Agreed...
Will put the ac delco plugs tomorrow gapped @.060 and then I can determine if I'll need new wires...the Belden wires are cheaper than the Delco's ($87) and cheaper than the MSD's ($92)...will definitely consider buying them if the ones I have are bad...
Do you feel any shaking in your truck at the steering wheel?


Will advise if shaking stops...
Thanks for your support...

 

It's me, AGAIN!
So I gapped the plugs @.060 and bought a new set of wires...the old ones seemed ok...
Damn, I hate taking out the plugs in my 4.3L, I believe cylinder #2 is the the one by the steering wheel? that one is hard...had to use a jack and all...
To keep the story short, it is now missing even more...now I can even feel it accelerating! double checked if all wires were hooked correctly and they are fine...
My engine sticker says the plugs should be gapped @.045, but I don't think that this should create SUCH a miss...it is only .015!!!

HELP!!!!!!!!!!!!!!!!!!!!

 

After hearing that, it sounds like a coil problem. If, when you increase the plug gap, the miss gets worse, it almost always leads to a bad coil. The reason being that the spark is weak enough that it has trouble jumping the gap. This will cause a cold spark of short duration and could quite easily cause the miss.

I just read back through the entire thread (pheww) and noticed that you are running and aftermarket performance coil. First thing I would try is to swap out that coil with either a new one or if you wanted to go real cheap, grab one from a junkyard. It's not the best practice to use junkyard ignition parts, but the price is right. I could get both the ICM and coil from my local pick-n-pull for $3 out the door. I guess it is also possible that something has screwed up in the cam position sensor (in the distributor). I have been hearing about this quite a bit lately, but it has all been conflicting information. I think that the cam position sensor is a hall-effect sensor that works against a reluctor ring (gaps in a ring that get sensed). Some things I have read say that the sensor reads a spinning magnet that is connected to the distributor shaft and that the magnet cracks causing the sensor to pickup an incorrect pulse.

I was tempted to grab a distributor from the junk yard to see exactly how it was assembled and what was inside it just for a frame of reference. I am thinking this is a problem on my Bravada as well. Every so often while driving down the road, I 'feel' a miss, but I get no indication of a miss when I scan it. Definitely weird.

 

The problem is that the truck is shaking like this for about 4 months or so...I changed to an MSD Blaster coil in december and noticed the same results with the stock coil regarding shaking and rough idle...
Do you think that I should buy a new distributor?

I am just about to buy a gallon of gas, pour it on top of the truck and ignite the **** outta of it...[:@][:@][:@][:@][:@]

 

I just noticed that cylinder#2 wire was not hooked up tight...shaking got a tad better but it is now as it was before I changed the plugs @.060 and the new wires...this means that the truck shakes with no matter what plug gap or plug wire I use!!! Just discovered the telephone![:@]

 

Well, that atleast means that your coil/ICM are good... Don't know what else to tell you. You could possibly grab a junkyard distributor and toss it in. The local pick-n-pull here even allows you to get your money back on parts bought there (they brand them when you checkout) if the part is defective. Alls it takes is your time to pull the part. It is very useful for trying out high $$$ parts.

 

I will take the car to a gm shop...EXPENSIVE...if they don't find a cure I WILL sell the car...
This shaking is pulling my %&#%&&^**,,.

 

Hey swartlkk...just noticed the following...
When the truck is cold, the shaking is not felt that much, I believe that it is just engine vibration, but when it starts to warm up it starts to shiver on stop lights...this happens if I have the truck in Drive...does this ring a bell to ya?
I changed the air temp sensor from the intake but this has nothing to do with my issue...after I gapped the new plugs @.060 and put in new wires...the truck feels somewhat smoother and takeoff is slightly better...
Thoughts?

 

What is the function of these parts in the engine?

EVAPORATOR EMISSION CANISTER CONTROL VALVE (what's the difference between this and the EGR? This seems to be for emissions also...Can it be cleaned?)

IDLER PULLEY (can this cause bad idle?)

I am pretty much guessing trying to figure out in any way possible how can I eliminate the shaking at idle on my truck...other than this, it runs like a champ...the other day I beat the &*%$ outta some guy in an Integra who said he'd whoop my ***...sorry for him...

 

EVAP control valve is a solenoid valve that controls the application of vacuum to the fuel tank/charcoal canister. I am not aware of any way to clean it, but it shouldn't cause any problems with your idle quality. If anything, this will cause a higher idle if stuck open. You can check the EVAP system, but if you aren't getting any codes, it isn't the problem.

The idler pulley is a pulley on the front of the motor that is basically just there to support the serpentine belt in its normal routing. This will in NO way affect your idle.

I don't condone street racing and neither does BF.com. Please keep racing on the track.