Engine Clanking Noise When Driving

[Samuel Gertner]

I have a 2001 JOB 1. I started hearing a clanking noise when driving on a bridge or a roadway with a minor incline. It normally happens when the engine is running around 2K RPM. It is not a loud noise, but it is noticeable if you listen closely. Does anyone have any ideas on what could be causing this? Any help is GREATLY appreciated.



Thanks!

 

[Mike Wilson]

Spark Knock, If it happens with the engine under a light or moderate load, and

before the transmission downshifts, this is most likely the cause.



What type of gas (octane) do you use? May want to go up one (87 to 89

for example) and see if this helps.

 

[Samuel Gertner]

I have tried different octane fuels. I have used 87, 89, & 93 with the same results. I do have a Diablo chip installed if that makes a difference.

 

[Mike Wilson]

I'm not too much into chips (unless they come with salsa!), but that may

also be a cause. May need some tweaking in the programming.