Fuel Problem/ Poor Mileage

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Re: Fuel Problem/ Poor Mileage

Post by Roadhog »

FutureStage1 wrote:How can you tell if your coolant sensor has gone bad? My car seems to be running like shit lately. Just noticeably sluggish

I think you can check the resistance of it... But its easier just to replace it for the $5 or whatever it is.
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Re: Fuel Problem/ Poor Mileage

Post by Mikewire »

Roadhog wrote:Use OEM, they work the best in a vr6.

Also, the blue has to do with the color of the sensor (somtimes they may be black). But this sensor is like an 02 sensor, though it tells the engine how hot the coolant is. A lot of times they go bad, and the engine never gets out of cold start mode (really rich).

There's one for the gauge, and one for the ECU btw. Which one was replaced?
Good call Spence. I can scan for temps - any idea what the running temp would be? 190?

Oh and Matt IIRC the coolant sensor you can get at Dana for a little over $20. And, it should be a green top, not blue top, although I think both will work - blue is made by the OEM manufacturer and the green is aftermarket. The black top is the older OEM version that goes bad often.

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Re: Fuel Problem/ Poor Mileage

Post by bigmontana »

My running temp is always half way on the guage i always figured 190 it has never gone above that. As far as what they replaced. I just told the dealer in Fargo to replace the coolant temp sensor I did not even think to ask him waht they replaced. It was after our trip to Missoula this past June and my CEL was one and when I scanned it it came up as a coolant temp sensor. I'll go to o'reily tomorrow and get platinum plugs and I'll get a new air filter and an oil filter. Hopefully this will help something and if not we can check this off my list of possible problems and after that replace the O2 sensor. Nothing has ever come up when we have scanned it though except for my coolant temp sensor and me MAF. Hopefully we'll be able to fix it this weekend. Thanks for the help.
When I get the fuel filter tomorrow I'll price an O2 sensor too.
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Re: Fuel Problem/ Poor Mileage

Post by Mikewire »

Oh I remember now - so you got that coolant sensor replaced? Ok, there is one coolant sensor commonly replaced in the thermostat housing - Spence wheres the second coolant sensor? Also Matt there are two O2 sensors, one is pre cat and one is post cat. IIRC the pre cat is cheaper.

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Re: Fuel Problem/ Poor Mileage

Post by 73veedubya »

could it be a fuel filter problem maybe? my GTI did that same exact thing to me once back from helena after a auto x except i was getting 11mpg. and as for doing someting for it just kinda came back to normal.
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Re: Fuel Problem/ Poor Mileage

Post by Rennwagen1 »

11MPG in you GTI?! That is awesome!! Why did you ever sell it??!!

Actually, I can't believe that nobody has mentioned either a plugged or bad cat. That would be something to check also.
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Re: Fuel Problem/ Poor Mileage

Post by 73veedubya »

Rennwagen1 wrote:11MPG in you GTI?! That is awesome!! Why did you ever sell it??!!

Actually, I can't believe that nobody has mentioned either a plugged or bad cat. That would be something to check also.
that is why i sold it :retard: :laughing: . seafoam cleans the cats also when you use it so that could be a possibility too
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Re: Fuel Problem/ Poor Mileage

Post by Roadhog »

Big Montana wrote:My running temp is always half way on the guage i always figured 190 it has never gone above that. As far as what they replaced. I just told the dealer in Fargo to replace the coolant temp sensor I did not even think to ask him waht they replaced. It was after our trip to Missoula this past June and my CEL was one and when I scanned it it came up as a coolant temp sensor. I'll go to o'reily tomorrow and get platinum plugs and I'll get a new air filter and an oil filter. Hopefully this will help something and if not we can check this off my list of possible problems and after that replace the O2 sensor. Nothing has ever come up when we have scanned it though except for my coolant temp sensor and me MAF. Hopefully we'll be able to fix it this weekend. Thanks for the help.
When I get the fuel filter tomorrow I'll price an O2 sensor too.
The coolant temp sensor I'm talking about has NOTHING to do with your gauge (idiot gauge, always shows 190 or jumps to max if it gets over like 230 or something). The sensor I'm talking about is for the ECU.
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Re: Fuel Problem/ Poor Mileage

Post by bigmontana »

I honestly can't tell you which temp sensor they fixed Spence, I don't know if it is one for the ECU or not. I know for m,y year VR6 there is two sensors a cheap one and an expensive one. I think the one they fixed on my wagon was the cheap one. So it could still be that, and thank you Aeron I never thought of the cat. I did buy Lucas Injector cleaner which I'll put in as soon as I need to fill up. I also got new Auto Lite Platinum plugs, a new air cleaner, and a new fuel filter, which we are going to install this weekend. Then I'll make another trip to Fargo and see fi these things helped and we'll try it again. Hopefully this fixes the problem. Does this sound like the right way to go. This what both Dana Motors here in Billings told me, you guys told me, and what MIG told me to staert with so I'l willing to try it. thanks for the suggestions
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Re: Fuel Problem/ Poor Mileage

Post by Roadhog »

sounds good except the fucking shitty ass auto lite plugs. get NGK's.
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