Looking for ideas on how to diagnose a knock/ rattle on a 91 SWB RRC that I am considering purchasing.
The RRC has 140K miles on it and the cats appear to be original, the current owner has all of the receipts from new including the original windows sticker and I could not find any mention of the original catalytic converters being replaced.
When first started (warm start) I do not hear the knock but after the RR sits for a little while (1-2 min) I can hear a knocking noise. The noise appears to be coming from under the front doors and you can not hear it from the rear or front of the vehicle. If I press on the accelerator the noise appears to go away and comes back once the RR is back at idle.
There are no dummy lights on other than the ABS, oil appears to be clean and I have really put my foot into it while driving it and the motor seems to hold together and pull well.
Anyhow I remember hearing a friends disco making a similar noise and it was his catalytic converters but I just want to try and isolate the issue prior to spending the $$ on this thing.
Do you think a stethoscope would isolate the noise enough or is there another way to tell if it is the Catalytic converters short of pulling them?
Thanks!
The RRC has 140K miles on it and the cats appear to be original, the current owner has all of the receipts from new including the original windows sticker and I could not find any mention of the original catalytic converters being replaced.
When first started (warm start) I do not hear the knock but after the RR sits for a little while (1-2 min) I can hear a knocking noise. The noise appears to be coming from under the front doors and you can not hear it from the rear or front of the vehicle. If I press on the accelerator the noise appears to go away and comes back once the RR is back at idle.
There are no dummy lights on other than the ABS, oil appears to be clean and I have really put my foot into it while driving it and the motor seems to hold together and pull well.
Anyhow I remember hearing a friends disco making a similar noise and it was his catalytic converters but I just want to try and isolate the issue prior to spending the $$ on this thing.
Do you think a stethoscope would isolate the noise enough or is there another way to tell if it is the Catalytic converters short of pulling them?
Thanks!
