More ignition problems? (Or not?)

[oes]

So I picked up another used dizzy and got the car idling no problems in my driveway. Little did I know, I was still faced with a problem. Had the car at the dyno ready to be tuned, he was going through all the initial EMS setup crap and once it came time to start putting some load on the motor the problems started. After running for awhile, it would "break up" or "sputter" like you can tell in the video. Car would die sometimes and we let it sit for a few minutes. Started it up again, take it through 5-8 runs all the way to redline and it would start to cut out again after that. Let it sit and repeat.

Possibly be the dizzy? Grounds? Coil?

http://www.fatboyrunning.org/stupidcar.zip

If you need any more info, let me know

For ****s and giggles. Since my boost controller wasnt working, it was tuned at wastegate spring psi (8-9ish?)

[USMCgetsome]

MAF!

[S13FX]

To me it sounds like your not firing on all four cyl's. Or maybe you skipped a tooth on the dizzy. Did you check your timing. I would hope so after dizzy replacement.

[WDRacing]

Yep, you're missing a cylinder. Get it running, then pull the wires one by one. The that doesn't effect anything is the culprit.

[oes]

Running MAP

Timing was set to base after we replaced the dizzy.

Would the problem only occur sometimes if its missing a cylinder?

[S13FX]

Has your car always sounded like the way it does in that vid?

[TheOne]

yep, yer missing a cylinder, tho it doesn't sound like ignition, check it like WD said, also check injectors the same way.(pull wire while engine idling, idle should go eratic, if idle still the same then its that plug/injector)

at least my car sounded the same, cause my injector #4 either wasn't firing at all or was firing too much fuel(thus causing it to flood that 1 piston, i believe thats also why my engine spun a bearing, fuel prolly went down the pistons and into the bearings, my oil was black even after a less than 500 mile oil change, but replacing the injector worked....till rod knock got worse)

kinda sounds like a wrx, at least mine did cause of that and i had an exhaust leak after the cat.
Modified by TheOne at 11:24 PM 4/23/2007

[oes]

I just got the car together about 2 months ago, and this is the most run time its had. Its a built motor running AEM EMS.

I will check the the wires after work today. I am assuming to try it while its acting up right? Not running normal?

[oes]

Video of the car after sitting for awhile:

http://www.fatboyrunning.org/goodcar.zip

Sorry its so big in file size, i suck at compression and most video stuff period

[oes]

Ok, I pulled the plugs one at a time while it was acting normal, idle changed as expected on each one. Then I did it once it started acting up and I couldnt really tell a difference. It died a couple times after I pulled wires off.

[WDRacing]

Have you inspected the wires closely? I had one get worn and it on had issues when I was on boost. At idle it was normal.

[oes]

Yea brand new, we also changed plugs out half way through the tune session. Reading up on some issues with AEM EMS and stock CAS on Nissans right now. Seems like similar symptoms

[oes]

I tried what was suggested with the EMS (changing MX Sync Test to 8 instead of 9). It fired up fine at first, then i started to back it out of the driveway, down a hill, and it died and wouldnt fire back up. I changed the setting back to 9 and let it sit for a few minutes and it fired up and started suttering like my video.

I pulled each plug wire at a time while it was doing it, it died each time i pulled a plug.

I still need to check timing, but it hasnt been touched since last time i installed the distributor and it was set to base timing.

In other news, when i first started it up today, I took it out for a drive. Got it through 1st, 2nd, and 3rd gear and drove it back to my driveway real quick before it started acting up. Didn't start acting up till a bit later though.
Modified by oes at 5:14 PM 4/25/2007

[gaehrings13]

Check the firing order.....

[TheOne]

did you check both spark plugs and injectors? as i said before, 1 of my injectors(#4) was causing the car to run like whats in your video, it would run fine sometimes but most of the time it'd run like if it was on 3 cylinders.

[lrb_2000]

same here.. one of my injectors would cut out when I tried reving sometimes, others it would be fine.. but it sounded just like that when it happend. I zapped it with a 9v battery a few times and it's worked fine ever since lol.

[oes]

I've pulled the plug wires one by one and it died each time. I will try disconnecting the injectors one by one next and see what happens. I had to stop messing with it yesterday because one of my plug wires left the boot around the spark plug after i pulled it out. :\

[DammitBobby]

Are you running internal or external coil? I had a simular problem on a camry. It would run fine for a short period of time but after it heated up the coil resistance would go way high. The coil was located in the distributor and you couldn`t see that it was cracked and leaking. You can get a coil cheap. The other thing you want to try is a fuel pressure gauge. Cheap gauge and adapter for around 30 bucks. Well worth the money when trying to troubleshoot EFI. Good luck.

[S13FX]

I either think it's your injector or you distributor is flipped by 180*. I would check your timing since it's the easiest to do before trying anything crazy. Then check your injectors.

[oes]

This is on a built ka24de-t, running aem ems, ive got a fuellab fuel pressure regulator with a gauge attached.

The coil I am using is the stock coil that came with the car. Also using a used distributor, manufactured by mitsubisihi

Will double check the timing this weekend when i have access to a light

[oes]

Update?

The other day, was driving it and it started cutting out again. Pulled over and popped the hood. Grabbed the dizzy itself and BURNED my hand. It was fine on the side away from the turbo/mani but right there on #4 plug wire it was extremely hot. Let it cool for a min and it runs again fine. Figured the heat was causing the misfire on #4. Now i have to figure out a good way to keep it cool. Any suggestions? Sound likely?

This is to give an idea of how my setup is

[s14_240sx]

Use heatshielding to shield the dizzy from the heat (smart eh?). If it still runs like poo replace the dizzy. The heat could have permanatly damaged it? I can't remember off the top of my head but cylinder 4 is the dizzy plug closest to the exhaust manifold right?