Sgt.Stinkfist

iTrader: (6)

I finally pulled my 79 out and have been driven it for bout 3-4 days now.i changed my fuel filter yesterday and put some new NGK's in today and it was running fine w/ a 800 rpm idle...but following an oil change the car would idle at ~1500 rpm and was missing sparatically, i drove it around the block, it felt like it had more power than before but would pop between shifts and it stalled out at a stop(w/ no load).i pulled the plugs and they are black (they have 10 miles on'em!).could there be a link between the oil change and the over rich condition or is it more likely a carb problem rearing its ugly head and the timing is a coincidence?

Bass

Do you have spark for both leading and trailing?

Sgt.Stinkfist

iTrader: (6)

do i check spark by grounding the plug to the engine and cranking?if so then i'll check that tomorrow.

Bass

yup, just make sure that you pull the fuse for the fuel pump so you don't flood the engine. If you have a timing light than you could just check with that while the engine is running. But either way is fine. Let me know what you find.

BMS2004

yes it is a coincidence really theres, nothing that would make it idle higher and stall out, and make it run rich. Were the plugs oil coated or just sooty like from running rich?

Sgt.Stinkfist

iTrader: (6)

plugs were very sooty, no oil or moisture was noticable

BMS2004

hey get on AIM

Rx-7Doctor

iTrader: (13)

Retrace your steps, usually when there is an issue after you just performed work
that something was disturbed. Recheck all your ignition wires for proper routing especially the coil wires. Inspect for a broken or disconnected vacuum hose. rx7doctor

cpa7man

iTrader: (2)

Yes, what the doctor said.

BMS2004

yea, but he said he changed the plugs and it ran fine until he changed the oil meaning that the wires should've been A-ok. On the other hand regardless of what he did, the idle shouldn't just shoot up after changing the oil.

Sgt.Stinkfist

iTrader: (6)

thats why im so confused, i drove around for an hour and got gas,changed oil and on start up it ran like ***, idling high and missing

Rotor13B

Try giving the carb a good tap on the side, Maybe you have sticking floats.

Sgt.Stinkfist

iTrader: (6)

thx for the advise, ill give it a try

Kentetsu

Like the good Doctor said, look for something that might have been disturbed. Go through the same motions, replay the entire event while thinking about the issue....

Last time I changed my oil, the cables for the throttle and choke were kind of in the way. I moved them over a little and propped them behind some convenient item so they would stay there while I put the oil in. When I started it up afterwards it was running rich because of the added tension on the choke cable, which was causing the choke to close a little bit. You might want to check that out.....

Good luck man.