plug reading experts please comment

TurboDave

RIP DAVE
Staff member
TurboBuick.Com Supporter!
Here's some pix, let me know what you think;

I pulled these after:
Idling in driveway. Idle was in gear so I could monitor my WBO2's in a stable state to adjust my two devices (TransPro, and Powerlogger) so the matched perfectly.
So with light load, and A/F ratio of 14.7:1
Then drove it into the garage and pulled 'em.

All the views are the same plugs, just slightly different agles to get good light.
 

Attachments

  • 100_0542.JPG
    100_0542.JPG
    55.2 KB · Views: 249
  • 100_0543.JPG
    100_0543.JPG
    24.6 KB · Views: 238
  • 100_0544.JPG
    100_0544.JPG
    54.2 KB · Views: 260
Dave,

Its very hard to read them at those angles. Best to get close ups of each individual plug, one from the side and one from the top looking in. The only thing I can see is #6 looks darker/richer.
 
How many miles? 6 is the only one that stands out ( maybe sticky injector?)

How many miles what? On the plugs? Wow, not sure, maybe 5-10K

I'll have to try and see if I can "screw driver stethescope" the injectors and make sure they all sound the same.

#6 is a little darker. Looks a lot darker than it really is in the pic.

I was surprised to see how nice and "white" all the rest were, after sitting at idle for so long.
 
Are you having an issue Dave? Or are you just pulling them to check mixture color?


To be perfectly honest, I was bored that day. Had gone out making sure my settings in the TransPro were keeping my INT's close to 128 (this tells me the closed loop system is close. I was sitting in the driveway idling, in gear, watching the powerlogger and Translator Pro WBO2 readouts (while the car was in closed loop control of the NBO2) to ensure that they're both seeing the same thing.

Even though the car has a mildly rich smell while idling, the plugs and WBO2 reading 14.7:1 +/- .4 tell me that all's well.
 
Even though the car has a mildly rich smell while idling, the plugs and WBO2 reading 14.7:1 +/- .4 tell me that all's well.

It's like I'm reading my own post. Mine look just like that. Including #6 as always being a little darker than the rest. My idle O2's are the same too.

What plug gap do you run??
 
To be perfectly honest, I was bored that day. Had gone out making sure my settings in the TransPro were keeping my INT's close to 128 (this tells me the closed loop system is close. I was sitting in the driveway idling, in gear, watching the powerlogger and Translator Pro WBO2 readouts (while the car was in closed loop control of the NBO2) to ensure that they're both seeing the same thing.

Even though the car has a mildly rich smell while idling, the plugs and WBO2 reading 14.7:1 +/- .4 tell me that all's well.

Its nice to reach that status of "being bored" with your Turbo Regal. Very few have ever ventured into that unknown area before. You know, when the car is running perfect and there is really no mods or money left to dump into it. You have to find something to do with it. Its not naturual to have a GN and not be turning a wrench or waiting for the UPS truck to show up.:D

I am in such a state right now...nothing to do on my car except waste the back tires.:smile:
 
To be perfectly honest, I was bored that day. Had gone out making sure my settings in the TransPro were keeping my INT's close to 128 (this tells me the closed loop system is close. I was sitting in the driveway idling, in gear, watching the powerlogger and Translator Pro WBO2 readouts (while the car was in closed loop control of the NBO2) to ensure that they're both seeing the same thing.

Even though the car has a mildly rich smell while idling, the plugs and WBO2 reading 14.7:1 +/- .4 tell me that all's well.

Whats your timing at idle?
 
Its nice to reach that status of "being bored" with your Turbo Regal. Very few have ever ventured into that unknown area before. You know, when the car is running perfect and there is really no mods or money left to dump into it. You have to find something to do with it. Its not naturual to have a GN and not be turning a wrench or waiting for the UPS truck to show up.:D

I am in such a state right now...nothing to do on my car except waste the back tires.:smile:

Wow, that post is dead on. I have recently delivered packages all over the place. UPS is here almost every day!:eek:

Maybe you just need a few more TR's in your life. I have a few so there's always a problem child to attend to. :D
 
It's like I'm reading my own post. Mine look just like that. Including #6 as always being a little darker than the rest. My idle O2's are the same too.

What plug gap do you run??


Somerwhere between .029 to .030
 
What's your cylinder compression readings like? Number 6 a little lower than the rest?

I would flow test the injectors. I don't see how the screwdriver test will tell you anything other than it's working. What kind of injector are they? Pintle, disc?

If the plugs are as old as you say, I wouldn't necessarily blame the darker #6 on your recent idle test. Point being, how did the plugs look before your idle test?
 
How many miles what? On the plugs? Wow, not sure, maybe 5-10K

I'll have to try and see if I can "screw driver stethescope" the injectors and make sure they all sound the same.

#6 is a little darker. Looks a lot darker than it really is in the pic.

I was surprised to see how nice and "white" all the rest were, after sitting at idle for so long.

The plugs look too good IMO. Your car isnt running lean is it? Do you have any pics of the electrodes?
 
I don't really have any close ups of the elecrodes. They're back in the car now. They looked normal to me.
 
What's your cylinder compression readings like? Number 6 a little lower than the rest?

I would flow test the injectors. I don't see how the screwdriver test will tell you anything other than it's working. What kind of injector are they? Pintle, disc?

If the plugs are as old as you say, I wouldn't necessarily blame the darker #6 on your recent idle test. Point being, how did the plugs look before your idle test?


Dont have a comression tetster. Haven't had any issues arise that would prompt me to look internally.

The injectors are MSD 50's
 
Dont have a comression tetster. Haven't had any issues arise that would prompt me to look internally.

The injectors are MSD 50's

I was just interested as to whether or not that cylinder was a little lower than the others. Not that it would be low enough to cause a noticeable problem, since 15% difference from one cylinder to the next can be considered perfectly normal.
A cylinder that is lower than another will generate less heat. Less heat to burn away deposits.

I know that some injector designs can change flow characteristics with relatively low miles on them. That's why I asked what design style the injector was.

I have to mention that if the goal is equal tune between cylinders, you must know the results of a compression test and a leakdown test. You could be down on a cylinder and not realize it using the trusty seat of the pants instrument alone.

Not counting manifold distribution problems, the two variables that are impossible to be sure of without proper testing are injector flow balance and cylinder compression balance.
Ignition timing. From cylinder to cylinder, you can be fairly sure that it won't be too far off as long as all parts involved are in good condition.
A/F mixture. If the ECM is commanding the same pulse width from each injector, then the only variable there is whether the injectors are flow balanced.

Compression, mixture and spark. The three amigos.
 
Back
Top