re. 86 4kq, idle problem (long)
benswann at comcast.net
Tue Jan 6 11:51:56 EST 2004
Does the problem start to happen after a few minutes into the warmup cycle - kind of like someone throwing a switch? Does it happen when engine is just started cold?
I'm alluding to you possibly having a flaky O2 sensor - have seen this many times and it is often exacerbated by moistere - in particular ice and snow at first, until problem becomes a regular poor running issue/progressively worstens. You may try pulling the O2 lead when happening to see if the engine perks up.
[Message-ID: <cf.290b680.2d2b8c9b at aol.com>
Problem started a few days ago. Im gonna explain this the best I can, so
bear with me. Went to go run errands, started car, car ran rough, 200rpm, didnt
stall, but when given a decent amout of gas, car sounded like it was
backfiring (loud "boom" from engine bay). After feathering the gas a bit, the idle
evened out to 1000rpm, and I was on my way. Same thing happened twice later that
day after coming out of a store and getting gas. Later the same day, after
the car sat for a while, I started it up and everything was merry, drove off,
car ran great. Get to friends house, shut down, come back 2 hours later, car
stars awesome, and drives off great. A few mins into the trip, car loses
power, and wants to idle at 200rpm again. Im forced to pull over, and rescure the
idle via my foot, again. If I try and move the car when the idle is that low,
the car of course doesnt wanna go, and lunges forward as the revs drop. Car
gets going, and gets home fine. I had time to look at it tonight, so after a
stuck ebrake, I pull the car into the garage. Check some O2 sensor wiring,
pull the plugs, and check for vac leaks..nothing, everything there checks out.
Fuel filters are a month old, fuel pump wiring is nice and dry, but there is
alot of ice under the car, and around the fuel lines. I did pour in some fuel
injector cleaner tonight as well.
Thats where I stand now. Car does run right when it wants to, and this
problem is sporatic! Any ideas where to start here? Ive asked around alot, but
havnt consulted my Audi tech friend yet...help!
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