Author Topic: Engine Rattle plus Fire!!! (Read 4332 times)

funez · « **on:** December 21, 2008, 03:04:01 AM »

Hey guys, I'm new here. Ran into a serious problem with my 318i.

Well I went into work yesterday despite the snow storm. When I was going to leave, I had snow up to the door trim. After some shoveling, I had about 4 guys help me push the car out. We were at it for about 15 mins, my car started to heat up, but never came close to the red temp gauge.

It stalled a couple times... then I could smell something burning, one of my co-workers looked under the car and there was a small flame. It wasn't near the engine. It was under the car by the front passenger side. I'm guessing it was the catalytic converter. Wasn't very big but it was burning for awhile cause it was hard to get at with the snow in the way. A fire extinguisher did the job. I had the car towed home.

Once home, I turned it on. The car starts and runs. However, when I give it throttle there is a loud rattle sound, does it in neutral and in gear. I had a rattling sound before for the last couple weeks whenever I gave it throttle at around 3k. I was going to replace the chain tensioner because I thought thats what it was. However, this rattle is A LOT louder now. Also, I have a black soot like substance coming out of my exhaust when I give it hard throttle. I should also mention the heat in the car was getting very hot, much hotter than usual, forcing me to shut it off during the process.

I uploaded a video. Its painful to hear.. you can hear it the best towards the end of the video. The second video is with the hood open. sounds like its coming from inside the engine. My best guess is that the tensioner broke, chain guides broke apart or something, and i got pieces rattling in my engine. However, I'm not sure how this explains the fire.

In either case, it sounds bad, and I dont know if its worth fixing. The car is starting to rust, and although I only bought it about a year and a half ago, maybe I should just cut my loses.

http://www.youtube.com/watch?v=C2CUro8XhJM

http://www.youtube.com/watch?v=_u9_rpG_CZw

roundel318 · « **Reply #1 on:** December 21, 2008, 03:48:06 AM »

I checked both video's and I would recommend not running the motor until you get into the timing chain dept and see what's going on there, could be lots of things. Also could be sound of some other failed engine component, however I have no actual firsthand experience with those sorts of sounds in the M42 besides a worn timing chain tensioner and hydro valve tapppets.
In terms of the fire......
While the snow buildup theory is a bit remote, could a ton of snow buildup caused an electrical short of some sort (the primary 12v lead from the battery is up there)??
Of course since the exhaust is on the side too, that could be a factor.
Let's also not forget that snow is a pretty decent insulator of heat, could it have been a factor in preventing heat from escaping or something?
Just tossing some ideas out......
Where back east are you?

ak96ss · « **Reply #2 on:** December 21, 2008, 06:03:29 AM »

In the first video, it sounds to me like you blew the catalytic converter - the honeycomb is rattling around. If it was clogged, it would build a significant amount of heat. Perhaps that is what caused the fire and could very well be what is causing the soot.

Second video, though, definitely sounds like something is rattling inside - you need to at least pull the valve/cam cover and take a look. Hopefully you won't need to start digging in the timing chain area, but you should prepare yourself for the eventuality...

I wouldn't run the engine until I did that.

funez · « **Reply #3 on:** December 21, 2008, 10:07:24 AM »

Thanks for the replies

So the fire and the rattle could be completely unrelated...

Although I've been able to do all the work myself thus far, I think I'm gonna have to take it in to a shop for this one. Whatever it is, it doesnt sound good. I need my car running asap, so I dont think I have much of an option.

A couple suggestions I've had is that its a rod or my timing chain/rails have broken apart. Would the car still run in these situations?

ak96ss · « **Reply #4 on:** December 21, 2008, 11:12:22 AM »

Not if it was a rod loose, nor a broken chain. It could be little pieces of the rails loose in there, but given the fact that other than the horrible rattle it seemed to rev up OK, I don't think it's big enough pieces to affect the path of the chain dramatically.

I doubt that they are unrelated; stuff like that rarely happens simultaneously and independently, but I couldn't tell you how they could be related...

peerless · « **Reply #5 on:** December 21, 2008, 06:22:05 PM »

Dude, you take it to a shop and your going to have a repair bill so high you will cry and you can kiss Christmas good bye.

Cut your loss's and ditch the car, that engine is history.

You need to rebuild the engine and replace the cat. Your looking at several thousands of dollars. And if you have someone rebuild the engine that doesn't know what they are doing, you have just wasted a large amount of money.

