Spark plug cleaning

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98beretta kid
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Location: Bay City, Michigan

Spark plug cleaning

Postby 98beretta kid » Mon Jan 20, 2003 5:13 pm

Lately my fuel mileage has been on a steady decrease. It used to be around 23 even 24 miles per gallon at times. Now im getting around 16-17 mpg. I was thinking if cleaning the sparkplugs with a small wire brush attached to a dremel would be worth the trouble? I was also thinking that maybe a cylinder isnt firing, how would i test something like this? Im open to all suggestions. I replaced the plugs and wires back in february and just had my oil changed about 400 miles ago. Its seems that since i had my oil changed, is when i first noticed the fuel mileage going down. I switched from Pennzoil to Quaker State High Mileage. Thats all i can tell at the moment. If i think of something else ill post. One last thing, i installed a new air filter when the oil change was done.


-Bryan

1989 Beretta GT (Money pit #1)
1996 GMC Sonoma (Money pit #2)
1993 GTZ ( Couldn't ask for a better Car)

The 3 reasons why I'm broke

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Spark plug cleaning

Postby Guest » Mon Jan 20, 2003 5:19 pm

Are the plugs dirty? Its probably better to just replace them (if they need it) if you can afford to at this time.

Is the car running any different? You can see if a cylinder isn't firing by using a pair of spark plug pliers to pull the plug wire off while the engine is running. Hold it close to the plug or any metal piece and look for spark.

When was the last time you changed your fuel filter?



Guest

Spark plug cleaning

Postby Guest » Mon Jan 20, 2003 6:41 pm

You would definitely know something was wrong if you had a cylinder not firing.  Unless your engine is chugging and you have about zero power, it's probably not that.  If you replaced your plugs and wires less than a year ago, you shouldn't have to do it again so soon.  Changing oil types shouldn't cause a major difference either.  What you may want to do, is replace your O2 sensor.  If it has gone bad-could be shorting out-replacing it can make a marked improvement in performance and mileage, as it did with mine.  

How does your engine run in general?  Does it ever stall or feel like it wants to?  If so, you may have a vacuum leak or a clogged fuel filter.  Fuel filters aren't that much...I think around $20.  

Just ask if you have more questions.

Mike
<><



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98beretta kid
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Joined: Sat Oct 13, 2001 2:59 pm
Location: Bay City, Michigan

Spark plug cleaning

Postby 98beretta kid » Mon Jan 20, 2003 7:41 pm

The o2 sensor was replaced around the same time the plugs were changed. The fuel filter was changed sometime in October. It may need to be replaced seeing as how i run the tank almost dry before filling up. The engine seems like it wants to stall when i first start driving, i have to hold the accelerator steady to keep her running, after that, it runs excellent. I was also thinking a plug wire simply came loose or maybe even a small fuel leak.


-Bryan

1989 Beretta GT (Money pit #1)
1996 GMC Sonoma (Money pit #2)
1993 GTZ ( Couldn't ask for a better Car)

The 3 reasons why I'm broke

Guest

Spark plug cleaning

Postby Guest » Mon Jan 20, 2003 10:30 pm

When was the last time you cleaned out your throttle body? Even if its not the problem here its something that should be done every once in a while.



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88GTRacer
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Spark plug cleaning

Postby 88GTRacer » Tue Jan 21, 2003 3:56 am

I would suggest you start checking the condition of your emissions system. 88GTRacer


"It is one of the most beautiful shapes on the road. Aero, alluring and very aggressive.
It is a Beretta, the new performance coupe from Chevrolet."

Guest

Spark plug cleaning

Postby Guest » Tue Jan 21, 2003 5:21 pm

Hmm...Yeah, check your emissions system.  Maybe your catalytic converter is plugged.  Have you ever had that replaced?

If your mileage is that bad but your engine doesn't run rough, I'd say check your vacuum connections. ÂÂÂ A few years ago I noticed my fuel economy going down and down, and I had to give it more and more gas to keep up. ÂÂÂ It got so bad that it was jerking like crazy and stalling, and it acted like it was going to stall every time I'd take off. ÂÂÂ It turned out to be a hole in my EGR that was causing a huge vacuum leak. ÂÂÂ After that was fixed I couldn't believe the difference. ÂÂÂ It practically drove like new.  So maybe you could go that route. ÂÂÂ Hope this helps.

