SkiBumDreams

so i just finished replacing water pump and opti tonight. i took it out and when starting from a stop or getting into the pedal just a little it will pop once or twice and hesitate for a moment. i am thinking it coul dbe plugs and/or wires? The week before i redid the intake gasket. is it possible for an intake leak to cause a backfirelike this? what do you think?

seawolf06

Does it do it at idle at all? I don't think an intake leak would cause backfiring, if anything it would run rough because of vacuum leak or just spit oil out.

More than likely crossed or arcing wires.

Voridaeus

As suggested make sure there are no wires crossed, and no arcing (check at night).

A lot of people have gotten bad optis brand new. I don't want to tell you to rip it off just yet, but in all seriousness it's pretty hit or miss with these freakin' things. I'm still running on my stock unit at 55k miles, but I'm dreading the day that I have to do my opti... hope I never do.

As far as intake leak, unmetered air will give you a severe loss of low end grunt and cause rough idle issues. No backfires though.

That said, may I ask why you changed the opti? Did it die too when your pump pissed all over it?

SkiBumDreams

changed opti because it had a crack in it probably cause when i changed it only a couple months ago i torqued it down to much. Thats an expensive mistake!! it doesnt really back fire at idle just sometimes when accelrating from a stop or acclerating a little harder than normal at low speeds. there are no noticable oil leaks from the intake (since i replaced the gaskets) but i do have one from passenger valve cover and thats why i think it may have fouled a plug or damaged a wire, or am i completely off base on that assumption? i know the wires are not crossed i double checked that, and i have never had backfiring even a slight one from the two other times the optis have taken a dump on me.

SkiBumDreams

also the backfire had been happening before i did the the last opti change. this is why i dont really think it is the opti. I am starting to think there may be a heat sensitive issue as well because it seems to run fine maybe a little miss but no backfire until it gets warmed up. its not a real loud backfire just some "pops".

the icm and coil were changed last fall, so they are not very old but did get a little sprayed by oil from the intake leak. i also replaced pig tails on my map sensor and both plugs going into the coil. they were soldered well and the wires are matched properly. i am planning to change plugs and wires tonight should i pick up a new coil too? is it worthwhile to upgrade the coil to an msd blaster coil?

97greenie

I just did plugs and wires a couple of weeks ago and it was fine for a couple of days and then I developed those exact same symptoms.If I am driving at 50 or above and hit the throttle a little bit I get a misfire.If I stand on it,it doesn't miss,and it only happens when the car is warm.I popped the hood and found my #7 wire was touching the manifold with the conduit I put on it melted to the wire.I'm going to assume that is why I have a misfire and you should probably check your wires out.By the way...how could I be so stupid?