You can buy another used car for the money its going to cost to rebuild the engine. Are you sure you have the finances for that?

Keep running your M42 and revving it up. Just let it go, its history.

B318M42W · « **Reply #6 on:** December 21, 2008, 06:51:52 PM »

just thinking out loud here...
it doesn't seem to be chain tensioner related, no diesel sound? but it IS RPM related... so maybe the waterpump? or maybe the idler gear(if your M42 has one)?? or maybe it's just simply knocking for some odd reason? might explain the excess amount of soute? what gas grade do you put in? any codes?? does the oil contain metal shavings???
throwing ideas...

funez · « **Reply #7 on:** December 21, 2008, 08:24:26 PM »

The weather is crappy and I got it outside right now. I'm gonna try to get an oil sample soon. I have no error codes, or anything suggesting anything is even wrong with the car besides the fact that it rattles like crazy. The black soot seems to have stopped coming out.

Peerless, while I do agree that the it sounds like the engine is toast, a rebuilt engine will cost the same as a crappy used car. If I had the funds to purchase a decent car, I would do so. I'd hate to put so much money into a car that isnt worth much, but I dont think I have much of a choice.

Besides, I dont know for sure exactly what the problem is.

The question is, what would cause a fire in what seemed to be my cat, and leave a terrible rattle in my engine. My friend is gonna bring his stethoscope by to try to isolate the sound's location. He recommended I do that first before taking parts of my engine apart.

JP 91iS · « **Reply #8 on:** December 22, 2008, 12:26:06 PM »

When you were stuck in the snow where you flooring it over and over in an effort to free yourself? You said it took 15 minutes to get out of the snow.

funez · « **Reply #9 on:** December 22, 2008, 11:29:36 PM »

Well I wasnt flooring it. I would give it gas, and release, give it gas, and release, to rock the car. If I got some movement I'd hold the gas, but I wouldnt say I was flooring it. I never redlined it, I might have hit the start of the red for a split second maybe once or twice, but it was usually around 4000 rpm at most.

Cobra Jet · « **Reply #10 on:** December 30, 2008, 09:21:31 AM »

Pull the exhaust pipe off after the header and shake the pipe, if you have a rattle, your catalytic converter is DONE, it fell apart within the shell. You can either remove ALL of the honeycomb and reinstall the pipe w/ a non-functional cat (the exhaust will be louder, the removal of or tampering w/ the emissions or cat system is illegal in some states if you get caught - and it will not pass the emissions test once inspected) - or you can go to a good muffler shop and have them remove the bad cat and install a hi-flow cat.

It's possible the cat was already deteriorating and by you "flooring it" to get unstuck, there was enough internal vibrations within the pipe that the cat just broke apart inside the pipe, clogging up the path for the exhaust to escape... Also, if your vehicle is not running 100% efficient, it's also possible that the fuel was not burning properly, thus the spent exhaust w/ fuel had heated up beyond normal and the cat caught fire... This would also explain any black "soot" you are experiencing from the exhaust (prior to your current problem and fire). This can happen, as the cat will get red hot, hot enough to melt the catalytic converter honeycomb within the exhaust pipe and hot enough to start a fire. Once the cat is damaged either by becoming clogged, broken up or even melted, you need to either remove it or replace it before more damages are caused.

You need to remove that exhaust FIRST, before driving the car or continually starting it to make sure the exhaust path is 100% clear & free of any debris...

After doing the above, THEN I would start checking for major internal engine failure.

funez · « **Reply #11 on:** January 06, 2009, 08:51:34 PM »

Thanks for the reply. Based on the sound from the videos, do you think its possible that its not the engine?

So 2 weeks after dropping my car off at the shop, I called today cause I hadn't heard anything. Basically he told me my engine is knocking (obviously) and that I probably have bent rods and need a new engine. He also said my clutch didn't feel right, and that he didnt even know where to begin with the whole fire thing. So the guy just basically didnt wanna deal with it and told me to get rid of the car. I asked him how much for a new engine with install and he said about 2500.

So I dunno if I should just get a second opinion or just go out into the market for a new car. I can get a 328 engine for about $500, but labour would probably break the deal on that. Plus I have to agree that I was getting some odd vibrations from the clutch, so the engine probably isnt the only problem.

Im thinking my best move is to buy a new car, and sell my 318i for parts. I just dont wanna write off the car so fast without knowing for sure whats going on with it. Am I just having wishful thinking, or is my car toast?