Engine rattle w/slippage

[tjw1276]

Hey guys. Got a question for you, it's about rattling again, but with slippage. My 91' 240sx always had slippage sometimes when I engaged the clutch so I had it replaced. It didn't fix the problem, so I took it to the shop. Well, they had it for about 2.5 weeks and couldn't make the car slip not one time and said the clutch was put in well and didn't need to be blead. I also had them check the timing chain, but they found no problems with it. Well, now they are telling me to take it to an engine specialist because they believe that the rods at the bottom of the engine may be going bad and causing the rattling noise that I'm hearing. It drives excellent otherwise.

Has anybody else ever heard of this happening. I want to take it there but They are saying it could cost as much as a new engine, so what should I do. I would try to do it myself, but I don't have that much experinece with, and don't really want to go that deep into the engine, what do you think?

[Nismo_Freak]

Hard to say without listening to it. Typically rod bearings make a rattle when you are getting on the throttle at low rpms (2000 - 3000) when they start to wear. Full blown it's a loud pronounced knock noice.

See if the rattle sounds like it's coming from the upper area of the engine around the valve cover. If this is the case then an upper tensioner is more than likely the problem.

As for the slippage, are the RPM's suddenly going up faster and the car isn't moving, or does it just feel like the car isn't moving and the RPM's are staying the same / moving normally?

[Maverick7687]

I also have a problem with a rattle in my '93 240 but it sounds more like the exhaust heat shield missing a bolt..it looks like they are all there to me.. or the fan is hitting something..but the thing is it only does it at 1500 and 2000RPM exactly..like if I want it to do it I have to hold the revs dead on 1500..no other...anyone have any ideas on what that is..I have a little slip but my clutch is going bad..so I know what that one is. Any help would be great..i hope it is nothing internal...thanks, Mav

[Eastcoast Wildboy]

Hole in the exhaust system may cause that noise. The only was i know of slipping in that model was if u dont change gear oil or u have a bad transmission.

[Maverick7687]

Good...I was kinda gettin paranoid about it...I hope thats all it is...there is also a ticking soind from the front part of the valve cover..not sure what that could be but everything seems to run alright so far...hopefully nothing to worry about...I may be able to post sound clips of what it sounds like later...not sure how though

[tjw1276]

When the car slips, the engine revs up to around 5000 rpms then slowly revs back down as the car picks up speed.The rattling sounds like it's coming from somewhere behind the fan, and it only rattles a idle about 750RPMS, it goes away when the engine gets up to about 1500RPMS.

[Eastcoast Wildboy]

Bleed ur clutch see if thats whats wrong with the slipping.