2003 Buick Century - 3.1L Dies, No Codes

[mikemiles]

I'm starting to pull out what hair I have left.

We have a long time customer with a 2003 Buick Century 3.1l with 100 k on the clock. The engine dies sometimes, we replaced the crankshaft sensor at the front cover in July and the engine was fine for a month and then we replaced the crankshaft sensor on the block in September and the engine did not die for a month. Customer came by today and it has died a dozen time from yesterday to this afternoon. No codes, it dies when coming to a stop and while driving at cruising speed.

Any ideas?

Mike Miles
Miles Automotive
Keller, TX.

[steven kiser]

while it's running tap the mass air flow meter and see if it stumbles. these can go bad and throw no codes. watch meter reading through scanner as well. fuel pumps can cause similar issues but once it starts it goes down hill quickly. another thing i've learned is that everything you've repaired in the past could have actually been real fail issues. another thing i would do is wiggle the wiring harness that attaches to the sensors. replacing them may have moved the harness enough to make contact and after a while it settled back into it fail position. the wire interruption may or may not throw codes. good luck, nothing gets the blood flowing like a good intermittent problem on a g.m. man i feel your pain. i've had some real head bangers.

[mikemiles]

Thanks Steven for taking time and the good advice. I'll try those suggestions Monday when the problem child arrives. Identifix's posts were mainly the security circuit, but customer has not the light flashing, but I was going to check that area. I will try your ideas first. This long time customer is "good people" they want to fix this problem before they trade it off, imagine that!
Mike Miles

[Tim Martin]

I'd be getting my lab scope out and checking the signal on various sensor inputs to the computer. I also would connect a fuel pressure gauge to the service port. It takes time but I usually can find the problem that way.

[steven kiser]

on a side note i have a module that clips onto the data link that reads and records the data stream. on more than a few occasions we've been able to down load the recorded information and seen the glitch. btw, the security light doesn't always flicker. i would re-burn first. this may not be a viable option for some shops but i have the tech 2. i found that even though oem scanners are very expensive they are becoming more and more necessary. the snap on verus has the ability to program. it's limited now but i'm hearing that it will be expanded on. hope it's true.

[92zman]

I have had a lot of mass air flow sensors do this but test out ok. I have just unhooked them and then drove the car and see how it does then.

[mikemiles]

Thanks everyone, the customer has not brought the car back for us to check over. Hopefully I will post a fix soon.
Mike Miles

[wbuxton]

Give me a call, since all we do is transmission work, I'm thinking you might have a bad lock up solenoid. Does it feel like not releasing the clutch on a standard when stopping? Or it dies before the stop?

[mikemiles]

Well folks, the customer traded the car off for a new Explorer. I thank you for your advice, I'm sure I will use it in the future.
Mike Miles

[steven kiser]

i love success stories like this. nothing feels better than a trouble job getting traded in or getting stolen. on occasion i've thought of stealing and burning a vehicle that's driving me nuts.