Alero Not Starting - But not the usual

[Scarlett_77]

My alero will turn over but not start. My security light is not on. I had the battery replaced and it started immediately. I drove around all day and night without any problems. After parking the car overnight (8hrs) it wouldn't start in the am. Same thing turn over but no start. All lights and chimes are on so there doesnt seem to be a power loss. Any ideas? Thanks

[xeroinfinity]

Welcome to AF !

I would double check those battery connections first.
It could be several things causing this.

Could be fuel filter clogged, or bad fuel pump.
Can you hear the fuel pump run when you turn the key on?

Faulty coils, faulty emission sytem, wet or damaged ignition componets.
Improperly gapped spark plugs, your crankshaft position sensor.

When it was running, was their any service lights on in the dash ?

[Scarlett_77]

Originally Posted by xeroinfinity

Welcome to AF !

I would double check those battery connections first.
It could be several things causing this.

Could be fuel filter clogged, or bad fuel pump.
Can you hear the fuel pump run when you turn the key on?

Faulty coils, faulty emission sytem, wet or damaged ignition componets.
Improperly gapped spark plugs, your crankshaft position sensor.

When it was running, was their any service lights on in the dash ?

There were no lights on at all when it was running. It was perfectly normal with great power (no bogging or cutting out). I was told it may be the "key reader" and perhaps installing a simple "bypass" may fix the problem? I am really not knowledgeable at all!! I do know that the car worked fine for the entire day and we attempted to start again with a new battery but nothing this time. Fuel is fine, spark is fine and no error codes are being given. I have tried both original keys I have but nothing. Any help would be great. My understanding is that everything else seems to be fine. Thanks again.

[xeroinfinity]

An important note, what size is your motor ??

You could try the passlock relearn.
I wouldnt suggest "by passing" anything

Attempt to start the car, leaving the key in the "ON" position for 10 min.
Turn the key to off for 1 min.
Then repeat this 3 times.

If that was the problem then it should start.
Good Luck

[Scarlett_77]

Originally Posted by xeroinfinity

An important note, what size is your motor ??

You could try the passlock relearn.
I wouldnt suggest "by passing" anything

Attempt to start the car, leaving the key in the "ON" position for 10 min.
Turn the key to off for 1 min.
Then repeat this 3 times.

If that was the problem then it should start.
Good Luck

Well..we have tried everything. They installled a new key tumbler..this activated the security. A key relearn was done successfully (security light was flashing and stopped after 10 mins) but still no start. The car will run when the engine is primed. If you leave it run for a bit and turn it off...it will start again. After sitting for an hour or two it will not start again. Once the car is running (after being primed) the fuel injectors will work properly and the car runs great. but for some reason the car will not start on its own unless it has been warmed up. The temp sensors were checked and replaced with no luck. No codes whatsoever are being stored. Could it be a glitch in the BCM? Any input would be great. The motor is (2002) v6 3.4L 180,000 kms...no other problems. Thanks

[xeroinfinity]

With those miles I'd suggest the fuel filter still(if you hadnt already).
If that doesnt work get the fuel pressure tested.

The shrader valve is on the pass side of the motor(should be capped),
between the power steering pump and the alternator.
Should be between 41-47psi , if not either your fuel pressure regulators bad.

You can by or rent a tool to test your fuel pressure from most parts stores.

this pic has the location of that vavle on the end of the fuel rail.
3.4 engine
Well you cant see the vavle,
its behind the engine lift brace(with the Oval hole in it).

[BNaylor]

I get alot higher than that JC. A fuel pump working well on a '02 Alero with 3400 SFI will kick butt! Reading at fuel pump prime and at idle is way up is the 50 psi range and up towards 60 psi. See pic below:


'02 Alero GL2 3400 SFI fuel pressure reading at idle

[xeroinfinity]

My bad !

I didnt check the year.
I see Scarlett_77 has a 2002 Oldsmobile Alero.

That would be higher, around 50psi at idle.

Nice pic, and gauge !

[Scarlett_77]

Well...I had my personal mechanic and the dealer involved. They concluded the 'computer' needed to be replaced. They did this with a complete programming and the car was fine. Worked great. The car was starting and sounding better than ever. However, after sitting for 3 hours in the cold..guess what..no start... If I was to disconnect the battery overnight and reconnect on the am..the car will start fine. I am extrememly frustrated. Any thoughts? Thanks.

Originally Posted by xeroinfinity

My bad !

I didnt check the year.
I see Scarlett_77 has a 2002 Oldsmobile Alero.

That would be higher, around 50psi at idle.

Nice pic, and gauge !