key is in the tumbler.

Go to this site and you will get a very good idea of what to do.

http://newrockies.ca/vatsbypass/

CalifOkie
07-25-2009, 12:27 AM
That does work but the downside of it is that the passlock system was designed to make it very difficult for a thief to steal your car. Simply popping out the lock cylinder and starting it with a screwdriver no longer worked... However, after you do that modification your car can be stole with a screwdriver.

CalifOkie
07-25-2009, 12:48 AM
Another thing to try before slicing into those wires is a second key. Many times in a passlock problem the sensor in the lock cylinder isn't what fails. The key itself can fail causing the same problem. So I would suggest if your security light is on and you can't get it to stay running. Try your wife's key in it first before disabling the passlock system. If it starts then all you have to is drive down to the dealership and get yourself a new key made.

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