On 11/17/10 1:44 PM, in article
,
"zofang7247" > wrote:

> Hello,
>
> I recently bought a used 1993 Nissan Altima as a daily driver.
> Yesterday, when I tried to fire it up, a huge cloud of black smoke
> came out of the exhaust and the car made this horrible sound.
>
> The car does not start anymore. When I try to start it, all I hear is
> this click/knocking sound in the engine bay area.
>
> If anyone can help me out as to what this might be I'd greatly
> appreciate it!
>
> Thanks!
>
>
> John McElroy

Might've slipped a cog on one of the timing chains (this car has an upper
and a lower). The upper chain tensioner is operated by oil pressure and can
freeze up if the oil passage gets clogged. There was also a problem on this
engine with the chain guides (both upper and lower) disintegrating.

If your problem is the upper chain, it can be easily repaired. The lower is
a major job. However - quit trying to crank it. You're probably smacking
valves into piston heads.