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Discussion Starter #1
Well, I am a happy camper now that I don't receive free massage from it each time I started it in the morning and move the gear from park to D or R, but I am experiencing some small vibration, particularly at high speed. Do I need new plugs?
 

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Did you use the uro brand TM from autohaus or did you get another one? Also did your mechanic align the MMs correctly, is everything torqued to spec? How old are the plugs, how many miles on them? How old is your maf? What condition the cats are?
 

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I believe the plugs are due at 100,000 miles although mine were still look very good when I changed them. However, 159k is pushing it, some may not fire right and you may also see decrease mileage? By the way, what's your mpg?

Also, check your wires, but most likely they should work fine.

JP
 

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Discussion Starter #8
I believe the plugs are due at 100,000 miles although mine were still look very good when I changed them. However, 159k is pushing it, some may not fire right and you may also see decrease mileage? By the way, what's your mpg?

Also, check your wires, but most likely they should work fine.

JP
I get about 14MPG in the city and 19MPG on the highway.
 

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I get about 14MPG in the city and 19MPG on the highway.
That seems too low, I can easily get 17mpg city and 26mpg on the highway (going about 75mph). Mine is a 98-E320 and has about 130,000 miles.

I think it's time you give it a tune up.
 

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Discussion Starter #10
Did you use the uro brand TM from autohaus or did you get another one? Also did your mechanic align the MMs correctly, is everything torqued to spec? How old are the plugs, how many miles on them? How old is your maf? What condition the cats are?
No, I ended up buying one from the dealer for $62. I don't know if the mechanic accurately aligned or torqued it. Is there a way to check this? Well, I just got the car so I don't know know how old the MAF and the CATs are. Also, I don't think the plugs ever got changed. I'll change the plugs first to see if there is a different.
 

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There are a handful of possibilities.

Certainly spark plugs are long past due, though if you bought it with more than 110K or 120K miles they may already have been done. Pull an easy one and check its condition.

O2 sensors are also a 100K item, though they are most often just ignored. As they get lazy they can subtly affect mixture. They can also shorten the life of the cats.

Clogged cats are classic for this as well.

Ignition wires out of range also contribute.

Your mileage is atrocious. If the plugs haven't been done I would proceed this way:

Change the plugs and while doing so, inspect and test the ignition wires. Replace any that are beyond spec. (They are costly so you can buy them individually, if more than six are shot then buy the set.)

All of the above is well within the ability of the casual DIYer.

If you still have the miss, then replace the front two O2 sensors (still a DIY job) and have the exhaust checked for backpressure (they can insert a sensor in place of the front O2 sensor to check). If you have excessive backpressure, replace the cats. Might as well do all four at that point as you can order them and bolt them in yourself, saving on the labor and then you don't have to try and figure out which one(s) are shot.

Good luck.
 

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Discussion Starter #12
There are a handful of possibilities.

Certainly spark plugs are long past due, though if you bought it with more than 110K or 120K miles they may already have been done. Pull an easy one and check its condition.

O2 sensors are also a 100K item, though they are most often just ignored. As they get lazy they can subtly affect mixture. They can also shorten the life of the cats.

Clogged cats are classic for this as well.

Ignition wires out of range also contribute.

Your mileage is atrocious. If the plugs haven't been done I would proceed this way:

Change the plugs, I still recommend the Beru NR plugs through rmeuropean.com. While you are changing them, inspect and test the ignition wires. Replace any that are beyond spec. (They are costly so you can buy them individually, if more than six are shot then buy the set.)

All of the above is well within the ability of the casual DIYer.

If you still have the miss, then replace the front two O2 sensors (still a DIY job) and have the exhaust checked for backpressure (they can insert a sensor in place of the front O2 sensor to check). If you have excessive backpressure, replace the cats. Might as well do all four at that point as you can order them and bolt them in yourself, saving on the labor and then you don't have to try and figure out which one(s) are shot.

Good luck.
Thanks.
 

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Discussion Starter #13
Change the plugs and while doing so, inspect and test the ignition wires. Replace any that are beyond spec. (They are costly so you can buy them individually, if more than six are shot then buy the set.)
I changed the spark plugs but still having a bit of vibration particularly at high speed. How do I check for bad spark plug wires?
 

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If the vibration is only at speed, very unlikely that it's related to the engine.

Flex discs and carrier bearing/bushing are a possibility, as well as numerous other suspension bits. I'd be looking under the car at this point, rather than under the hood. You would notice a wire issue more particularly at idle, especially creeping in gear.
 

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If the vibration is only at speed, very unlikely that it's related to the engine.

Flex discs and carrier bearing/bushing are a possibility, as well as numerous other suspension bits. I'd be looking under the car at this point, rather than under the hood. You would notice a wire issue more particularly at idle, especially creeping in gear.
+1 on this advice :thumbsup:
 

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Actually, Amoka, if you have not already done so, I would rotate the tires, just front-to-rear, keeping them on the same side. That's free other than a bit of time.

If the vibration changes in any way (better or worse) then have the tires balanced.

Good luck.
 
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