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Spark plug issue???

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I thought maybe I was getting a leak through my EGR valve, so I deleted it last night. The car ran terrible on the way to work. I was shocked to disover how much the EGR affects the AFR.

I have replaced plugs and coil, thoroughly checked for vaccum leaks, checked timing, checked compression, reloaded the software on my fuel injection computer...

In short I am totally stumped.

I am wondering if it could be a valve issue. I have been having problems with my valves, but, becuase all cylinders make pretty good compression (140-150 on a crappy Harbor Freight gauge) and because occasionally the vaccum signal will stabalize, this seems unlikely. Could it be that one valve is just barely sticking enough that it is closing late?
 
Morris:

Didn't you have a sticky valve problem before?
Lube the valve guides with kerosene (or Marvel Mystry Oil...same thing) and see if it improves temporarily.

Rob: I just have a stock Pertronix ingition. It fits in where the points/condensor used to be. No external parts...real simple. Instead of their Pertronix coil (or a Lucas Sport Coil), I put in a coil and ballast resisitor "for a '65 Chevy V8" (that's what I asked for at AutoZone). The spark is almost welder-level and has been reliable for 4 years with nothing done.
I use old style solid copper core wires (from Harley parts place) and old-style side-wire distributor cap (looks more "period")
One thing: most folks would set it up for a "bypass" of the ballast resistor for starting. I didn't bother and it seems to start fine going through the ballast resistor all the time, even when cranking.
 
Fuel injection computer, hay wait a min. Morris, what is this a rocket ship?

At this point I would suspect the dizzy cap or wires or something in that general area anyway.
 
Do you think it could be a bent push rod?

Maybe when I was having those valve sticking problems, one of my push rods got abused?

Jack, I have visually inspected my ignition stuff quite thoroughly. I have misted everything with water last night, and saw no errant sparks. My dizzy mechanical advance springs seem pretty week, but other than that, everything seems fine. Is there anything I am missing? Are there any other "checks" you can reccomend?
 
Plugs is all that is left, think I might replace one at a time. Otherwise, beats me. Yea I know the color was good, hmmm.

Kinda comes back to an air leak some place dosn't it.
 
Maybe the vacuum guage is telling you something. I would look real close at it and check it against the diagnostic sheet.
 
Try setting the timing at a higher RPM.
I set mine at 30 degrees at around 5000 RPM (it's a pain, but then you know your getting proper advance at the top end). All you have to do is mark where 30 degrees BTDC is on the front pully.
The pushrods are worth looking at too.
Headgasket may be the problem too.
 
Gug! I adjusted valves and replaced two push rods last night... still running crappy as ever.

For about 5 minutes on the drive home yesterday, it performed flawlessly. I wanted to cry.

I am too scared to set the timing at 5000 rpm, Nial. I don't even rev it that high when I drive it.
 
[ QUOTE ]
I am too scared to set the timing at 5000 rpm, Nial. I don't even rev it that high when I drive it.

[/ QUOTE ]

You may not need to go that high. If you have a stock dizzy, not necessarily for your car, but a stock BMC/BL curve, you should be able to look up in the shop book the rpm where max advance happens. It's probably somewhere between 3500 and 4000 rpm.

Alternately, get your timing light out and rev the engine until the strobe stops advancing, and note the engine speed. That's where you're max advance is, and then you can set that to 30 degrees, or what you choose.

Hope this helps.
 
Sounds like something might be sticking?? Dizzy or carb?
 
Here is another theory:

The mechanical advance springs on the dizzy are weak. Perhaps they are so weak that the advance is "bouncing."

I downloaded the trouble shooting guide for Lumenition, and I will run some tests on that this weekend.
 
Okay... tested the spark this morning and it is EXTRAORDINARILY weak.

Could this be the source of all my woes?

I mean, I am going to fix it anyway, but it sure would be nice if it clears up this frustrating problem I am having.
 
Oh weak sparking, miss fireing and poor running.

You got it I am sure. Good on ya.

Hay for next time check the easy things first. Like does it get fire and fuel. Hehe.
 
The question I have now is: am I justified in buying a Mallory multi-spark controller. Wife says NO! but I think she may be wrong on this one.
 
We have a good coil and condencer? All the connections are good, the roter and cap are like new, the coil wire is OK?

Spark should be hot. If not something is wrong going back to the input side of the coil. 12v in right? gota go someplace.
 
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