Intermittent Rad light warning

[spinalator]

RE: 99 alero 3.4L 134,000 km

Hi all, I bought this car in Sept with 100k on it, and after getting the stealer change a wheel hub speed sensor, it has behaved flawlessly for another 34K. I have started wrenching on this car myself since I now have a garage and have done Front and Rear rotors and pads, new sparkplugs, (ouch my knuckles) new paper air filter, oil change.

Now I get the engine trouble pic but no SES light. My 33 dollar scanner tells me there are 2 codes, both are P1404 EGR Closed Position Performance. One says pending what ever that is. I will clean the EGR valve and it will likely fix the problem, and will report back if it does not.

Soooo....

What is frustrating also is a weird intermittent light for the rad. It happens about once a week, and lasts from 25 seconds to a minute. My scanner can not find any stored codes regarding the rad. Antifreeze level is OK, no leaks. Fans appear to be coming on, as I often hear them.

Should I look for a sensor to clean? Wires that are wonky? Fan that is dying? Drive with the scanner angling from the dash and hit scan when the light turns on?

Thanks for any input!

[Midgear]

I'm assuming "rad" means Radiator? lol

how old is the fluid in it? if you dont know, might flush it out and top it off just to make sure everything is clean..

how hot does the engine run?

[spinalator]

I'm assuming "rad" means Radiator? lol

how old is the fluid in it? if you dont know, might flush it out and top it off just to make sure everything is clean..

how hot does the engine run?

Thanks for the reply. yeah I am too lazy to type radiator, lol.

Actually not sure how old the fuid is. The manual says it should be good for 100,000 miles, but I was thinking of a flush. Usually after taco night I am a double flusher, but for the rad I think once is enough... :lol:

[Redog]

Do a postive flush. a lot of flushing machines will go in the reverse direction of coolant travel which kills gaskets.

Do you know if the LIMG (lower intake manifold gasket) has been repiared by the prrvious owner? Do a search on this site, you'll see a lot a thread about it.

If the light is going on and off, it's probably just a little low. Just low enough to come on what you turn a corner or park on a hill facing upwards. Top it off and you'll be fine, just use Dexcool unless it's be converted

[Ryan from Ohio]

Add more fluid.

If this continues to happen you probably need a new lower intake manifold gasket!

[Vinalero]

Wasn't there some cases where the sensor in the fluid overflow tank went bad? This could be the problem.

[spinalator]

Thanks for the replies.

It happened again today for about 2 seconds. Darn light won't stay on so I can read the error code. Fluid is up, I can't see any leaks. Possibly a sensor issue, I will keep searching...