intermittent missing...wtf?

old skool

New Member
Apr 17, 2009
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Milwaukee
Back again with another problem!

the other day i was driving home and the car started missing out of no where. I started her up the next day, ran smooth and then started missing again after a few minutes of driving. I parked her again and checked for bad plug/injector wire connections, everything was fine. the next day she fired right up again, smooth as can be, so i went to sonic (about 10 - 15 min away) and everthing was gravy until i pulled in the lot. She started missing again so i revved a lil and backfired pretty decently. I stumbled into my spot and i shut the car off until i got my food. when i fired her back up, everything was fine by the time i got home. THEN i needed to go to work a couple hours later, fired her up and the idle was rough like it was missing again...now today i fired her up after sitting all nite and she's smooth as a baby's bottom again. WTF?!?!
(side note: had my tech on a test drive a while ago and said i was blowing out my spark, even before i put the 550s in. he could tell by a fast paced clicking behind the glove box around 4000 rpm. That's when i did my plugs and wires and the problem persisted)

Just the facts:
-Changed plugs 2 weeks ago (autolite 5503 @ .030 gap)
-RC 550/LEX combo
-Hard pipe intake w/ cone filter
-FP @ ~30 vac on
-HKS down pipe & 3" exhaust w/ test pipe
-WBo2
-AVC-R
...all the numbers are pretty good, def a bit rich tho. AFRs dip to the low 9s (iv'e seen high 8s) under WOT (still stumbles a bit under heavier throttle in 3rd gear and up in higher rpms), cruises around mid to high 14s and idles in high 14s. Between shifts under normal accel. AFRs dip anywhere from mid 11s to mid-high 12s

hope that long-winded info is useful to you guys, i'm fuckin boggled. :1zhelp:
Thanks!
 

rayall01

New Member
Oct 10, 2008
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Westfield, ma
Right after I finished my rebuild I developed a missing problem at idle. Turns out to be coil related. I just replace my whole coil pack with another I had around, and problem solved. The engine had no spark issues, when I blew my head gasket, but sitting around for seven months, I guess something got tired. Try checking for spark first.
 

old skool

New Member
Apr 17, 2009
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Milwaukee
UPDATE: just took her out for a spin. She was running fine, no missfire or stumble until WOT in second when i hit 4400 or so RPM and it "hit a wall". After that i let off, came to a stop sign and now she's missing again...
 
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old skool

New Member
Apr 17, 2009
92
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Milwaukee
dumbo;1335058 said:
Have you checked for codes? And you spark plug gap seems like a little much.

no codes...i was gonna mention that in my opener, forgot about that.
what size gap are you running? i've been told that .030 - .031 is pretty much standard
 

djazem1

New Member
Nov 12, 2007
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philly
does it seem like it only does it when the car warms up? i had pretty much the same problem...if i drove it easy and not rev it to much it would last longer before missing....i found out it was my fuses by the pedals were all corroded, check that out!

Azem
 

old skool

New Member
Apr 17, 2009
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Milwaukee
not losing any coolant other than a small leak from one of the hoses i need to replace. it does have a metal HG that was put in no too long before i bought it, so i doubt its a BHG unless the torque is off...i doest it warm and cold sometimes. i'll definately check to see if i have any corroded fuses and also check for bad grounds while i'm at it...damn this is irritating. it would be a sweet ass car if it wasn't for these finicky little issues.
 

djazem1

New Member
Nov 12, 2007
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philly
haha i know how you feel my car was down a month because of those fuses haha i kept thinking it was something bigger than it was.... good luck fixing it

Azem
 

dumbo

Supramania Contributor
Jul 16, 2008
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Albera, Too Far North
old skool;1335061 said:
no codes...i was gonna mention that in my opener, forgot about that.
what size gap are you running? i've been told that .030 - .031 is pretty much standard

Sorry .031 is the norm. I think I put mine to .027-.028 but I doubt that is causing your problem.
 

old skool

New Member
Apr 17, 2009
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0
Milwaukee
it's all good maing. i'm just about to head out to check it out again...thanks for the suggestions guys! hopefully today i can find out what's going on..i'm feeling pretty good about it.

UPDATE: froblem solved (crossing my fingers). It was a bad ground wire...nothing a little di-electric grease and a tiny screwdriver couldnt fix. i hate electrical shit. thanks again guys!
 
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old skool

New Member
Apr 17, 2009
92
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Milwaukee
injector 4. it wasn't backed out enough to completely sever the connection, but it got loose with vibrations. i used the stock wires and RC clips when i did the injectors cuz i didnt want to cut up the stock harness incase of whatever...so when i retrofitted the new clips on i had an issue getting the wires thru on #4. i took it apart again and made sure the tabs on the connectors were locked in place and secure more-so than last time. everything regarding #4 has been giving me crap for the past couple weeks, so i hope that's the last time i'm gonna have to make corrections to it