AW11 - oscillating idle and ruptured radiator tank.

**suss_the_sitch** · 17-10-2011, 06:31 PM

Car: '87 NA AW11 MR2

I went to start the car on the weekend, and noticed two things.

1) Once the car had warmed up a little, the idle started to oscillate between 1k ~ 2k RPM quite quickly, sounded quite disturbing. Upon driving the car for 5 minutes the idle went back to normal. Tried again on Sunday, the same thing happened. Any suggestions on what would cause this?
2) When I got home from filling the car up on Sunday I noticed coolant was pissing out of the radiator, a round hole had formed in one of the side tanks.

I'm not sure if 1 is related to 2. Any suggestions on where to get a replacement radiator from? I called Natrad and they claimed that they can't get any, even though Denso's website still lists it.

**domma_aw11** · 17-10-2011, 06:45 PM

Number 1 sounds like it could be a vacum leak?? It just hunts between 1k n 2k rpms?? Mines does that somtimes, but get a second opinion on that one becuase mine dnt warm up quicker...

**old_mr2** · 18-10-2011, 10:05 AM

air bubbles in coolant. Fixing your radiator and replacing coolant should resolve this.

aw11 radiator | eBay

**foamy** · 18-10-2011, 12:03 PM

How big is the round hole? Unless the brass tank has cracked?

**suss_the_sitch** · 18-10-2011, 05:59 PM

foamy: slightly smaller diameter than a AAA battery

old_mr2: thanks for the confirmation and ebay link!

**BenAw11** · 19-10-2011, 03:27 PM

yeah it sounds like air bubbles i had the same happen to mine when i first bought the aw11, once i fixed the radiator issue and did a proper bleed on the coolant system she runs perfect now.