NEED ADVICE

[jimmyj333]

I am trying to diagnose what appears to be a mis-fire.
Maggie, lt's, cam
I have NGK TR6 plugs, and MSD wires
Need to know if .040 would be the gap I need
Also the first wire I checked is coming in at 28.4 ohms res. and plug is coming in at 40k ohms.
any help would be appr. thanx.
Also what else to check?

[victoryred1ss]

I would put the stock plugs and wires back on and see if your miss goes away.. since you have LTs it would only take about a half hour, plus the stock igniton system is fine anyway..btw you do have a custom tune with that cam right?

[jimmyj333]

Ya I got every thing tuned in.
So far bank 1 plugs and wires are looking good. Resistance values are all equally in the ball park.
Now bank 2 it's gonna be a biatch!!

[jimmyj333]

All plugs and wires spec out the same. No cracked insulators, electrodes look good, gap's all at .040, all boots seated. Didn't see any spark scatter in the dark. Checked for vacuum leaks. Idle still drops off 100-150 rpm randomley.
The quest goes on.

[sspaul]

clean the fuel system out, i had to do this on my 01 silverado, i used seafoam and used it like the said. you spray in vaccum hose, you put it gas tank, you put it in the oil. the only reason i'm suggesting this b/c my truck was doing the same thing, and it had trash in the injectors.

[quick89]

sounds like issues with the tune
do you have a shop local that can take a look at the tune?
check engine light?

[wbt]

For spark plug gap, you will only notice a miss up in the RPM range if you are blowing the spark out with too large of a gap.

Appears your issues are around idle. Any other symptoms like a high RPM miss?

If it is not missing at high RPM then your gap is fine, fuel is fine, and most likely your plug temp range is fine.

Idle misses are caused by:

1. Tune
2. Vacuum leak
3. Bent valve or mis-adjusted rockers not allowing the valve to seat properly.

Is the car hard to start after being driven for a period of time?

[jimmyj333]

Originally Posted by wbt

For spark plug gap, you will only notice a miss up in the RPM range if you are blowing the spark out with too large of a gap.

Appears your issues are around idle. Any other symptoms like a high RPM miss?

If it is not missing at high RPM then your gap is fine, fuel is fine, and most likely your plug temp range is fine.

Idle misses are caused by:

1. Tune
2. Vacuum leak
3. Bent valve or mis-adjusted rockers not allowing the valve to seat properly.

Is the car hard to start after being driven for a period of time?

Trouble only at idle. tune is spot on, checked for vacuum leaks. no hard starts hot or cold.

It could make sense that it might be mis-adjusted rocker, and hopefully not bent valve, because valvetrain and cam were changed out and never idled right after work was done.

[tony1]

If you do a search on rough idle this you'll find that its common to idle like that (there are countless threads on this) .. it will jump time to time 100rpm or so. it's normal.

[jimmyj333]

Originally Posted by sspaul

clean the fuel system out, i had to do this on my 01 silverado, i used seafoam and used it like the said. you spray in vaccum hose, you put it gas tank, you put it in the oil. the only reason i'm suggesting this b/c my truck was doing the same thing, and it had trash in the injectors.

Ding Ding Ding:

SSpaul is the winner!!!

I ran sea foam thru the gas tank, and so far 3 weeks later the eratic idle problem is gone.

Yes it still fluctuates a little on idle, but before it would drop 200 rpm.

Now I need to put together the formula for 600-600 plus, but first I need to explain to Cherry hills villiage Colorado the 60 in 35 zone.

sunsabtchs r gunna hang me

[sspaul]

glad it was nothing major man. now about the speeding ticket try this it worked for me a while back, go talk to the assistant da and tell them you want to pay the fine but don't want the ticket on your record. i did this a few weeks ago and they dropped it from a 25 over to a nonmoving violation, still cost me the fine of the speeding ticket tho.

[PQ]

Originally Posted by jimmyj333

Ding Ding Ding:

SSpaul is the winner!!!

I ran sea foam thru the gas tank, and so far 3 weeks later the eratic idle problem is gone.

Yes it still fluctuates a little on idle, but before it would drop 200 rpm.

Now I need to put together the formula for 600-600 plus, but first I need to explain to Cherry hills villiage Colorado the 60 in 35 zone.

sunsabtchs r gunna hang me

I'll have to try this.

[Slowhawk]

The rolling idle on a stock car is pretty normal. It has to do with the idle spark table mixing with the Main spark table. Smoothing those 2 together helps alot.