Hyundai Eleantra - Exhaust leak and no power?

[Dabba]

Hey guys. I feel like this kind of a dumb question but I need to ask.

My friend doesnt know a lot about cars.. actually, nearly nothing. He tells me his car was making weird noises so he didnt want to take it out. Its a 2000 by the way, with many miles on the clock. Anyway, I go over there with an error code reader, plug it in and start it up. Right away I hear a massive exhaust leak. Like, the pipe is completely busted somewhere right behind the front tires and exhaust is pooring out. Besides that, no weird noises at all. The code reader even tells us what we already know and just mentions the exahust leak, nothing else. I figure no big deal, say you can still dive it, just bring it to a shop to get fixed.

He tries to drive it today and tells me it stuggles to make 20mph. I don't know if something else is going that we missed, or is it possible that the engine doesnt like the loss of backpressure from the exhaust leak? I know a lot of older engines we're used to gain HP from chopping off exhaust elements, but I also know some engines really don't like it. Do you think it's that or the computer is doing something because of the exhaust leak? I don't want him throwing money at a dead car.

Thanks guys

 

[Blue85]

I thought the only way for a Hyundai to *lose* power would be to start absorbing it, or spinning backwards. (Go ahead people and tell me how wrong I am and Hyundai's are great or something...blah, blah, who cares, the point is that it's funny.)

An engine could make a little less torque from lack of backpressure (not really worth debating here...) but it won't be so major you can't drive it. It's possible the fuel trims are way off from fresh air hitting the O2 sensor, but that should also be mostly driveable (probably a rough idle, though). It's also possible the ECM is limping thinking there is danger to fry the cat, so you might grab the codes again. If you really think the car is "dead", do a compression test or leakdown test. Otherwise, just get the exhaust fixed so you can at least hear what's going on with it - maybe even cobble it temporarily to do more troubleshooting.

 

[dyeager535]

I lost the flex pipe behind the converter (converter and exhaust manifold are one piece in my '04 Accent, 1.4L) and I lost some MPG, but it drove normally. Never got the flashing "stop driving now!" MIL like I had with a misfire from bad plugs or bad gas.

Since the flex pipe is after the manifold/converter, it was only affecting the post-cat O2 sensor. If that car has the integral converter, the O2 is mounted way up near the block, not sure how you'd get any sort of contaminated O2 reading up there. Besides, under power, it's not using it to trim fuel anyway. Different topic, but there may be something else going on.

Perhaps the exhaust is now plugged somehow?

 

[Dabba]

Damn. I figured it couldnt cause that much trouble but I was being hopeful. He said his mechanic told him the transmission would be going soon (Im not sure how he knew) but it sounds like a power problem. Its probably unrelated to the exhaust leak and coincidental. I'm going to go over there and test drive it and plug in the reader and see if it's anything easy to deal with. If not I'm pretty sure they're ready to junk it.

 

[dyeager535]

Yeah, doubt there is a whole lot of residual value in a 2000 Elantra lol.

I figure if I could sell my accent running with no issues, I'd still be very lucky to get $2000. But for $9000 back in '04, 140,000 miles so far, and still getting 40MPG, *I* can't complain about the thing. Might as well drive it until the wheels fall off.

 

[Fordum]

Real off the wall guess.
Something has plugged the exhaust, and the backpressure is escaping wherever it can,but not enough can get out the loose connection for the engine to run properly.

Probably the cat has come apart and a piece has plugged the exhaust.

 

[Dabba]

Yeah, doubt there is a whole lot of residual value in a 2000 Elantra lol.

I figure if I could sell my accent running with no issues, I'd still be very lucky to get $2000. But for $9000 back in '04, 140,000 miles so far, and still getting 40MPG, *I* can't complain about the thing. Might as well drive it until the wheels fall off.

Same way I feel about my 03 civic. Gonna drive it til it dies. Thought I'm tempted to throw a new motor in it before buying another beater. May be cheaper

Real off the wall guess.
Something has plugged the exhaust, and the backpressure is escaping wherever it can,but not enough can get out the loose connection for the engine to run properly.

Probably the cat has come apart and a piece has plugged the exhaust.

It would be really weird for the exhaust to break and also get blocked at the same time no? I guess i'll see the state it's in tomorrow.

 

[Fordum]

No, one would cause the other.
The exhaust would stop up, the resulting back pressure would find a way out through a joint not designed to handle that pressure thus causing the leak you are hearing.

 

[Dabba]

No, one would cause the other.
The exhaust would stop up, the resulting back pressure would find a way out through a joint not designed to handle that pressure thus causing the leak you are hearing.

True. There was just so much pouring out I can't see it haha

 

[SurfinCR]

this thread just brought back bad memories. the happiest day was the day the guy that bought my 2000 elantra drove home with it. the transmission went on mine at 97k they replaced it under warranty then went at 110k and they said to bad its out of warranty.

one thing to check is the exhaust manifold they were known for breaking.

stupid thing but has anyone checked the intake box? i've known of folks having a similar issue since their intake was stuffed up with acorns.

for what its worth the 2000 elantra engines are the same ones in dodge neons of the same year.