Weird vibration from 3200 to 3700

88-378

Member

Aug 10, 2007

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2

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Alpharetta, GA

Oct 7, 2011

#1

• Oct 7, 2011

• #1

Weird vibration from 3200 to 3700 - bad wires!!!

Like the title says. it is smooth to 3200 and smooth after 3700 Has anyone had a problem similar to this? I can pretty much rule out the drivetrain and suspension.

why would it only do it for 500rpm's?

I think it is a miss..ignition system?

what do you think? I am putting the car up next weekend to check out everything anyway. (my car is basically brand new front to back. it is fresh off a complete resto minus paint) I am almost finished with breaking the clutch in. could it possibly be the clutch not broken in yet?

 

Mustang5L5

That is…until I whipped out my Bissell

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Oct 8, 2011

#2

• Oct 8, 2011

• #2

I had the same thing happen. Since I did a 5-spd swap at the same time this happened, I assumed it was a balance issue.

Drove for a year living with it. Happened to check codes one day and did a cylinder balance test and discovered cylinder #4 was dead. To make a long story short, the injector was completely dead. I drove around for over a year on 7 cylinders and didn't even realize it.

 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor

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Oct 8, 2011

#3

• Oct 8, 2011

• #3

Does it vibrate only while under power or does it also do it when coasting?

 

88-378

Member

Aug 10, 2007

14

2

16

Alpharetta, GA

Oct 8, 2011

#4

• Oct 8, 2011

• #4

it does it a little while coasting. not as bad as when I am on the gas.

It doesn't shake the car either. so it's not that viloant of a vinration, but is noticeable.

 

88-378

Member

Aug 10, 2007

14

2

16

Alpharetta, GA

Oct 8, 2011

#5

• Oct 8, 2011

• #5

Mustang5L5 said:

I had the same thing happen. Since I did a 5-spd swap at the same time this happened, I assumed it was a balance issue.

Drove for a year living with it. Happened to check codes one day and did a cylinder balance test and discovered cylinder #4 was dead. To make a long story short, the injector was completely dead. I drove around for over a year on 7 cylinders and didn't even realize it.

Click to expand...

I guess I will be testing a few things. I plan on putting new plugs in, so I will see what that tells me.

 

BlackGT89

Member

Dec 16, 2002

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Huntsville, AL

Oct 8, 2011

#6

• Oct 8, 2011

• #6

If it's related to engine RPM maybe your harmonic balancer is starting to go ?

 

Mustang5L5

That is…until I whipped out my Bissell

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Feb 18, 2001

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Oct 8, 2011

#7

• Oct 8, 2011

• #7

Do a cylinder balance test as part of checking the engine running codes. It will tell you if you have a misfire

 

88-378

Member

Aug 10, 2007

14

2

16

Alpharetta, GA

Oct 8, 2011

#8

• Oct 8, 2011

• #8

I have a code reader and a book. I also need to get it back down to Atlanta Chassis dyno. I need it checked.

hold up. I think i have a bad wire. So i guess i have been running on 7 cylinders....LOL

 

88-378

Member

Aug 10, 2007

14

2

16

Alpharetta, GA

Oct 10, 2011

#9

• Oct 10, 2011

• #9

Well, well, well.

Had a bad wire. Just ordered a new set.

 

BlackGT89

Member

Dec 16, 2002

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Huntsville, AL

Oct 10, 2011

#10

• Oct 10, 2011

• #10

Glad you found it !

 

88-378

Member

Aug 10, 2007

14

2

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Alpharetta, GA

Oct 10, 2011

#11

• Oct 10, 2011

• #11

thanks. just hope i didn't damage anything. rings, piston, valves, etc...

A good friend and shop owner was messing with me telling me I need to re-ring that cylinder.... then he started laughing. He said it should be fine...

 

Mustang5L5

That is…until I whipped out my Bissell

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Oct 11, 2011

#12

• Oct 11, 2011

• #12

Glad you found it. You probably weren't 100% dead onthat cylinder, so i wouldn't worry.

When i put a new injector in, felt like i gained 50HP.

 

88-378

Member

Aug 10, 2007

14

2

16

Alpharetta, GA

Oct 11, 2011

#13

• Oct 11, 2011

• #13

Mustang5L5 said:

Glad you found it. You probably weren't 100% dead onthat cylinder, so i wouldn't worry.

When i put a new injector in, felt like i gained 50HP.

Click to expand...

You did! If i take my 405 at the crank, divide it by 8 and you get 50hp! LOL

It was probably my fault when i repaired a wire. Their must have been another small cut in it somewhere. I have a new set of FRPP wires coming. Plus i was getting crazy readings from my ohm meter.

Went to black wires for a more sinister look!

 

88-378

Member

Aug 10, 2007

14

2

16

Alpharetta, GA

Oct 12, 2011

#14

• Oct 12, 2011

• #14

New wires in. ran codes and a balance test.

All is good.