check engine lt on , idles rough, bogs down when you try to accelerate

[DesCal]

I just purchased a 1993 740i with 160k, presently it only goes 5 miles per hour, and im waiting for a repair manual to show up.I bought this from a lady in santa rosa who at first thought the tranny was going out and had a friend take it to his house with the thought that he might buy it. The friend drove it to his house and said it drove like a dream. he said he was going to get it smogged so he put some kind of additive into the fuel that guarenteed it to smog with a full tank of gas.the next time he drove it it ran for a while and then it cut out and ran intermittantly until in its present condition. he said that he thought it was the computer. has anyone had a similar experience and if so what is the fix? any help would be greatly appreciated.

[INFAMOUSNEEK]

read the codes.. if it only goes 5mph.. could be the traction control is messed up = unplug it and VOILA.. most confuse this for tranny issues like described..

[epmedia]

Change the fuel filter first, Robert

[obnoxious2]

Should have gotten a PPI.

[lithium726]

the 'additive' could have fouled up the O2 plugs.

[DesCal]

Should have gotten a PPI.
so far I have bought the fuel filter,service manual ,spark plugs,oil filter air filter. any way to check o2 without a code reader? and what is a ppi?

[MrBen]

To check the O2S use a voltmeter and check the voltage at the O2S, it should constantly switching in between the .1-.9v range.

PPI - Pre Purchase Inspection