Hey guys, so I need some help please. I'm going to try and explain everything is as much detail as possible. If you have any questions, please ask and I will explain more clearly if need be.

On Saturday morning I did a boost leak test and changed my plugs and she was running very smooth. I took her out for a drive and while I was driving I felt a jerk, kind of like I ran over a bump. I didn't think anything of it until it happened a few more times so I pulled over and check for any loose lines or anything and everything looked good. The car just felt kind of rough though. So I started her up again and everything was good, it idled fine. I was driving home and all of a sudden it jerked again and died, luckily right in front of a gas station. I tried to start it again and it would just crank. So I got it towed home. For some reason I thought it was my upstream 02 sensor (when it went out last time it has the same symptoms kinda). I changed that out and I let it idle for a while, everything seemed good so I took it for a drive. After about 10 min it started to do the same jerking and start really varying the AFRs. It died again and I pushed her home a block. When I got I home, I started her up and she idled normal for about 15 minutes. I then took her down the block and it did the same thing again and died. So I let it sit for a few hours and took a viedo of me starting her. I am keeping it alive with the throttle but it will idle at around 500 and sputter then die.

I really have no idea where to start or what could be causing it. Someone said to check my MAP sensor and everything seemed fine there, wasn't dirty or anything. I read a lot of threads but nothing seemed similar to what I'm experiencing. Here's the link to the video of me starting it. Thank you guys in advance!!

 

what did you gap the plugs to?

 

.025 and I used ngk br7es. It's what my tuner told me to gap them to and to use those plugs

 

that gap should be good. I usually use bpr's but i dont know if that would be causing your problems. Is your car throwing any codes? It can store codes without giving off a CEL.

 

My bad, I forgot to say that. No cel light and nothing stored when I scanned it

 

check all the vacuum hoses and/or do a boost leak test and see if anything might have slipped off.

Edit: i just noticed you already did this. What do your LTFT mid and LTFT low look like (logging options in evoscan).

 

Ima be honest man, I have no idea what those two thing are. I've also never used evoscan

 

EGR valve? bad MAF? TPS go whack?

 

I'm just running an Omni 4bar MAP sensor, and i took that out and inspected it, it looked in good condition and I wiped the inside to see if it was dirty and it was spotless so I think it's good? Not sure how to exactly test it besides swapping one that I know works. And for the egr valve, I was reading some other posts and when I went to look for it, and I could not find it, so maybe the previous owner deleted it? And wouldn't t throw a code for a tps? When I've had it going wrong before it threw a code, but I could always test it just to be safe

 

fuel pressure regulator maybe? it almost looks like fuel flooding seeing it goes all the way to 9.8ish afr right before it cuts out, that why i suggested egr as i believe i causes these symptoms as well.

is this where you looked for it?
https://www.evolutionm.net/forums/ev...-canister.html

can u see a block off plate like this on the STM plate on bottom of pic?
http://www.curtbrownracing.com/images/001_(2).JPG?994

 

or... a gigantic vac/boost leak.

 

Okay, I see what you're talking about, I'll have to take a closer look when I get home to see if I see the plate. This might sound stupid, but I don't have to remove the intake manifold to see that, doesn't look like I have to see it.

 

maybe your coil packs are going out.

 

I had a spark tech non cdi on there. And when I got my retune (I moved from so cal to Chicago), my tuner said to get rid of the sparktech and he put on stock coils. So they were good as of 5000 miles ago. But I'll look up how to test them and see what's up. I could also try throwing my sparktech back on and see what happened

 

yes i would agree with a boost leak as well, my friends car with a boost leak sounded exactly the same pulling up into my garage. regardless. keep us posted please.