Engine temps are down slightly after lower grill block?

[YukonCornelius]

This is surprising. I blocked the giant hole on my Accord this Saturday then did a 50 minute drive in heavily traffic lighted territory. I believe it was the hottest day we've had this year. I was with my g/f so the car and a/c stayed on almost all of the time, expect for some sneaky EOC. The a/c suffered some from the block, which I expected. What I didn't anticipate was to see my temp gauge just a hair/fraction lower than where it would normally be. Today a trip to Philadelphia showed the same slightly lower temp. Any thoughts on why this is?

[MetroMPG]

Interesting. But I'd be reluctant to trust the accuracy of the dash needle, if that's what you're going by.

A ScanGauge or equivalent would give you a much better indication with a numeric read out plus the saved "max" value for the current trip.

[user removed]

In most AC systems you will have an electric fan, or both fans, running all the time when you have the AC turned on. In general those fans are located behind the radiator and pull air through the condenser and the radiator, thus the lower coolant temperature.

regards
Mech

[RobertISaar]

yeah, both A/C usage and known to be inaccurate/intermittent coolant temp guages would make this kind of behavior noticable.

if you're convinced the dash guage is correct, go steady-state at a decent speed(~50-70 MPH would be a good target), with the engine up to full temperature, engage A/C for a couple of minutes, then turn it off for a couple of minutes. see if there is a noticable change on the guage.

[Diesel_Dave]

I wouldn't make too much of it unless you can actually quantify it.

Are you saying you're warm up happens more slowly, or that you're final operating temp is lower? A grille block can potentially slow warm up a little because the engine doesn't have to work as hard. That being said, I would think the effect would be really small.

[AbeisAverage]

I recently put a grill block on my accord and I noticed a rise in the temperature. The car's temp gauge didn't even move from it's normal place just below the middle. But the scangauge reads temps at around 200-211, before installation I was getting 185-193 on the scangauge. I understand that it's a small difference, but I'd like some peace of mind on the matter. It shouldn't cause a problem right?

[YukonCornelius]

Originally Posted by Diesel_Dave

I wouldn't make too much of it unless you can actually quantify it.

Are you saying you're warm up happens more slowly, or that you're final operating temp is lower? A grille block can potentially slow warm up a little because the engine doesn't have to work as hard. That being said, I would think the effect would be really small.

I can't quantify it unfortunately, the car is OBD1 so I can't get a quick answer. I was talking about final operating temp.

[YukonCornelius]

Originally Posted by AbeisAverage

I recently put a grill block on my accord and I noticed a rise in the temperature. The car's temp gauge didn't even move from it's normal place just below the middle. But the scangauge reads temps at around 200-211, before installation I was getting 185-193 on the scangauge. I understand that it's a small difference, but I'd like some peace of mind on the matter. It shouldn't cause a problem right?

I wouldn't worry about that all. They put a dead spot in the gauge in what is the normal range. If you notice it moving up past normal then you'll know when it's getting too hot.

[redpoint5]

Originally Posted by AbeisAverage

I recently put a grill block on my accord and I noticed a rise in the temperature. The car's temp gauge didn't even move from it's normal place just below the middle. But the scangauge reads temps at around 200-211, before installation I was getting 185-193 on the scangauge. I understand that it's a small difference, but I'd like some peace of mind on the matter. It shouldn't cause a problem right?

With my upper grill entirely blocked, and the lower 3/4 blocked, my temps will hit 212 and the cooling fan kicks in. This is too much blockage in my opinion. I'm ok with temps reaching to 200 occasionally, but I'm not comfortable with sustained travel above that temperature.

If the car were more reliable and efficient at a higher temperature, the manufacturer would have installed a higher temp thermostat.

[Diesel_Dave]

Originally Posted by Lbar

I was talking about final operating temp.

Your thermostat should be the only thing that determines the final operating temp.

There should be only 2 exceptions:
1) Conditions are too cold and/or efficient to ever get the thermostat to open.
2) The vehicle's heat rejection capability has been comprimised and/or engine heat has been increased to the point where the thermostat is fully open and the engine is on it's way to overheating.