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Running on 7?

  • Thread starter Thread starter Synned
  • Start date Start date Jun 25, 2006
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Synned

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Mar 31, 2005
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Philly
Jun 25, 2006
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  • Jun 25, 2006
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My car is shaking badly, I replaced the balancer and I'm glad I did because the rubber was coming out of the stocker, however I still have the bad shaking.

I did a cylinder balance test, and #2 came up weak. I haven't had a chance to do much testing, but im confused. Sometimes the car runs perfect (like right after I changed the balencer.) I went home and went to drive to work and the damn shaking is back.
I unplugged #2 from the cap, and the car runs pretty much the same.
I guess I should try switching the wire, and then seeing if there is spark.
If I have spark, then its the injector? Can you buy just one injector? What else could it be? I also got the code that I'm running lean in the o2's.
 

bill302

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Nov 2, 2005
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alabama,gadsden
Jun 25, 2006
#2
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you can run a compression test this will tell you if the problem is within the cylinder...but it could also be a bad sparkplug or plug wire...and you will also need to check your fuel pressure and post results...and we can go from there.but i would change out the plug first and you can test the wire by useing it on another cylinder (plug) and see if it does the same thing on a different plug...
 
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Synned

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Philly
Jun 25, 2006
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Do you really think its compression? This happened out of nowhere....im just so upseet...
 

bill302

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alabama,gadsden
Jun 25, 2006
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i would think it was a bad plug or wire....but if the plug or wire does'nt help i would run a compression test...
 
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Synned

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Philly
Jun 25, 2006
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Just took the plug out and grounded it to see if there was spark, there was. It was firing, and I tried a different wire.

So you think I should run a compression test? I ran the balance test again and it came up 2, again. I didn't try switching the plug, incase the gap was way off or something.
I guess I'll go get some seafoam to maybe clean out the injectors.
I really dont want it to be compression.......
 

jrichker

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Looks like you are already heading in the direction I was going to suggest. A compression test is next.

Do a compression test on all the cylinders.
Take special note of any cylinder that shows up as weak in the cylinder balance test. Low compression on one of these cylinders rules out the injectors as being the most likely cause of the problem. Look at cylinders that fail the cylinder balance test but have good compression. These cylinders either have a bad injector, bad spark plug or spark plug wire. Move the wire and then the spark plug to another cylinder and run the cylinder balance test again. If it follows the moved wire or spark plug, you have found the problem. If the same cylinder fails the test again, the injector is bad. If different cylinders fail the cylinder balance test, you have ignition problems or wiring problems in the 10 pin black & white electrical connectors located by the EGR.

How to do a compression test:
Only use a compression tester with a screw in adapter for the spark plug hole. The other type leaks too much to get an accurate reading. Your local auto parts store may have a compression tester to rent. If you do mechanic work on your own car on a regular basis, it would be a good tool to add to your collection.

With the engine warmed up, remove all spark plugs and prop the throttle wide open, crank the engine until it the gage reading stops increasing. On a cold engine, it will be hard to tell what's good & what's not. Some of the recent posts have numbers ranging from 140-170 psi. If the compression is low, squirt some oil in the cylinder and do it again – if it comes up, the rings are worn. There should be no more than 10% difference between cylinders. Use a blow down leak test (puts compressed air inside cylinders) on cylinders that have more than 10% difference.
 
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Synned

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Philly
Jun 25, 2006
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Where can I order an injector from, the dealer? Can you buy one at a parts store? lol.

Would it be easy to swap injectors from #1 and #2? I can see them both, but I guess I have to take the fuel rail off and everything.
 

bill302

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alabama,gadsden
Jun 25, 2006
#8
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also buy a plug and replace just because it sparks don't mean its working properly it can have a weak or bad spark and be breaking down with heat ect....and a compression test....and check fuel pressure don't rule out a bad o2 sensors...and seafoam will help.
 
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Synned

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Philly
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bill302 said:
also buy a plug and replace just because it sparks don't mean its working properly it can have a weak or bad spark and be breaking down with heat ect....and a compression test....and check fuel pressure don't rule out a bad o2 sensors...and seafoam will help.
Click to expand...

But, would fuel pressure and bad o2 sensors just cause a problem on ONE cylinder? Thats what I don't get. It repeatedly comes up #2 in a balance test.
Im so upsetttttt.
Tomorrow I will run a compression test, im crossing my fingers its not compression, ill have to sell the car.
The engine only has 60k on it.

