Car wont start after driving it and turning it off .. have to wait up to 2 hours

i have a very frustrating problem i need some help with.

car:
2002 Oldsmobile Alero GLS
3.4 liter
6 cylinder
170k

if i drive anywhere and turn off the car, it will not start again for up to 2 hours… which makes it very difficult to get around… i have to leave the car on for short stops always risking it being stolen… everything is a major hassel like getting groceries and not letting the food go bad in the heat. I replaced the ignition switch… that seemed to fix it at first… and it did make the cranking/turn over better… but same problem… last night i replaced the fuel filter… thinking that was clogged and creating pressure and maybe it wasn’t starting til the pressure went down. . idk

i have scoured the net repeatedly and haven’t really gotten anywhere. the ignition cylinder comes out of the ignition switch since i changed it… which is annoying… not sure how to get it to stay in there… it cranks and turns over no problem… battery and alternator fine… my father who did his time at GM replaced all the engine wiring from LKQ salvage… because when i got it from copart there had been a blowout that popped the serpentine belt of vice versa and that belt flew around and ripped out the wiring… the car drives fine… doesn’t sound super great when idling… only codes i’m getting is for the catalytic converter… test the o2 sensors … they’re fine… i think it might have something to do with the wiring maybe… somewhere online i read that maybe the wiring was getting to hot… no idea what that even means… i have heard the fuel pump whirring up before… and it does drive if it’s been sitting awhile… i have a new cheapo 30 dollar fuel pump from online in the trunk i haven’t put in… i dont think thats the problem but what do i know… i need some help diagnosing the issue

Try driving it around, back home, shut off, then restart with gas pedal to the floor.

can you test fuel pressure when it won’t start? This sounds just like many Chevy’s that I have had when the fuel pumps went out.

I suppose I’ll have to get something to test the fuel pressure… I just put in a full tank of gas so… I hope it’s not that…

I have tried it with the pedal to the floor… And halfway… And no pedal… No change

Drive the vehicle until you know it won’t restart and stop at home.

Open the hood, and remove one of the spark plug wires from a plug, and plug an extra spark plug into the wire.

Lay the spark plug on a metal part of the engine to ground it.

Now have someone crank the engine over while watching the tip of the spark plug.

Is there a bright blue spark at the tip of the spark plug?

Or is the spark more of a yellow color or nonexistent?

If it’s the latter, the problem might be with the ignition module being heat soaked.

https://www.rockauto.com/en/catalog/oldsmobile,2002,alero,3.4l+v6,1382194,ignition,ignition+control+module+(icm),7172

Tester

1 Like

i will have to get a fuel pressure test gauge… does anyone know where to plug it in under the hood on this vehicle? i can check fuses but i don’t know how to check the voltage and ground like on scotty kilmers channel for this… i have a voltimeter with an electronic display… but i don’t know where to set the dial or where to attach it to the vehicle…

and anyone think it might be something else?

Or the ignition coil being heat soaked

There’s three ignition coils.

Are you saying all three ignition coils are being effected by heat at the same time?

I’ve never seen that one!

Tester

The ignition module is by far the most common cause of that problem on GMs with coil pack wasted spark ignition…

alright… i’ve made some progress now i really need some quick help. i just changed the ignition control module, all 3 ignition coils, and the plug wires while it was hot and wouldn’t start… it fixed the problem! it starts when it wouldn’t before! however… now it runs super rough then dies… i rechecked and triple check to make sure the wires were all going to the right place and that everything was securely seated/tightened… all i know to think may be the cause is that maybe i moved one of the old spark plugs off its mark? one particular spark plug wire end was difficult … it was just under the alternator on the passenger side. anyone know what i need to do? i used dielectric grease to grease the icm top and bottom and the spark plug ends that the wires plug into

the wire diagram i had followed was wrong. i have them right now. i thought it had fixed the problem. it didn’t. so does this mean it must be the fuel pump?

