This 1983 280zx turbo engine has had a ignition miss. While running the engine, I'm getting intermittent spark to #1 and#3 plugs. I pressed the side of the distributor housing with a large screw driver and the spark came back as long as I held it. Any ideas of what to think of this? If the bearing in the distributor is worn, is this a common result. Really don't want to buy a new one, MSA wants about 300 dollars. Also, I looked under the dust plate at the "wheel" with the slots in it. It looked ok. Any help would be great!

Worn distributer cap maybe?

Or worn bushings on the shaft that is causing the air gap to change. When you push against the side of the distrubutor body you may be bringing the shaft back into the alignment that is required for the proper air gap of the reluctor to stator clearance.

If the air gap changes, you will have a missfire just like if you had a loose set of points, the larger or smaller the gap, the less electricity is conducted, causing a missfire or no fire at all at the plugs.

Seems like a possible cause at least ....

Well it has to be either one.

Best to test by removing the cap, firmly grasping the rotor button and checking for shaft play by attempting to move the button left to right.

No play then most likely the cap, if there is play in the shaft the problem are the bearings.

At this stage I haven't read of anyone actually being able to find replacement bearings, so the best option would be to find a suitable replacement at a wrecker.

Thanks for the info. The cap is new, and had the same problem with the old one. That sort of leaves it either bearings or something going on at the "pickup". I haven"t checked the connections were the wires plug into the "pickup" yet. Just maybe pushing on the side makes the connections move slightly. The shaft seems tight when pushing it side to side. Going to have my son crank the engine and watch for signs of wobbling.

Chloe has rebuilt units if you need one. I just replaced the insides of my '79 dist. It ended up costing me about 2/3 the cost of a rebuilt one from midwestz.com . This is with out a module. If I remember correctly about $70.00 I think she can get all the parts if you want to go that route. What I have found is that the braker plate goes bad , the plastic holders for the ball berrings that are sandwitched between the two disks fail and the ball fall out. this desables the vacume advance for the most part and there are parts flying around when they fall down into the weights spinning below. Then all sorts of bad things happen. Bottom line with a bone yard unit is that the plate is still 25 or so old and the heat has been working on the plasticparts. I bought a secound dist and it had a bad plate also.

The turbo distributor does not have a vacuum advance. I took it apart and checked all I could, cleaned the diode plate and wheel. The shaft bearings seem fine. It is firing #3 better now but still misses once in a while. Not even sure at this point that the problem is in the distributor. Interrmitent problems drive me crazy! Think at this point it might be best to find a used one to see it it helps. You mentioned "Chloe". Who or what is that?

Chloe is the contact person for midwestz.com One thing you might do is to find a module in a bone yard . If not just to see if it is what is bad , but it wont hurt to have an extra . New they are not cheep. But Chloe has vary good prices if you must buy new.