Author Topic: dirty throttle body because of regular costco gasoline  (Read 3834 times)

econberkeley

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dirty throttle body because of regular costco gasoline
« on: March 29, 2017, 04:25:31 PM »
My 2012 Nissan Murano (most reliable suv in its' price range) with only 40k miles on it stalled couple of times in the middle of driving so I took it to the mechanic. He told me that throttle body is very dirty and asked me what kind of gasoline I use. I told him I pretty much always use regular gasoline at Costco. He suggested getting premium gasoline once a month preferably from Chevron or Shell to keep the throttle body clean. Did you guys have the same issue with your car? is there any other way to keep the body clean?

bobechs

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Re: dirty throttle body because of regular costco gasoline
« Reply #1 on: March 29, 2017, 04:32:25 PM »
Add a can of Seafoam to the gas tank every other fill up for a while.

Dave1442397

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Re: dirty throttle body because of regular costco gasoline
« Reply #2 on: March 29, 2017, 05:06:36 PM »
You can also just clean the throttle body yourself when you notice a problem.

https://www.youtube.com/results?search_query=throttle+body+cleaner


JLee

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Re: dirty throttle body because of regular costco gasoline
« Reply #3 on: March 29, 2017, 05:10:27 PM »
Fuel does not pass through the throttle body.  I have no idea how your mechanic is making the connection here.

Khaetra

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Re: dirty throttle body because of regular costco gasoline
« Reply #4 on: March 29, 2017, 06:15:33 PM »
Does your Murano have fuel injectors?  If so, then I would do as he suggested and run a Top Tier gas like Chevron, Mobile, BP, etc. as those have detergents that help those stay clean (not premium price though, just the regular stuff).  As far as the throttle body you can clean that yourself, although with such low mileage I don't see how it could be dirty:

https://mobiloil.com/en/article/car-maintenance/how-to-do-it-yourself/proper-throttle-body-cleaning-guide

Ankenystache

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Re: dirty throttle body because of regular costco gasoline
« Reply #5 on: March 29, 2017, 07:52:53 PM »
I agree with the low miles part. 40k is a very low mileage to start having those issues (first for everything though). I have had cars come in that had bad gas due to excess water getting into the tanks and reported the same conditions you did. Your mechanic probably did the fuel system cleaner to make sure while also putting in fresh gas. Most gas doesn't come from each individual company, it is all in a pipeline that gets pulled out at the stations, mixed with each stores additive pack, and then branded as their own. So your costco gas is essentially the same as the Chevron, with a different additives added in. I would try switching gas stations for a while and see if that helps. Also may be worth letting the manager at Costco know, dont expect compensation, just a friendly email/letter explaining your situation. It may be a issue that they don't know about.

Clean Shaven

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Re: dirty throttle body because of regular costco gasoline
« Reply #6 on: March 29, 2017, 08:43:41 PM »
Fuel does not pass through the throttle body.  I have no idea how your mechanic is making the connection here.
This.

Check your air filter, all connections between the box it sits in and the motor, all vacuum lines, PCV valve if the motor has one.

Gas has nothing to do with your dirty throttle body. Something else is going on.

And find a new mechanic.

Dicey

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Re: dirty throttle body because of regular costco gasoline
« Reply #7 on: March 29, 2017, 09:47:21 PM »
Fuel does not pass through the throttle body.  I have no idea how your mechanic is making the connection here.
This.

Check your air filter, all connections between the box it sits in and the motor, all vacuum lines, PCV valve if the motor has one.

Gas has nothing to do with your dirty throttle body. Something else is going on.

And find a new mechanic.
Just read the original post and this response aloud to DH. He agrees and wonders if econberkeley drives on dusty roads much. The throttle body is sucking in dirt from somewhere. How old is the air filter?

econberkeley

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Re: dirty throttle body because of regular costco gasoline
« Reply #8 on: March 29, 2017, 10:07:51 PM »
Mechanic told me that air filter is dirty. It was clean couple of months ago though. My wife drives it mostly on the highway so it is not a dusty road issue.

I will Get regular gas at chevron once in a while and change the air filter more often. Lets see what happens.

Thank you guys for all your insights. They were very helpful.

JLee

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Re: dirty throttle body because of regular costco gasoline
« Reply #9 on: March 29, 2017, 11:21:07 PM »
Mechanic told me that air filter is dirty. It was clean couple of months ago though. My wife drives it mostly on the highway so it is not a dusty road issue.

I will Get regular gas at chevron once in a while and change the air filter more often. Lets see what happens.

Thank you guys for all your insights. They were very helpful.

Costco has top tier fuel -- I seriously don't think that's a problem, especially not given the described situation.  Did you verify that the air filter was dirty? It's usually very easy to do - and an easy way to tell if someone is BSing you into paying for unnecessary service.

