I have a 1994 e320, the problem started after i pumped regular gas in it. then it started idling up and down only when in park or neutral. then after time it started doing it in drive a little. i stayed like that for a while.
I cleaned the intake with intake cleaner, i changed the aprk plugs with the best bosch + 4 plantinums, and no change. i changed the maf then the revving an idling just got faster, but not fluctuating as much. but it really gets bad in drive when stopped, ( looks like i have hydraulics).
the car is still hesitating like crazy, i even tried fuel injection cleaner.
the idle will not settle in the 700 zone, it keeps howing rough idle.
i even checked the egr valve with a vacuum, seems fine.
now i have no check engine light, i did before i changed the maf.
any ideas?
thanks

<< i changed the aprk plugs with the best bosch + 4 plantinums,>>

Wrong plug for this motor.
You want Bosch F8DC4 and for starters, change the plug connectors under the coils.

Do a Search on it w/search feature.

when i bought the plugs those were the ones listed, along with the normal bosch ones, they said they are the best ones on the market.
so you think I should change the rubber parts under the 3 coils? and keep the bosch +4 's? b/c the plugs were pretty pricy also and i didnt have to gap them b/c of the 4 heads. but you do have a point.

Do a Search on Plats in a 104 engine and you will have enough info about their faiulure to fill a NY City phone book..
I repeat..you want the Bosch Supers the el cheapos along with new plug connectors.

Seeing that you are new , I will start the search for you..

http://www.peachparts.com/shopforum/showthread.php?t=180605&highlight=f8dc4

thanks man, it all makes sense now. i will change my plugs and boos tomorrow, i called the dealer, they have them. i will just install the bosh platinum +4's in my infinity qx4 97 since they take hte same plugs. i had a feeling it had to do with the ignition system b/c it felt like that kinda rough idle. so i just need the normal bosch non platinum plugs right?

Right...Bosch Super Copper-Standard plug
F8DC4

104 engines hate platinum...they throw-up if you even mention platinum

I see that Bosch is saying that F8DC4s are no more, replaced by 7927s, a part number that has no character at all.

http://www.boschautoparts.com/Resources/VehiclePartFinder/

Getting harder to find ..some NAPA stores still have them .
Many are going over to NGK .. and even Champs..

they have them at the dealer ship, they have the copper inside. i bought some today. i found champions at other places for half the price, but i thought i'd get the bosch to be on the safe side.

Cool
If you plan on keeping the car for a long time, go get another set.. they are running out...
Time will tell of the replacements Bosch has come up with do the job the Super Coppers did ..they were great..maybe too great !!!

hi i just changed the plugs back to the ones you told me about. it got a little better. its not idling fast or way high and way low. but the the idle is still not settling, still goes up and down a little and i can feel a slight backfiring when in idle. any ideas what it can be now?
i checked the boots for the coils, they looked ok. i accidentally ripped the casing for a spark plug wire when i was screwing the cover on, you can see the threads sticking out, so i just used electrical tape on it for now.
let me guess, is that my problem?

<>

How can you test the boots looking at them ??
They are a resistor connector.

I thought you were going to change them?

i bought the plugs, they didnt have the boots for the coils. i think im just gonna get the whole set. but im starting to think its not from it. b/c i just took it apart again. i noticed when i play with the idle cable ( adjust it) it goes away, but only b/c the engine is revving higher. but if i set the idle cable to the normal position, the rpm starts going up and down lie crazy in drive when stopped, like it was doing before with the platinum plugs.
i also noticed the screw holding the thin metal pipe tha goes to the egr was loose, when i tried to put it back in, something inside the engine was hitting it, maybe the pistons. do u think possible i have a problem with my fuel filter also? or anything electronice that might be burnt?
thanks

also i checked the codes using the onboard coder by the battery, and i got code 23 now.

Your code and condition indicates you have a vac leak.
However , the reason we start with the correct plugs and the coil connectors is b/c without a scope, they are hard to diagnose , so this is one of the few times it is best to change them [ specially the connectors, due to their failure reputation and low cost]..
Look for a leak, but I would still start with the 3 connectors under the coils..
You can not look at a coil connector and see if it is good/bad.
You have a Scope?????