Bad valves guides or bad fuel injectors?

[plymouthcolt]

In September of 2007 I posted asking for help on diagnosing my spark plugs.

Please help diagnose my spark plugs

At that time #4 and #5 were fouled pretty bad.

Well I am now trying to track down why I have a lopey idle and loss of power. I did find a vacuum tube loose from the fuel pressure regulator, reconnected, but no improvement.

I don't know why but I pulled the plugs--I was just curious.

Lo and behold the plugs are exactly the same condition as last September. #1 to #3 and #6 look normal. Again #4 and #5 are fouled with oil.

Could I maybe have bad injectors on these two cylinders? At this point I'm inclined to send out all the injectors for testing and cleaning.

I know it can't be the wires, cap, or rotor as they are all new. I tested the coil and it is within specs.


Plugs 1, 2, and 3




Plugs 4, 5, and 6



Worse case scenario bad valve guides on two? 119,726 miles on the odometer. Using about a 1/2 quart every 600 miles

[stlrj]

Bad ignition cables would be my first guess.

[sig_a]

Howard: I recently replaced no. 6 injector where I went thru the same routine diagnosis as you. My no. 6 spark plug looked every bit as bad as your no. 4. My symptom was a below 3000 rpm miss which smoothed out above 4000 rpm. There is so much talk here about bad valve guides plaguing 3.2 liters, I suspected that as well. Mine ended up being a bad cylinder 6 electronic injector with no current. You may want to check all yours with a multi meter. More often than not, fouled spark plugs do not indicate bad valve guides.

[plymouthcolt]

Originally Posted by sig_a

Howard: I recently replaced no. 6 injector where I went thru the same routine diagnosis as you. My no. 6 spark plug looked every bit as bad as your no. 4. My symptom was a below 3000 rpm miss which smoothed out above 4000 rpm. There is so much talk here about bad valve guides plaguing 3.2 liters, I suspected that as well. Mine ended up being a bad cylinder 6 electronic injector with no current. You may want to check all yours with a multi meter. More often than not, fouled spark plugs do not indicate bad valve guides.

Thanks I have some noid lights I will try them out tomorrow and also test with the multimeter.

[PatrickB]

I'd go with getting the injector's rebuilt too! If they haven't been serviced in 20 years, you'll need to do them soon enough anyway. I had similar if not worse running issues than you, and a fresh set of injectors was like installing a brand new engine!! Also, much cheaper than a top end!

[afterburn 549]

To do a plug check means more then unscrewing the plugs......You could do a wobble feel on the valves and see what you get.
you could do a comp. test to see if there is a diff

[stlrj]

Originally Posted by stlrj

Bad ignition cables would be my first guess.

Sure you didn't cross your wires? Might check again.