Mechanics

SATURN VUE COMPRESSION PROBLEM

2005 Saturn Vue • 90,000 miles

Just installed a new head and when finished I started the engine and it now has a miss, it is on # 4 cylinder, already replaced ignition control module, plugs, and injector, what else should I look for?
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Jgable04
November 19, 2012.




You're going to have to go back and do some basic testing to determine whether it's spark, fuel or compression that you are losing.

Wrenchtech
Nov 19, 2012.
I'm getting power to the injector and I can hear it clicking on and off, I'm getting power to the plug but I'm not sure how to check to see if the plug is firing, I have not done a compression check where would I do this?

Tiny
Jgable04
Nov 19, 2012.
Go to our home page under the DIY section to see how to check for spark.

Also the check engine light comes on but when I try to pull codes there are none, the code reader is working properly I checked it on my 2005 malibu, why would this happen?

Tiny
Jgable04
Nov 19, 2012.
I would pull the coil pack off then remove all the spark plugs put them back in spark plug boots then plug in the ignition module touch the plugs to the valve cover crank the engine and see if all the spark plugs have a nice blue spark while cranking if the number 4 plug doesnt have spark but the rest do you have a bad coil. If all the sparks are good do a compression test. Also why dd you pull the head?Let me know what you find.

Saturntech9
Nov 19, 2012.
I have spark to all plugs but very little compression it seems the compression rings are bad, can this be repaired without pulling the engine?

Tiny
Jgable04
Nov 20, 2012.
Why did you replace the head?What are compression readings?How many miles does the engine have on it?I would suspect the cam timing or valves before the compression rings. Also when you installed the head did you get and install a new timing set with new tenisor guides sprockets chain cam bolts etc?Did you replace the cam sprocket bolts and retorque and torque angle them like your suppose too?
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Saturntech9
Nov 20, 2012.
Replaced head because of blown head gasket, have not put a gauge to the compression yet I just covered the spark plug hole and got little to nothing on it, around 90000 miles, only bad parts I had was the cam sprockets and bolts which I did replace, not sure what torque angle is I dont do this for a living so I hope im not in over my head.

Tiny
Jgable04
Nov 20, 2012.
You replaced the head just because the head gasket was blown?Or did the head get damaged also?I only replace heads if they get damaged. Also I always install a new timing set when pulling the head especially with that many miles on it. If you dont know what torque angle is you didnt tighten the cam sprocket bolts correctly. They take a certain torque and the a torque angle where you turn the bolt a certain amount of degrees. So does just the number 4 cylinder make little air while cranking or do the rest of the cylinders make little air also?You can rent a compression tester from auto zone. You need to do a compression test on the engine all of the cylinders you remove all the spark plugs then screw the tester hose into one cylinder at a time hold the gas pedal to the floor. Then crank the engine ten compression strokes you will feel when the engine kicks back on each compression stroke. Then write down the results of each cylinder with the low compression your next step will be to do a cylinder leak down test to see where the air is leaking.

Saturntech9
Nov 20, 2012.
Ok here is the deal the engine locked up and when I took it apart the back cam had eaten into the head and the gasket was blown thats why I changed heads, I did not install a new timing set, which now I guess I should have but the only damage that I could see was the sprocket teeth that fit into the end of the cam and the bolt were both broken so I replaced them, sorry I do know what torque angle is I just refer to it as degrees and I did torque it down and with the torque angle as well, 1, 2, and 3 put out plenty but 4 does not, now I have not put the gauge to them yet but as soon as I can this is next on my list.

Tiny
Jgable04
Nov 20, 2012.

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