Alright guys, I have been suffering from what I thought was just fouled plugs giving me a misfire. I swapped out my BPR7ES yesterday for BR7ES gapped to .26. Last night I did a log and didnt get what usually feels like bad misfires throughout the rpm range. What I am noticing is that my load is kind of all over the place which leads me to believe I am getting a boost leak.
I havent done a boost leak test yet but I just wanted some opinions from you guys before I do one and then take a hard look at the ignition system.

By the way I am only running around 19-20psi peak.

 

I dont think your load looks abnormal. What were your previous plugs gapped at and what did the plugs you took out look like? My old Dynoflash tune ran pretty rich. It's kind of hard to see the problem without wb readings. I've seen a few tunes knock a little when coming into boost and it's normally not a big problem. You might try pulling a little timing to see if it goes away. Could just be the limits of the fuel / weather / timing.

Since you dont have knock in the higher rpm ranges it is likely to be boost related misfires. You could try closing the gap a little more on your plugs, my car is pretty sensitive to plug gap.

When are you feeling the misfires? Are you actually just feeling the knock that is being logged?

 

Thanks for taking a look

 

well no problem, when I was having spark related misfire.. it was popping when I would go WOT, right at the boost spike. Until I changed plugs I just turned the boost down and it went away. Knock feels a little different, I cant always hear it but I can feel when timing is being pulled.

 

I am basically having the same misfire problem as you did. What did you end up gapping your plugs to? .22? When I get back from Florida I will have to change the plug gap. I definitely need to get rid of the crappy Magnecores too. I wonder if Autozone replacements would be better.................................

 

A boost leak would show an unusual increase in airflow hz with respect to IPW or load when compared to when you feel your car wasn't leaking. Airflow #'s look normal to me if your using HKSrs intake.

Hate to say it but the only way to tell is to get your hands dirty and pressurize the system to about 15psi and it should hold

Severe missfire I think gives a code 0300 but a WB can detect slight miss

 

Just curious, what type of tool did you gap plugs with?

0.026" should be good to 23psi with healthy ignition

 

i run them around .22 unless using an ignition... i use a digital caliper or feeler gauges, and tap them gently

cb

 

I just use a feeler gauge. Im using the Buschur intake system......so about the same airflow numbers as the HKS.

 

your timing curve and knock look fine....the car looks healthy in the log, but you're saying you have a misfire, where in the range are you seeing misfire?

 

a misfire would likely only show up as a rich area with a wideband. At least that's what my logs looked like when the plugs were old and the spark was being blown out by the boost.

 

just going to have to do a boost leak test..

 

I would encourage people to do boost leak tests even when you dont think you have a leak, periodically throughout the year. You'll be suprised to find a few every time.

 

That log is right after I changed the plugs and on a wramer day so there wasnt a misfire at all. I have some older logs when it was colder when I would get the misfires, if you want to see them.

 

How can you see misfire from a evoscan log?

There are only three ways to spot miss I know:
1) WB sharp lean spikes
2) Sometimes Code 0300 (random misfire)will be right
3) Oscilloscope (dont ask how?)
4) If miss is bad enough the car would pause for brief periods on accel