My jerky Lincoln

I have a ratheer unique problem with my 1999 Lincoln Continental. The car jerks/ misses when it goes into 3rd gear at about 35-40 MPH. It feels a lot like trying to drive a standard transmission in 4th gear at 20 MPH. Once the car reaches about 60-70 MPH it smooths out but even then there is a slight jerkiness. I had the transmission rebuilt but that did not solve the problem. Since then I have tried new plugs, new coils, a new fuel pump and replaced the fuel filter all to no avail. The computer is showing no codes and everything appears to be running within specifications. I (and the “Experts”) I have worked with are stumped. Anybody else out there with a similar problem that has been resolved.

Maybe it’s time for a compression test.

I don’t know too much about the transaxle in the Contis. It must be a real pain to you that it is still doing this after someone led to to invest in a trans rebuild, not to mention 8 new coil$! Was the fuel pressure low? It sounds like someone is doing a lot of guessing.

You must have a tach in this car. What are the rpms doing when it is “jerking”? If you get no joy here, I suggest

Circuitsmith: I hate to think I could be looking at a cracked head. From your experience shouldn’t I be looking at a jerkiness that occurs thruout the transmission shifting cycle not just when it reaches “lock-up”? What do you think.

Thanks. webnicks

not just when it reaches “lock-up”

I didn’t get that from your first post.
It’s beyond me how a transmission could make an engine misfire.
Low compression (without oil burning)can be caused by a valve problem or a head gasket,
not just a cracked head.
How did the old plugs look?

A couple of the plugs were covered with oil and a couple were somewhat rusty. Otherwise they looked fine. I also forgot to note that this problem is much more pronounced when the engine is hot instead of cold if that helps. Thanks for your analysis. I look forward to any additional thoughts you have.

The oil and rust were on the outside end of the plugs?
I still think a compression test is the next step.

“like 20mph in 4th gear”. Bad compression - insufficient torque to smoothly carry the load. Was that you’re first thought? If not, what words make you think compression?

The question that comes to my mind is why the car would only do this when it enters third gear and then only badly when the engine is hot?