diagnose the problem with my car

I drive a 1995 Oldsmobile. It has a little over 100,000 mi. on it. Just recently, I have been having trouble starting it. When I put the key in the ignition and turn the key, the engine turns over just fine. No strange noises are made…

However, about one half second to a second after the car starts, it immediately shuts down. I can do this over and over with the same result. The car will start, run for second, shutdown. A friend of mine who knows cars well suggested that it may be my fuel filter. We decided to replace the fuel filter. Unfortunately, nothing changed. Obviously, it’s not the fuel filter.

I can’t keep it running so I am not able to drive. Tomorrow morning, I’m going to have it towed to the mechanic to look at.

Before I do, what do you think the problem is? The vacuum seems fine and I think it’s a problem with my fuel lines. Have you ever had this problem? What’s your best guess at what it might be?

A 95 Olds could very well have a microchip in the ignition key. On may cars if the chips is not recognized, the car will start and die, start and die. Lather rinse repeat.
This condition can be caused by either a key chip going bad (hey it happens) or the antenna ring around the key hole going bad.
You might check the fuses before you have it towed.

Yes, there is a microchip on the key… I always wondered what that protrusion was.

So, I’ve never really dealt with fuses… How do I know if it is the circuit? What do I look for that would indicate a blown fuse?

I can’t think of how a fuel line problem would cause the symptom described. If they can flow enough gas to start the engine, they can flow enough to idle.

Almost certainly it’s an electrical problem. It could be what Rick described, a faulty ignition switch (as in electrical switch, not lock cylinder), or a malfunctioning relay. I’m sure there are other possibilities, but none pop to mind.

The simple thing to do is test all the fuses. There might be more than one fuse block - check the owner’s manual to see. Turn the ignition to “on” and check them with a test light.

So, if it is the case of the key malfunctioning, then, what is the solution? A new key or a new fuse?

Should I replace one, or both? (if it is)

If the key is malfunctioning, the solution is a new key.

The suggestion to check the fuses is not related to the possibiliity of a faulty key. It’s just a simple thing to do which, although a long shot, might resolve the problem and save the time, money, and trouble of a tow and inspection by a shop. Replace a given fuse only if it’s blown.

3800 Series engine? Could be your key. Or it could be the Cam sensor, Crank sensor, or TPS sensor. Is the car throwing any codes (engine light)?

Nope… no lights.

yes, it is a 3800. I changed the spark plugs about two months ago… if that matters. the problem didn’t start til about a week ago, however.

if the key is malfunctioning, then the fix is a new key. If the antenna ring is the problem, then a new antenna ring is the solution. The antenna is connected to some control module (Body control module?) If that is the problem then …
My suggestion for checking the fuses was because what ever circuit the control for this anti-theft circuit is covered by a fuse. If that fuse is blown, then the chiped key won’t work.
The trick is knowing which part to change. It is worth the money to pay a pro to diagnose this condition.
As far as the suggestion about cam, crank and TPS sensors goes, I’m like Gary T here, I can’t see how that type of failure could result in a repeatable failure of the type described.

fair enough… all appreciated. How about this approach:
I attend school five hours away from homeand this car used to my grandfathers
I have an electric door opener fab on my key chain. It broke one lucky day and I found out that my father had duplicate.

is it worth the phone call to see if a duplicate key was made by the manufacturer? He could overnight that to me… however, if it’s not the key, will this new key damage anything or vice versa? if he had a second electric opener (or whatever they’re called) I can only imagine a duplicate key is right around the corner.

with the chances of it being the key, and the ability to receive a free key, should I give it a go

by the way: I have no idea what the antenna portion is

hijack: is there anyway to turn an IR port on a cell phone into an electronic door opener (for my car doors, not the garage door) I’ve seen it done before with remote controls and IR ports. are we comparing apples and oranges?

car question: priority

This might sound like it comes from left feild but hear me out. Oil pressure sender.
The car starts and runs and then shuts down. We have fuel, spark and compression. The fuel pump needs a signal from the engine that it has oil pressure to stay running. It is a fairly cheap fix if you replace it yourself.

Rick and Gary T will be back to straighten me out if I am way wrong.

The remote has nothing to do with the chip in the key. If you grandfather has a key attached to that remote, and that key is to the car you are driving, then have them overnight it. It probably / maybe will fix your problem. A non programmed key will not damage anything in the system, the car will not start.
Older GM cars had 12 different key chips, and keys could be ordered by chip number (Plus they had to be physically cut to the correct keyway). I do not know if that is still the case, or if they have gone to random codes programmed into the car via a diagnostic link. Asking at the dealer’s parts counter should answer this question.

Could you? Sure with enough time and money, we could probably make your cell phone start and drive the damn car. The questions are since you already have a remote that works, why would you want to? Also are you willing to spend the money it will take to do so? (Probably cost way more than a new remote will)
At least you didn’t ask if your grandfather held the remote to the cell phone would your car unlock… :smiley:

I just went through this on my car . . . an 1985 Chevy Celebrity

#1 - check the EGR valve (Exhaust Gas Recovery). If it’s not working, the car will start, but then shut down because the valve won’t open.

#2 - if you have fuel injection, one or more of the injectors may be bad, and sending a wrong signal to the ignition system.

It cost me parts and labor to replace the fuel pump, computer, fuel filter and a couple of other things before I brought it to a different mechanic who properly identifed the injector problem. All told, it cost me over $1200 for what should have been about $500 (and, most of that was parts - my EGR valve was almost $200 alone).



I’m still not sure of the problem. However, I’m taking the advice that seemed to be agreed upon in this thread…

Yesterday, my father sent two extra keys I had for my car via overnight mail. I’m going to check the circuits and new keys and with some this is the problem.

If that doesn’t work, then I’m just going to get it towed in and looked at professionally.

He may have sent the overnight mail after 3 in which case I may not get it today but I’ll keep you all updated.

UPDATE 2: keys came, a day late… no circuit problems, different key same problem. Tow truck in the morning. :frowning:

I wonder if they had the Nylon Cam timing gear in '94. GM are geniuses for that one.

Good luck. Hopefully they’ll find that its an inexpensive sensor failure.


this morning I had my car towed into the mechanic.

whoever said “anti-theft problem with the ignition” pat yourself on the back, you are correct.

whoever said replacing the entire ignition would cost $400 should punch yourself in the face… so you know what it felt like when i was told the cost of everything.
Thank god for a sympathic father who understands that his son is broke college student.

okay, ironically, one of my friends just called… she lent her car to her neighbor.

As a nice gesture, her neighbor put five dollars worth of gas in her car. The problem is: her car runs on diesel and…yep…you guessed it… her neighbor put unleaded in there. It’s a 14 gal. tank so a little over 2 gal. was put in there. it’s a bad day for cars.

of all the people, she calls me for advice. I just said to “have it towed… don’t even attempt to drive.”

How dangerous or bad is this for the engine if she (hypothetically) drove it.

About a whole buncha money bad, that’s how!

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Ack, preview is the best way to avoid those annoying BASIC posts… :smack: