There is no way the coil is bad. It would not miss at low rpms and then clear up at high loads. Which, put a much larger demand on the ignition system.

I would do a power balance test or just go the old trusly compression test. Just to make sure you don't have a lower cylinder. Sounds like to me, you could have a burnt valve... just guessing though.

 

Try doing a vacuum test! This`ll tell you if anything is f`d up internally....if the vacuum guage goes all over the place, I`d suspect a valve or a valve spring. Good luck.

 

the first mechanic who had it, hooked it up to the smoke machine to try to see if there were any vacuum leaks, he said that it was ok.

 

Nah I don`t mean a leak test. I mean how much vaccum the engine is actually drawing. Hook up a vacuum guage to a vacuum line going to the intake manifold. If you have a broken valves spring, and the valve isn`t opening all the way or not at all, or even a rocker arm, it can`t draw much vacuum. This is text book stuff ask your mechanic to check it out...should take all of 5 seconds. If you want to do this your self, contact me and I`ll help you out as I have a chart that tells you what the different vacuum pressures mean. You can learn alot,even head gaskett problems and it`s a hell of alot easier then ripping the valve cover or head off.

 

I would take your car to the dealer.They have machines that cost about $25,000 that they can hook up to your car,and tell you exactly what the problem is.Hope this helps.

 

if your car came to me I would start with (depending on how it ran) a vacuum guage and check engine vaccuum at idle.
check for codes (I know you said no codes found but I would check again) than other readings such as O2 readings and fuel trims.
next would be to hook the vehicle to a ignition analyzer and take a look at the spark patterns, many ignition related and internal engine combustion problems can be found by looking at the spark patterns on a analyzer.
if still nothing after that, than things would get a little more dificult.
oh and check the EGR valve.

your problem sounds like a easy one realy.

what cly injector did the first mechanic replace and why?

 

on N/A engines spark voltage requirements are actualy higher at lower RPMs such as below 3000rpm, because the advance curve of the igntion system. say.. at 1,500rpm there is 10deg of spark advance.... that means the spark needs to fire with the pistion closer to the head in a higher pressure inviroment.... higher voltage requirement than fireing 35 BTDC at redline.
on boosted engines this theory goes out the window because at higher RPMs on a turbo or SC engine usualy has higher cly pressures because of boost presure

 

Maybe I missed it, but did you ever say if there were any SES codes? If so, what are they? Also something to check...I noticed that cars with stock type plugs and modifications that move more air like headers, catback and CAI sometimes foul plugs. My '94 had this problem also...would load up near idle but clear up as it revs. I dont understand it, but anyways, not a bad idea to check your plugs for wetness and fouling. Make sure none of your plug wires are burning through anywhere or crossed as well. But first and foremost make sure the engine doesn't have anything obvious like bad O2 sensors, stuck EGR valve, etc...

 

yea im pretty sure mine has the same prob.....say im crusing in 2nd gear at 1500 and keep it there @ 1500, the motor has this reoccuring miss which has a rhythm. it makes the car shake more when it does this... NO lights...so im guessing opti. but after crusing @ 1500 and go to push the throttle down more, the motor feels like it bogs......car has new fuel filter, plugs, Taylor wires,pcv valve. Motor has 122,000 and i think its a stock opti !!!.

so you can just clean out the EGR valve maybe that will help.
how do you check for bad 02 sensors?. (car is not throwing a SES light)

Thanks!

 

been there, done that...first mechanic was at a dealership

 

NO codes,BRAND NEW wires and plugs!

 

You have an OBD1 so it won't send a code as like the odb2 will. All of my problems went away with the new Opti but I still get alot of black smoke at wot and a very small "backfire" every now and then. I'm sure your problem will be a simple one. At least you have a new opti now. Why did the mech put a new injector in?

 

what about a vacuum leak?

 

one of the injectors went bad.

 

Was the fuel injector really bad, or was there a problem with that cylinder?

Which cylinder (injector) was it? Maybe you could start there.