Coolant Light

[kevrod79]

Morning all,

Wife reported the coolant light came on on the dash of my Vectra this morning. 07 plate Exclusive 1.8. Level not dipped a huge amount. I take it I can top it up with a little water?

Kev

[WilliamLX]

This happened to me about 2 months ago. The level was only slight low, a few mls of water topped it up and while this may have slightly diluted the antifreeze I have had no problems so far even on -5 mornings. Worrying thing is the manual says this hould never need topping up. Not sure why my one did, although it was just after it had been in the garage getting its aircon repaired! Since then the level has not dropped at all.

[kevrod79]

reassuring to hear. I will top it up tonight when I get home. I got her to look at the line and she confirmed it was only slightly below it.

Kev

[Das]

Yea, while doing my thermostat yesterday the coolant light came on on mine, level was only about a 1/4 to 1/2 inch below the mark so defiantly normal. I would top up with straight antifreeze, remember its the Red OAT stuff and not the blue stuff.

[kevrod79]

OAT?

[Das]

Organic Acid Technology

Organic acid technology
Certain cars are built with organic acid technology (OAT) antifreeze (e.g., DEX-COOL[11]), or with a hybrid organic acid technology (HOAT) formulation (e.g., Zerex G-05[12]), both of which are claimed to have an extended service life of five years or 240,000 km (150,000 miles).
DEX-COOL specifically has caused controversy. Litigation has linked it with intake manifold gasket failures in GM's 3.1L and 3.4L engines, and with other failures in 3.8L and 4.3L engines. Class action lawsuits were registered in several states, and in Canada,[13] to address some of these claims. The first of these to reach a decision was in Missouri where a settlement was announced early in December, 2007.[14] Late in March 2008, GM agreed to compensate complainants in the remaining 49 states.[15]
There are rumors that mixing DEX-COOL with standard green (non-OAT) coolant causes a chemical reaction that produces sludge in the cooling system. According to the DEX-COOL manufacturer, however, "mixing a 'green' [non-OAT] coolant with DEX-COOL reduces the batch's change interval to 2 years or 30,000 miles, but will otherwise cause no damage to the engine."[16]
According to internal GM documents, the ultimate culprit appears to be operating vehicles for long periods of time with low coolant levels. The low coolant is caused by pressure caps that fail in the open position. (The new caps and recovery bottles were introduced at the same time as DEX-COOL). This exposes hot engine components to air and vapors, causing corrosion and contamination of the coolant with iron oxide particles, which in turn can aggravate the pressure cap problem as contamination holds the caps open permanently.[17]
Typically OAT antifreeze contains an orange dye to differentiate it from the conventional glycol-based coolants (green or yellow). Some of the newer OAT coolants claim to be compatible with all types of OAT and glycol-based coolants; these are typically green or yellow in color (for a table of colors, see [4])

http://en.wikipedia.org/wiki/Antifreeze

[Big Dave]

When you top it up, make sure the coolant level in the expansion tank is just slightly above the KALT/COLD mark (When the cooling system is cold) - as per mention in the handbook.

[kevrod79]

Checked it last night and it needed a tiny bit of antifreeze. Temp gauge is sitting where it normally sits. Will keep an eye on it.

Ta,

Kev