Mike
<><



Guest

Spark plug cleaning

Postby Guest » Tue Jan 21, 2003 5:53 pm

I am getting like 14 miles to the gallon, but i don't drive on the parkway, just to school, which is about 15 miles round trip. and to work and such other places.



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Kevskate99
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Spark plug cleaning

Postby Kevskate99 » Tue Jan 21, 2003 8:54 pm

Maybe since its winter I am guessing that you start the car before you get in it? And if so, there's your culprit. ;) I get about 25-28 during the summer and lately I've been getting about 20 and I only start it 10mins early in the morning and 10 mins early when I leave to go to work, so only 20 mins idling during the whole day but it makes a world of a difference.






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98beretta kid
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Location: Bay City, Michigan

Spark plug cleaning

Postby 98beretta kid » Tue Jan 21, 2003 9:37 pm

Quote (Kevskate99 @ Jan. 21 2003,19:54)
Maybe since its winter I am guessing that you start the car before you get in it? And if so, there's your culprit. ;) I get about 25-28 during the summer and lately I've been getting about 20 and I only start it 10mins early in the morning and 10 mins early when I leave to go to work, so only 20 mins idling during the whole day but it makes a world of a difference.

I have the digital gauge cluster thats says both the average mpg and the instant mpg. When ever im on the highway (twice a day) i reset the mpg gauge and watch it for a few miles. It always goes back to around the same area ??? Im pretty sure that the Catalytic (sp.?) converter is the original one. But would that make that much of difference? Sometimes when going in reverse i can smell this really bad exhaust smell. Is there any kind of cleaner for the catalyc converter? I just had a cat back exhaust put on in the summer and would hate to have to take it off to replace the catalyc converter. Today at school i had my car on the hoist and check the fuel line and fitting over and confirmed that there wasnt any leaks.


-Bryan

1989 Beretta GT (Money pit #1)
1996 GMC Sonoma (Money pit #2)
1993 GTZ ( Couldn't ask for a better Car)

The 3 reasons why I'm broke

Guest

Spark plug cleaning

Postby Guest » Wed Jan 22, 2003 5:41 pm

Did you ever fix the TCC solenoid or are you driving around with it unplugged?  That could be keeping your RPMs a little high on the highway.



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98beretta kid
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Posts: 46
Joined: Sat Oct 13, 2001 2:59 pm
Location: Bay City, Michigan

Spark plug cleaning

Postby 98beretta kid » Wed Jan 22, 2003 7:42 pm

Quote (css9450 @ Jan. 22 2003,16:41)
Did you ever fix the TCC solenoid or are you driving around with it unplugged?  That could be keeping your RPMs a little high on the highway.

I had that taken care of right after it went bad. Its plugged in and still working good. My rpms are around 3700 on the highway. I feel its pretty high.


-Bryan

1989 Beretta GT (Money pit #1)
1996 GMC Sonoma (Money pit #2)
1993 GTZ ( Couldn't ask for a better Car)

The 3 reasons why I'm broke

Guest

Spark plug cleaning

Postby Guest » Sun Jan 26, 2003 5:49 pm

How fast do you drive on the highway?  I have the digital cluster as well, and my RPM's read 3100 @ 70 mph.  I have a 2.8 w/ the 3-spd auto.  Unless you drive 80 mph or faster, 3700 sounds quite high, unless my guage is wrong.



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98beretta kid
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Posts: 46
Joined: Sat Oct 13, 2001 2:59 pm
Location: Bay City, Michigan

Spark plug cleaning

Postby 98beretta kid » Sun Jan 26, 2003 5:53 pm

Quote (nice89GT @ Jan. 26 2003,16:49)
How fast do you drive on the highway?  I have the digital cluster as well, and my RPM's read 3100 @ 70 mph.  I have a 2.8 w/ the 3-spd auto.  Unless you drive 80 mph or faster, 3700 sounds quite high, unless my guage is wrong.

Normally im doing around 74-75 on the highway.


-Bryan

1989 Beretta GT (Money pit #1)
1996 GMC Sonoma (Money pit #2)
1993 GTZ ( Couldn't ask for a better Car)

The 3 reasons why I'm broke

Guest

Spark plug cleaning

Postby Guest » Sun Jan 26, 2003 6:31 pm

Gee bryan, sounds like the tcc is not connected internally. I know that most of the replacement ones come with an enclosed anti fire igniting type design, and they don't always make proper contact. When that happens, it's like having it unplugged, maybe this is what has happened.




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