Where I’d start with this problem is to follow Tester’s advice above and make sure you have a good visual spark on all the spark plugs during cranking. You have to do this test when it cranks but won’t start. If you’ve verified there’s a spark problem, you could then try using a heat gun or freeze spray on the ignition module, coils, crank position sensor to try to identify which heat related part is failing. If the visual spark test proves spark isn’t the problem, then your fuel pressure test idea would be a good place to try next.

B/c the ignition switch seemed to have an effect, good idea to measure the voltage at the battery terminals when the engine is idling. It should be in the 13.5 to 15.5 volt-DC range. If so, measure the amount of AC ripple coming from the alternator by changing the meter from DC mode to AC mode. There’s probably close to a mile of wiring in your car, and with the harness being changed out, you may have some major sleuthing in head of you until you find all the problems. Rely as much as you can on the computer diagnostic codes for clues. Measuring the wet/dry cylinder compressions is often a good idea with weird problems like this too. If it runs better at higher rpms and engine loads than at idle, unlikely to be the cat causing these symptoms. An air leak in the exhaust system could though. Are you able to measure the fuel trims?

Dielectric grease? Remember that’s an insulator, intended to prevent high voltage arcing, and the grease part can prevent water intrusion. Applying it to stuff that is supposed to be connected together and make a good electrical connection can be problematic sometimes, b/c of its insulator properties.

Hi, I’ve been trying to fix my car and have run into a lot of trouble and would really appreciate any help.

Oldsmobile Alero GLS 2002

This is a list of things I have already done (in order):

car wasn’t cranking or starting:
replaced ignition control switch
this worked until it didn’t, wouldn’t start
replaced fuel filter - no effect
replaced ignition control module and the 3 ignition coils
this worked until it wouldn’t start again.

at this point, I had to have it towed to a shop who tested fuel pressure and checked everything they could til they realized the ignition cylinder which was loose and would come out of the ignition switch was causing the computer to lock up or something… so the guy said he superglued it lol… anyway it did work for awhile after that. he also said that the ignition control module fuse was blowing.

for awhile when it wouldn’t start i could just check the ignition control module fuse and replace it when it was burned. that worked for awhile but the cranking/starting seemed to grow weak not long before the end. i drove it home one day and it has not started since.

i have a code reader (which i have all the reports for and can show them to you)… and it suggested several issues … and a common fix among them being the body control module.

So I ordered a body control module. I saw on youtube a mechanic showing that if you place the ignition in the ‘on’ position that you can then remove the bcm and replace it and it will reprogram itself.

Well, it either didn’t work or that wasn’t the issue. I had also tried resetting the computer before this by detaching the negative cable on the battery. That had no effect. I also checked all fuses… I have even swapped out the big box fuses … the fuses seem fine. It cranks very strong but will not start. I replaced the front 3 spark plugs… the back 3, I don’t think I can get to. I tried to do a spark test but the metal thing inside the end of the wire came out when i detached it from the plug. I think i was able to get it back on securely … but anyway I could not see a spark. so I don’t know if the wire is messed up and i didn’t perform a good test.

Reading reviews on this car… most people never get it fixed… they fix one thing and then it’s another. Other people say it’s a great car. I really need to fix it to work to get the money to get another car.

I hate to spend the 400+ bucks it would take to have it towed to a dealership to reprogram/flash the bcm just to even see if that is the issue when it may not even be the issue. What can I do? I don’t understand how to test the battery terminals (i do have a voltimeter, but I don’t know how to use it)… also the car won’t idle to test it because it wont start. I don’t understand most of what George said.

The nice thing about forums on the web is that we can post our thoughts even if we are wrong. You seem to be spinning your wheels on a discontinued 12 year old vehicle with lots of miles and lots of problems. Frankly I would not spend anymore money on it and just replace it. There are places that will come and tow it off. I would think that even if you do fix it now it will just keep having problems.