I have a 2004 DOHC 24V Mercury Sable that lost all gears and had the transmission replaced after it was ascertained that the tranny had gone bad. I think the Sable and Taurus are quite very similar.

After transmission was replaced, the car runs but misses and does not seem to have much power. The front two ignition coils (on the spark plugs) were swapped but the miss is still present. The CEL light also came on with codes P2270, P0351, C1298, C1299 and C1297. Any help will be appreciated.

 

Depending on who changed the trans, they need to recheck their work for wires not connected or pinched. The codes involve wheel speed sensor signals and voltage to the ign coils. Look for any ground wires that might have been overlooked and not connected, rough handling of wiring in general.

 

Thanks Hanky for the suggestions. I will tell it to the guy who changed the trans. So, the problem is not likely a tune-up issue. Moreso, that the car was running without this much of a miss before the trans went out.

In addition, I noticed that when I plugged the exhaust outlet (post the muffler) with a rag, the engine does not seem to want to die or stall, rather there's a high pitched sound from about the exhaust pipe connection upstream that may suggest considerable leak The exhaust pipe was disconnected upstream during the trans replacement. I'm thinking this may be responsible or contribute to the misfire/stalling and loss of power?

Also, as in the attached pictures, I noticed that a big bolt or screw is missing. However, the guy who changed the trans said the connection on the replacement trans is somewhat different from that on the old trans. And that the replacement trans is otherwise well mounted and the absence of the bolt as in the pictures should not be a problem. I'm wondering if this is a cause for concern?

The attached images are of the engine compartment near the firewall. The 2nd image is a zoom of the 1st.

 

What was the replacement transmission from? Year/make/model? The Taurus/Sable are siblings, but don't always like to play together.

 

Update:
After using his code scanner, the repair guy insisted we start with tuneup - new spark plugs and new ignition coil for cyl #6 . Iridium NGK plugs (Motocraft unavailable at the time) were used and while at it the PCV valve was also replaced. Afterwards the misfire went away and code 0351 did not return. However, the leak about the exhaust pipe was still very noticeable.

Then the exhaust pipe leakage was welded, tire pressures adjusted and the codes were cleared. After driving about 40 - 60 miles, only the P2270 code came back. Now, when I'm driving to a stop or coasting downhill, the engine rpm will increase and sometimes stays up for about twenty seconds or so.

Regarding the trans, the repair guy told me the replacement came from the same type of car but with lower miles on it. He asked for the VIN #, specs for my car and location of the gear handle. However, I will follow up with him to the exact car specs the trans came from.

The trans seems to be shifting well overall, although with a slight jerk from first to second gear.

So, code P2270 has returned!!! Your suggestions are highly appreciated.

 

The P2270 is Bank 1 down stream O2 sensor. Double check its connection or damage from the tranny replacement. Bank 1 will be the firewall side of the engine.

 

Thanks for the input. I'll check that O2 sensor and replace as necessary. Right now the CEL (P2270) went out on it's own, but the power still seems not as great.

Just a note: it seems that O2 sensor is very sensitive to water, as in from rain or car wash.

 

The connector may not be fully seated. Put some dielectrical grease on it and snap the connector back together. Could also have a hairline crack in it. I had that issue on my 88 Ranger when I had the clutch replaced. The Dealership cracked the O2 sensor than tried to get out of replacing it on their dime.