Do Not Sell My Personal Information Jump to content

Coolent Leak

Recommended Posts


I am new to this forum

I own a IS200 sports 05 model.

I have recently spent some money on my car e.g. replaced water pump, changed full timing belt kit. My car has only done 67,000 miles.

Today i was hanging out with a few boys and listening to music with my engine turned on, all of a sudden we could smell something and saw smoke coming out of bonet on passenger side.

I opened the bonet and saw coolent leaking from radiator cap.

After waiting for a while i topped up the coolent thinking the cap might have been loose, i drove for about 25 minutes and was waiting in tesco car park while my mate used the cash machine, again standing in a steady position for 10 minutes we could see smoke from the bonet..My coolent is leaking and i am not sure what the problem is

Please help, Any advice people?

Link to comment
Share on other sites

I'm no expert but it sounds to me like the coolent is over heating, most probly your thermostat is the problem.

When steam/smoke was comming from under the bonnet was your temperature gauge working normally or did it show an abnormal temperture (very high or very low) and did the radiator feel hot or cold (if you checked). If the temperature gauge was very high and/or the radiator was very hot did the radiator fan switch on?

Link to comment
Share on other sites

As above sounds like the thermostat is staying closed and no water is circulating roound the rad to be cooled.

Or when it gets warm do the fans kick in, they might have forgotten to reconnect the fans. You need to get it sorted asap as overheating can lead to a failed head gasket as well

Link to comment
Share on other sites

Might be an idea to ask one of those radiator replacement firms to look at it. There is not much they don't know about cooling systems and the problems with particular models. If the worst comes to the worst and you need a radiator replacement they can fit a recon unit for less than main dealers. Radiators are often common to a number of vehicles. My son needed a replacement for his Civic. Cost him £80, parts, labour and fresh coolant.

Link to comment
Share on other sites

Today i have replaced the radiator cap and it seems to have solved the problem. Just hope it stays this way.

Yes the fans do come on...Thermostat staying closed?? No lights come on and temperature is normal.

what checks can i carry out to make sure everything is in working order?

Link to comment
Share on other sites

Make a note of your coolant level with the engine cold. Go out for a run, 10 miles. Make sure the heater works and confirm that the temp guage reads normal. Leave it to go cold and recheck coolant level. If it is the same, then no problem. If it has gone down then there is a leak. Recheck when cold over a few days.

Sounds as if the radiator cap was your problem. Cheap fix.

Link to comment
Share on other sites

Latest Deals

Lexus Official Store for genuine Lexus parts & accessories

Disclaimer: As the club is an eBay Partner, The club may be compensated if you make a purchase via eBay links

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


Lexus Owners Club Powered by Invision Community

eBay Disclosure: As the club is an eBay Partner, the club may earn commision if you make a purchase via the clubs eBay links.

DISCLAIMER: is an independent Lexus forum for owners of Lexus vehicles. The club is not part of Lexus UK nor affiliated with or endorsed by Lexus UK in any way. The material contained in the forums is submitted by the general public and is NOT endorsed by Lexus Owners Club, ACI LTD, Lexus UK or Toyota Motor Corporation. The official Lexus website can be found at
  • Create New...