Loud Backfire. Won't start anymore.

[WarSaw]

I was driving through a parking lot going about 15mph not accelerating. I hear a very loud backfire, followed by 2 slightly quieter ones and then the car shut off. I stopped the car and tried to start it again. It started when I gave it gas but was popping and rpms were all over the place, so I quickly turned it off. When the tow truck arrived, the driver insisted i try to start the car again. I heard the loudest backfire in my life but it just kept cranking. After towing the car to my house and when it was twenty degrees warmer I tried starting it again. It would crank slowly but never turn over. A friend outside the car said the motor sounded like a whole bunch of stuff was rattling around inside. And thats how it sits now. Any help would be appreciated.

 

[ROOKIE1]

I would pull the upper timing cover to see if I still have a belt . Did it overheat or anything else . Recent work done to it . Pull plugs and crank by hand , does it turn easily ?

 

[xveganxcowboyx]

Yeah, check your timing belt. Sounds like you might have skipped a tooth, then snapped it or skipped some more.

 

[WarSaw]

The belt is still on, but I'm not sure if it skipped any teeth or not. No recent work has been done. There have been problems with multiple fuses shorting out though, not sure if its related or not.

 

[GMANS89GT]

bring the crank to tdc , check the timing marks on the crank and cams . if its rattling you my be in for head work . sound like the belt jumped time.

 

[zatomz]

If It's not any of the above check and see if you blew a head gasket, do a compression test after you check your timing marks.

 

[WarSaw]

Ok, sorry it took so long to get around to this. Other things came up, but now I finally have a good portion of time to devote to the car again.

The timing checks out, all three marks are still aligned and the crank turns fairly easy, with just one slightly hesitant spot in the rotation. But that is supposed to happen correct?

Could this problem be electrical? Maybe two months before this happened, the car randomly started to fuel cut at exactly 4000 rpm and die without constantly having the accelerator slightly depressed. This is with an fcd installed and running correctly for several months prior. When I disconnected the fcd and drove the car it ran perfect. I know that shouldn't work. Could this be related?

 

[WarSaw]

When checking spark plugs again, I found the plug in my fourth cylinder was smashed completely shut, as in a gap of 0. I set the gap back to what it was supposed to be, turned the crank by hand just to see if there was any resistance and then tried cranking the car again. The car started to turn over but it never quite made it. There was a knocking noise coming from the motor during cranking.

 

[turboglenn]

Ouch, time to pull her out and take her apart. I was going to hopefully suggest that it might be the CAS (the reason i say hopefuly is that i hoped you would get away with something minor as the fix, but now it sounds terminal)

You may have broken a rod or snapped a piston at the wrist pin. If something hit the plug and closed it up that means there's something extra in the cylinder (valve head, bolt etc..) or the piston is moving further up than it should.. (broken rod, piston etc..)

 

[blcktsiawd1987]

Take the head off and see if you can see anything in your cylinders or on your pistons that could be the culprit. With the head off you should be able to pinpoint the problem fairly easy.

 

[WarSaw]

If I found something in there, it would require a complete rebuild right?

 

[WarSaw]

I don't really have the time or experience to rebuild the motor if that is what it takes. So that is why I haven't pulled the head to check inside the cylinders. It would just be more mess to clean up and put back together if, unfortunately, I end up taking the car in to a shop.

So, I switched out my fuel pump thinking that it was a separate problem keeping the car from starting. When I tried starting again, it fired up but sounded kinda rough. I turned it off and let it sit for a while then went and pulled the fourth cylinder plug again. A decent amount of white smoke came out and the plug was fairly oily. I put a magnet down into the cylinder to see if it grabbed anything.

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That is what came out. Sorry for the fuzzy picture. The magnet is about a centimeter in diameter. And the stuff on it is metal fragments, all soaked in oil. What does this mean?

 

[Defiant]

You've jumped timing, possibly broken a valve, and now someone has put a fly fishing lure in your cylinder.

You have a broken engine, probably from a skipped timing belt. The first next step is to remove the head.