JLee

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Re: dirty throttle body because of regular costco gasoline
« Reply #10 on: March 30, 2017, 09:25:12 AM »
If by "premium gasoline" your mechanic meant high octane fuel - ditch the mechanic stat.  If by "premium gasoline" they just meant brand name, I'm indifferent on that suggestion.

High octane fuel has less energy and if your car is not designed for it will likely cause worse problems due to a less complete burn.

Dirty throttle bodies and gasoline:
Fact is that quite a few vacuum hoses are piped in and about the throttle body.  While gasoline is injected in the manifold near the cylinder head (or in some cases directly in the cylinder head), incomplete hydrocarbon burn could get into the vacuum hoses and muck up the throttle body.  The poster who suggested checking vacuum lines, PCV, etc is probably on the right track.

1.  Do you do a lot of short trips where the engine never gets to full operating temperature?
2.  Do you accelerate hard when the engine isn't fully warmed up?
3.  Do you let your car idle to warmup?  This is detrimental to good operation of the vehicle and could be a factor.  See related video: https://www.youtube.com/watch?v=xKALgXDwou4

PCV is crankcase ventilation, i.e. oil vapor (not gasoline). If you have exhaust or unburnt fuel running through vacuum hoses, you have a major unrelated problem.


JLee

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Re: dirty throttle body because of regular costco gasoline
« Reply #11 on: March 30, 2017, 02:12:39 PM »
If by "premium gasoline" your mechanic meant high octane fuel - ditch the mechanic stat.  If by "premium gasoline" they just meant brand name, I'm indifferent on that suggestion.

High octane fuel has less energy and if your car is not designed for it will likely cause worse problems due to a less complete burn.

Dirty throttle bodies and gasoline:
Fact is that quite a few vacuum hoses are piped in and about the throttle body.  While gasoline is injected in the manifold near the cylinder head (or in some cases directly in the cylinder head), incomplete hydrocarbon burn could get into the vacuum hoses and muck up the throttle body.  The poster who suggested checking vacuum lines, PCV, etc is probably on the right track.

1.  Do you do a lot of short trips where the engine never gets to full operating temperature?
2.  Do you accelerate hard when the engine isn't fully warmed up?
3.  Do you let your car idle to warmup?  This is detrimental to good operation of the vehicle and could be a factor.  See related video: https://www.youtube.com/watch?v=xKALgXDwou4

PCV is crankcase ventilation, i.e. oil vapor (not gasoline). If you have exhaust or unburnt fuel running through vacuum hoses, you have a major unrelated problem.

Yes, of course you are right.  Thanks for the correction.

Combustion by-products can, and do, however get past the rings on a cold engine and get into the oil where some incompletely combusted fuel can taint the oil.

Oil vapor can definitely gum up your throttle body and intake manifold.

It can, yes - oil analysis can report the fuel dilution of oil. It isn't a situation where the additional solvents in some gasolines would provide benefit, though. Intake valves, on the other hand... :-)

Dicey

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Re: dirty throttle body because of regular costco gasoline
« Reply #12 on: March 30, 2017, 08:36:51 PM »
Chiming in to say I think it's kinda crummy to blame Costco gasoline in your subject line (or anywhere for that matter), given that there is no actual evidence  of this. I realize that's what your mechanic said, but based on the input here (and from DH at home), I'd question his advice and/or change mechanics pronto.

rtrnow

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Re: dirty throttle body because of regular costco gasoline
« Reply #13 on: March 31, 2017, 06:57:30 AM »
If by "premium gasoline" your mechanic meant high octane fuel - ditch the mechanic stat.  If by "premium gasoline" they just meant brand name, I'm indifferent on that suggestion.

High octane fuel has less energy and if your car is not designed for it will likely cause worse problems due to a less complete burn.



The murano is a high octane recommended engine like most (all) nissian vq engines. The higher tune versions (g37) require high octane. You will probably get better mileage and performance with high octane in a murano.

techwiz

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Re: dirty throttle body because of regular costco gasoline
« Reply #14 on: March 31, 2017, 07:38:37 AM »
I agree with the others it is not likely Costco gas causing the problem. The cheap easy steps of checking the air filter and checking the lines are good ones. Also check the internet for any known issues. If you have access to a code reader you could see if there are any error codes.
 
P.S.
I had a similar issue with my car stalling on me and found online there was a recall for a defective throttle body (electrical issue). After bringing it into the dealer who confirmed the issue but could not honor the recall. I bought the part($140) and replaced it myself only 4 bolts and 15 minutes of my time. The car has been running great ever since.   

Best of luck.