Bucking and jerking

[qtdr]

I have a 87 cont. that bucks and jerks during deceleration. I have adjusted the TV cable from one extreme to the other. The transmission shift points will change and the shift smoothness will change, but the jerking and bucking always remains. Any help would be greatly appreicated.

Thanks.

[pro-five-oh]

If it happens around 50mph its probably the TFI module on the distributor. Read this:

http://www.coolcats.net/tech/troubleshooting/tfi.html

[gadget73]

What kind of condition are your plug wires, and the cap/rotor in? Is the top of the coil corroded by chance?

[Steve Moran]

I'd go with eather or both ideas I have had a new set of plugs give me the same problem you are saying, mine happened at a cretain RPM range as tho the engine had would reach a certain un-harmonic convergance and things just did not mesh. (sounds kinda hippyesque) but that is what happened.
The plugs would misfire only in a certain RPM range.

[qtdr]

Thanks for the replies. It does occur around 50 miles per hour. I have new plugs, wires, cap and rotor. Will check the coil and tfi module and let you know.

Thanks again.

[pro-five-oh]

Replace the TFI module with a Ford Motorcraft part, nothing less. Can't skimp at that location.

[qtdr]

I replaced the coil and the problem was deminished but not completely gone. Next I replaced the TFI and that helped even more. Now it is much much better, but not completely gone. I pulled the codes and got 34 in KOEO and 34 in the continuous memory and 34 and 94 KOER. Is the vacuum solenoid for the EGR and the air pump system the same solenoid. In closing I would also like to thank you guys for you help.

[nicholas77586]

I dont know the SEFI engine as well, but if it has a smog pump there should be a refief valve that opens or closes during decelerations to prohibit backfires and such. Just a hunch, sorry if there isnt a smog pump on these cars, my 84 has one.

[pro-five-oh]

Code 34 is usually a worn out EVP sensor...that's the sensor that bolts to the back of the EGR valve.

Replace it, clear codes, see what happens. It should be all clear by then.