Metalic popping sound at 3000 rpm

[Will Orum]

Hi All,

Another 1500 spit issue! Every time I hit 3K rpm, the engine makes this horrible metalic popping sound. It sounds just like pinking, i'm pretty sure it's not though as it goes away 100 rpm later. Engine doesn't pink when under heavy load either. 

It's done it while pulling away, while on the motor way, while going up hills. The only logical explanation I can think of is some kind of resonance at that specific rpm - it doesnt do it out of gear though. Any help would be appreciated!

 

 

 

 

[Pete Lewis]

think its exhaust fouls when engine torque tips the engine and the pipes foul the chassis 

Pete

[Will Orum]

That sounds like a pretty good theory. I'll have a look. Thanks

[Nigel Clark]

I also think it's an exhaust problem, most likely fouling on the chassis or diff carrier.

It's worth checking under the car for broken exhaust mountings and its alignment. While under there, have a good look for any witness marks indicating contact between exhaust and underside of the car.

Nigel

[Will Orum]

So I never really solved this issue. There were no witness marks anywhere, I was really scratching my head over it. That was until yesterday when I got caught by a nasty speed bump and knocked the exhaust. Problem is completely gone. Had a look under the car, all looks good apart from the slight scratch on the exhaust. 

I guess sometimes bad things aren't so bad...