lt14 fun

Please help. I have a 97 t/a that is misfiring and I just replaced opti plugs and wires. It all started one day driving down the highway it started stuttering and the ses light started flashing for a minute or so then back to normal ran just fine. This happened a few times until one day it didn't go away. I drove it home and it seemed like it was sucking has real bad. Then the car sat for a few months ( we were in the process of buying a new home). I started it to bring it to the new house and it ran good for about ten min then started missfiring. I put it on a cheap scanner and it said cylinder 4 misfire. I pulled the plug and it was black. I put a new plug in and inspected the wire. Took it for a drive another ten kin or so and missfire cylinder 3. So then I bring it to a shop to have it diagnosed and they said plugs wires cap and rotor. So I put in a whole new opti plugs and wires start it up and a few minutes later ses flashes and says cylinder 3 misfire. Unreal. Another thing it says it system lean bank 1. I do have off road headers and cai but its been that way for a couple years. When I pulled the plus all the pass side were black and dri looked good. Any ideas would be greatly appreciated. It sucks putting $750 into it with no good results. Thanks.

pancho toco loco

iTrader: (8)

What kind of opti did they put in?

lt14 fun

Msd ignition and wires and ngk platinum 4's

xDetroitMetalx

What performance mods have been done to this vehicle? More specifically the exhaust and has been tuned? Have the O2s been checked? Are you still running all 4 or just the front 2?

lt14 fun

Sorry I meant opti not ignition

lt14 fun

I have pacesetters with ory only 2 o2 sensors removed air system and installed egr block off plate. I replaced on o2 sensor last year pass side the driver side was done a couple years ago. Haven't tuned pcm yet that was my next purchase. As soon as I figure this out I will get it tuned.

lt14 fun

I may have figured it out. I got home from work this morning and started it up since it was pitch black out and I could see the tiniest little sparks coming off the spark plug boot and off that little bracket that runs from the header to the black plastic box that the throttle cable runs to. This is a msd OTVC 8.5 super conductor wire kit. Is this common with these wires and what should I do to fix it. I'm going to mess with it when I wake up since the headers were already pretty hot from running it. Thanks

Martin99ACR

please let keep us updated, Im having the exact same problem with my 97 z28, and i also have the same paramaters/variables you mentioned with your car!! Same everything! I need to know what is wrong so the dips can fix my misfiring baby!

moehorsepower

iTrader: (3)

Plugs being black is fuel, this is the reason for the misfiring. You say you removed only 2 of the 02's, back ones I hope. Also, you need to scan and see what the 0's are doing,

lt14 fun

I rerouted the plug wire and the problem seemed to go away. I'm going to take it for a longer drive later ill post back if u have any problems. Thanks again

xDetroitMetalx

If the wires are arcing then that would create a misfire. However, as mentioned above the black plugs are kind of worrying. As mentioned above you did keep the front O2s (I'm assuming yes)? How long has it been untuned from the exhaust mods? That's a lot of changes and component removals for the computer to handle.

lt14 fun

Yes I'm running front o2's and probably have 15000 miles since the exhaust has been done. I know I need a tune and I should be able to get that done within a month

lt14 fun

Ok so I drove it over to a buddies house about ten miles away and it rann great a couple hours later I am cruising home and it started to stumble while cruising at 55 mph. I kicked it down and it cleared up but when I start cruising again it stumbles. Get home and put the code reader on and it says cylinder 4 misfire. I checked the wire and this one looks good. Wtf. It's just Luke before jumping between cylinder 3 and 4. Just a coincidence or is there something that would cause this

lt14 fun

Ok I started pullung plugs today and the passenger side were black again with carbon. I picked up a o2 sensor Do I replace the passenger side then. I assuming so but I believe I changed that one a year or so ago

lt14 fun

I solved the problem. It ended up being the passenger side o2 sensor. Thanks for the replies