still running rough
Thread Starter
Instructor
Joined: May 2004
Posts: 183
Likes: 0
From: BINGHAMTON NEW YORK
still running rough
i just got done doing a tune up on my 96 vette its a LT1. i did plugwires and plugs fuel filter but didnt do the opti. well my check engin light is still on i reset it with a scan tool and a few mins later it comes back its telling me a missfire in #7. now this my seem stupid but should i replace the opti?or is it a diffrent problem ?thay are a lot of cash and I didnt want to do it unless it has to be done.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
I would check the plug wire connection and make sure the plug is the correct gap. A misfire could be due to a bad injector. You can ohm the injectors especially #7 and see what numbers you get. Don't blame the opti yet until you check other little things.
Le Mans Master
Joined: Jan 2006
Posts: 6,564
Likes: 6
From: Woodstock Georgia
That is not very likely to be an opti problem, not at all in fact. Bad plug, plug wire, or plug wire connection IS likely. Start it up at night in darkest place you can, raise the hood and look for any sparking from a shorted plug wire is one quick/easy check. It won't show every possibility, but too easy not to do.
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
I posted you a reply on C4 Nation... But here it is again..... 
Originally Posted by CasetheCorvetteman
Start with ignition control module first (checking), check for leaking/fouled injector, check the O2 sensors, check the EGR, and check any wiring to any of these. THEN if all if perfectly fine there, and no one else comes along with anything else to check, start thinking about the distributor!!(it doesnt sound like something cause from that to me)
Le Mans Master
Joined: Mar 2004
Posts: 8,700
Likes: 298
From: Ft. Lauderdale Fl
Use the old wire test. When its dark, lift hood, start engine and look for spark gaps. They will light up things. It may not be a bad wire but just touching a ground--reposition/move the wire and presto, you fixed it. Use a zip tie to reposition plug wire.
Race Director
Joined: Jun 2004
Posts: 13,957
Likes: 706
From: WI
It didn't have a miss before the tune up right? Trace each wire and make sure they are correct. You can unplug each injector to, the one that unplugs and does not change the idle, would be the one that is not firing(miss). Spray the wires with a mist of water and check them in the dark for arcing.
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Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Originally Posted by C4EMT
i also just rememberd that when i rev it up it puts out some black smoke from the left tail pipe and the car has 105.000
(I now have some brand new offsets that are even better for this job
)
Last edited by Casethecorvetteman; Aug 3, 2006 at 12:11 PM.
Le Mans Master
Joined: May 2005
Posts: 7,348
Likes: 2,272
From: Central Maryland
Check for a leaky/stuck injector, bad spark plug, or bad plug wire (or bad connection between wire and Opti or wire and spark plug) on #7.
It's not impossible that the Opti is causing your fault, but I seriously doubt it. My bet's on a leaky/stuck injector, based upon your symptoms, and that's what I'd look for first.
Be well,
SJW
It's not impossible that the Opti is causing your fault, but I seriously doubt it. My bet's on a leaky/stuck injector, based upon your symptoms, and that's what I'd look for first.
Be well,
SJW
Le Mans Master
Joined: Jan 2006
Posts: 6,564
Likes: 6
From: Woodstock Georgia
Originally Posted by C4EMT
Thanks guys
it ran verry good untill one of my plugwires fell apart at the plug boot and was held on by one strand of wire
ill give it all a try and see what happens
it ran verry good untill one of my plugwires fell apart at the plug boot and was held on by one strand of wire
ill give it all a try and see what happens
Thread Starter
Instructor
Joined: May 2004
Posts: 183
Likes: 0
From: BINGHAMTON NEW YORK
Originally Posted by aminnich
Sounds like problem found and soon to be fixed.
lol thats what started the problem and why i did the tune up. this is a new and after problem. but could be linked to problem #1
Le Mans Master
Joined: Jan 2006
Posts: 6,564
Likes: 6
From: Woodstock Georgia
Originally Posted by C4EMT
lol thats what started the problem and why i did the tune up. this is a new and after problem. but could be linked to problem #1
Oops, a premature celebration. :o
