O.K. This will be a bit lengthy. But first, it's never worth the cost to do so much work on a motor with over 100K miles. That would be like getting out of the shower and putting on your dirty clothes. You'd be better off buying a used motor with 30-50K miles. This'll usually run you $1500 and come with a 12-month/12K-mile warranty.
PO340= Camshaft position sensor circuit. This could be the sensor is shot, the wiring/connector is damaged, or the computer is bad.
PO420= Catylist effeciency. This could be your converter is shot, the 02 sensor is bad (your most likely cause), or an exhaust leak.
PO700= This is a code telling the computer that there's a code inside of the transmission control module. You'll have to have a seperate scan done on this computer. AutoZone doesn't have the capability to do this. You'll have to go to a shop.
PO736= Transmission gear ratio error. This could be your vehicle speed sensor is failing, the internal line pressure is low inside the transmission, or the clutches for that gear (1st, 2nd, etc.) Are slipping.
PO841= Transmission pressure switch error. This could be the pressure switch is bad or the line pressure is low.
With the combination of your trans codes, I'd say your transmission's clutches are burnt and the fluid is contaminated, causing the internal passages to become clogged.
You'll definitely have to have that checked out.
If I've helped you, please take the time to vote for me, as my reputation pays my bills. Thanx, Ernest.
Friday, February 19th, 2010 AT 8:44 AM