Where do I buy a single injector from?
 

fidstang

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Jul 19, 2005
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Jun 25, 2006
#10
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You can swap injectors without having to take the upper plenum and rails off. Just remove the connectors, remove the rail bolts and wiggle the injectors turning them so they pop out of the rail. Then turn and wiggle them out of the lower plenum. It will take time and patients but it can be done.
 

HISSIN50

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#11
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Joe (Synned), follow everyones' advice and toss your compression tester on that cylinder and see what it does. If you dont have a tester, it'll be a nice addition to the tool box.

And grab a new plug for giggles.

Good luck.
 

bill302

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alabama,gadsden
Jun 25, 2006
#12
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wal mart has a compression tester for about $20 in the automotive section next to the sparkplugs.
 
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Synned

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Okay good news, I had an auto stethescope so we checked for the clicking at the injectors. Injectors 1 and 3 had a very defined clicking, I could hear it perfect, but 2 had a very muffled almost inaudblie clicking.

So how can we test voltage without a noid light? Parts stores are closed now. Can we just use a multimeter?

Thanks guys
Joe
 

HISSIN50

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Joe, the injector gets 12 volts with the key on. The ground pathway comes from the drivers in the puter.

I think an LED test light might work to check this, or a regular test light (it might flash so fast it looks like it's almost lit constantly, like a pulsar star).
 
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Synned

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Philly
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#15
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HISSIN50 said:
Joe, the injector gets 12 volts with the key on. The ground pathway comes from the drivers in the puter.

I think an LED test light might work to check this, or a regular test light (it might flash so fast it looks like it's almost lit constantly, like a pulsar star).
Click to expand...

Well, the first thing we did was try to use the injector harness from #1 to see if we had clicking at injector #2, to see if it was the injector. It then clicked, even though it was the wrong firing order. So the injector is almost eliminated from this.
So I guess its either the injector harness plug thing or wiring to the PCM?
I hope I don't have to trace the wires...
Any suggestions? I'm going to get a noid light tomorrow and see whats up.
Im just glad its not a compression issue.

Forgot to mention- we tested the voltage on both harnesses- both had around 17 Volts on one connector and like .01 on the other.
Its weird...
 
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Synned

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ttt...pleaseeee
 

HISSIN50

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Synned said:
Forgot to mention- we tested the voltage on both harnesses- both had around 17 Volts on one connector and like .01 on the other.
Its weird...
Click to expand...
Any chance that wires are pinched from any recent work? I have absolutely no clue how you could get those readings (is your meter good?). I know when I'm gonna be more useless than normal and this is one time. I betcha that JRichker has some thoughts for ya though.

Good luck bud.
 
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Synned

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Mar 31, 2005
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Philly
Jun 26, 2006
#18
  • Jun 26, 2006
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HISSIN50 said:
Any chance that wires are pinched from any recent work? I have absolutely no clue how you could get those readings (is your meter good?). I know when I'm gonna be more useless than normal and this is one time. I betcha that JRichker has some thoughts for ya though.

Good luck bud.
Click to expand...

I have no clue. We used the batterie's ground though, and we unplugged the injector and used a digital multimeter. We didnt try to use both prongs on one harness to see if we got 12v, we just checked for power, with using a different ground.
 

jrichker

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Synned said:
I have no clue. We used the batterie's ground though, and we unplugged the injector and used a digital multimeter. We didnt try to use both prongs on one harness to see if we got 12v, we just checked for power, with using a different ground.
Click to expand...
You used the correct method to test the injector voltages. The .01 volt reading was probably the computer side of the wiring, and that's OK. The red wire is supposed to read whatver voltage is available with the meter leads directly on the battery posts. If you get 17 volts across the battery post either your meter is off or your voltage regulator needs to be replaced. Replace the batteries in your meter before you get upset & excited about the 17 volt reading you got.
 
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Synned

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Philly
Jun 26, 2006
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Well why wouldnt the injector fire with its own harness if its receiving the correct voltage but not when we used #1's harness?
Today I will try using the batterie's voltage and the injectors ground with a test light and see if that works, I'll also be getting a noid light.

What would cause the PCM to not fire that injector? Just a wiring short or problem?
Is it possible the PCM needs to be replaced...?
Do all the injector ground wires go directly to the PCM?
Thanks guys
Joe
 
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