stutter from 2000-3000

[upstate914]

I am new to this game, but I have a stock 72 1.7l, I have replaced stock ignition with pertronix. I have however devolped a stutter at 2500-3500rpm. It does not do this all of the time however. I have read that a bad tps will do this. I removed mine and sure enough there were tracks worn under that contacts, I then cleaned them and bent them to align with a clean track. THe problem is much better,but still exists. I am sure the tps is not up to full snuff, but do you think this may be the main culprit or should I be looking somewhere else.

Thanks

[3D914]

Upstate,

The Manifold Pressure Sensor could be a possibility as well. I suggest connecting a vacuum gauge just ahead of the MPS. Mount it so that you can monitor it while driving (or with the car on stands). Note what happens to the vacuum between these RPMs.

[upstate914]

Pelican shows that these parts are nla ??? THis seems to only occur during a load, not during a "rev" situation. DOes that help

[bowlsby]

There are also weights in the bottom of the dizzy which stick if they are corroded. Add 1 drop of 30wt to the felt in the center of the dizzy shaft....after cleaning the crud out.

[Scooter311]

Howdy!
Sorry I can;t help with your question, but by Upstate, do you mean Upstate NY, and if so whereabouts?
I'm in Rochester.
Cheers,
Jeff

[upstate914]

The wonderful town of Hornell NY. THis is the 2nd summer with the car, it just seems that I don't have the faith yet to take it on long runs, if I can get through this stutter problem I would feel better. I am going to check for vacuam leaks on the mps and perhaps shop for one during the winter on this bbs.

[John Rogers]

As has been noted, replacing the FI trigger points cured the problem This has happened several times with our 1974 2l and I finally noe just put it new points FIRST if it starts to run rough or miss. This has cured the problem everytime. Good luck

[upstate914]

Let me clarify I replaced the points with pertronix. That does not effect the trigger points. Are you thinking trigger points may be a cause?

[Jared at Pelican Parts]

upstate, there are TWO sets of points on your car. One is on the top for the ignition, then there is another set on the bottom that is used to time and trigger the fuel injectors. You'll see two flat-head screws holding a curved plate on the bottom of the distributor. remove these and pull the plate out, you'll see the points assembly.

The 1.7 MPS is NLA, however a 2.0 MPS will work. The only difference between the two is calibration. If you re-adjust it using a CO meter you should be fine.

Other things to check,

-all vacuum hoses, obviously. Especially the small "t" connector from the Aux. Air Reg. to the intake plenum. Also check the gaskets between the intake runners and the heads.

-Engine grounds. Cleaning these in the past has cured a lot of problems for me. Just hit it with some WD-40 and emory cloth.