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Old Mar 13, 2007 | 09:17 PM
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Default Here I go again....

Picked Y2K Vert up at shop today after they replaced both differential seals. Took her for a spin and the...

1. noticed my average MPG reading on the DIC began to count down while I was sitting at a red light. Can't say I ever noticied it doing that before??? I ran it on interstate and got the average up to over 22 MPG. But, it began to drop a tenth every 15 seconds or so. Crazy!! Anyone experienced that problem?

2. coolant temp climbed to 214 while I was sitting at another light. (70 degrees outside tonight...so, not too hot.) Why? No coolant problems before. Too hot to check coolant levels right now. Will check later. (Motor did not sound hot when I popped hood. You know...those little sounds an overheated motor makes??)

All other guages seem fine. Tranny fluid at 200 degrees (I think). Battery at 14. Oil temp was 212. Car ran strong on the highway and even on side roads.

LT
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Old Mar 13, 2007 | 09:28 PM
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For what it's worth, (my opinion, that is), what you've mentioned all seems pretty normal to me.

It only stands to reason if you are sitting still while the motor is running, the "average MPG" is going to count down, as you say.

And the coolant temps are about what it should be while you are "counting down" sitting at a traffic light.

Normal, that is, if you have the stock t-stat. Have you checked your rad for debris, lately? That might make it run a little warmer than you think it should.
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Old Mar 13, 2007 | 10:07 PM
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Originally Posted by MagikDraggin
For what it's worth, (my opinion, that is), what you've mentioned all seems pretty normal to me.

It only stands to reason if you are sitting still while the motor is running, the "average MPG" is going to count down, as you say.

And the coolant temps are about what it should be while you are "counting down" sitting at a traffic light.

Normal, that is, if you have the stock t-stat. Have you checked your rad for debris, lately? That might make it run a little warmer than you think it should.

Yep...checked rad for debris. Nothing noted. Checked fan: came on at 226 degrees and cooled it to 217...then it quit. Tested at idle in driveway. Checked coolant levels and all appeared o.k.?

My experience with this car has been max temp of 195 no matter where I was...but, it was in cooler weather? I have never once seen the MPG countdown while at a light. Seems to my non-mechanic mind to be an awful lot of fuel consumption at idle for a 3 minute light??

LT
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Old Mar 13, 2007 | 10:34 PM
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Default Was the MPG reset?

If the DIC was cleared the MPG will adjust very quickly at first. It will tick down at a light.

Everything else you mentioned seems ok also.

Bob K.
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Old Mar 14, 2007 | 08:56 AM
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Ever since I got my tune, my average MPG counts down at idle. FAST. Probably just pouring raw gas out the tailpipe. I wouldn't consider it abnormal behavior, but maybe not optimal.
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Old Mar 15, 2007 | 08:40 AM
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Originally Posted by Bob K
If the DIC was cleared the MPG will adjust very quickly at first. It will tick down at a light.

Everything else you mentioned seems ok also.

Bob K.
Took her out again last night. 81 degrees outside temp. Coolant temp rose to 196 in traffic. That is what I am used to seeing. Went to dinner. Came out and outside temp had dropped to 75, Drove back home with coolant pegged at 223? This is most disconcerting. In any other car, I'd say the thermostat is sticking.
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