Mystery breakdown

Maintenance/Repairs
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1

My manual 2004 Hyundai Elantra with 92,000 has been killing me lately. It has stopped running 3 different times but it will restart afterwards. Never triggers a check engine light. No other obvious signs like engine temp gage too high/low, or illuminated lights on the dash. These are the three times it has acted up.

1, about 10 days ago after driving to school (4 miles from my house) Its idling before I shut it off, and it has a rough idle, I watch the RPMs dip, and instead of rebounding (occasionally there is a rough idle) the car stalls. Won’t restart immediately, but it will turn over fine. I come back to my car a couple hours later and it restarts fine, I drive it home, no problem.

  1. Last saturday I drive from las vegas to phoenix, the car runs like a champ. The next day I take my uncle to the airport at midnight, I stop to get gas on the way home, I pull out of the gas station and am slowing down (idleing) as I approach a light, and the engine shuts off before I come to a stop (I first noticed the power steering was gone). All the dashboard lights come on. It turns over but won’t start, and a good samaritan helps me push it back to the gas station. I immediately try to restart it but no dice. The next day I have it towed to a shop, it starts up for the mechanic fine, he even drives it around no problem. He tells me it doesn’t trigger a code, and even after checking forums with similar symptoms he tells me his best bet is a fuel pump problem but he’s not sure.

  2. Today I drive it back form phoenix to vegas, not stopping for anything because I’m too scared to bring the RPMs down for any reason because that’s the only link I can see between the engine shutting off. I’m finally a quarter mile from my place at a stop light and I can feel the engine getting bogged down so I rev the engine while I wait for the light to turn green. I make it to my place and as I reverse into my parking spot with the engine about idleing, it dies and I coast into my spot. I then thank The Almighty for helping me make it back. But i immediately try to restart it and it starts fine.

So I took it to a mechanic right away and he says he thinks its a dirty throttle box, or a dirty something box. He says that he guesses that based on the rough idle that it has sometimes that will cause the RPMs to dip and rebound. So I’m going back tomorrow and he’s going to look into this throttle box to see if it’s dirty; if it is dirty then he’s going to clean that and hope it solves the problem.

I have no idea what the issue is. Any takers?

2

It’s called a throttle body.
I recommend you get that and the idle air control valve (IACV) cleaned too.
After 11 years and nearly 100K miles they are the prime suspects.

3

My former mechanic (now retired) omnce told me that if a car dosen’t start, it could only be one of two things: no fuel or no spark. I keep an old-fashioned ignition timing light for diagnostic purposes. Once I had a no-start problem and, while cranking the engine, I used the timing light to determine there was electricity in each of the spark plug wires. That narrowed the problem to a fuel issue.