ignition problem, won't start or runs rough

[firstsupra]

I have a real mystery with my 87 7MGTE. One day it was running fine and the next day it wouldn't start. I convinced my self that it was a fuel
problem and put in a new pump. I drove the car a few miles, parked it, and the next day it wouldn't start. I installed my spark tester and found none.
I checked the igniter with the procedure in my Haynes manual and found that only one of the coils was firing. I bought a used igniter on E-Bay.
The car started, but it ran only on about four cylinders. I fiddled with the connections and the spark plug wires and still only had four cylinders.
The next time it wouldn't start at all. At one time during this adventure it appeared to run on two cylinders. So I have a completely random condition
of 0,2,4, or 6 cylinders. I have looked for bad connections or bare wires, but have found none. It seems that any time I touch anything near the coils
or other ignition wires something changes.
help!!!

 

[hvyman]

Have you checked for codes? And not just for a cel.

Is the cps wiring good?

 

[firstsupra]

I checked for codes and it came up with a 12. Something about a crank signal or crank position. Does this engine even have a crank position sensor?
I put all of the wiring back after looking for shorts and tried to start it - no start. I checked the primary side of the coils and they were OK. I checked the cam
position pickups for resistance and all three were OK. Hit the key and it started instantly. Went for a drive and it never ran better. Restarted several times.
Wiggled the wires and connections and it kept running. OK, now what? Do I call Ghost Busters?

Different subject. I have asked several times, but have never got a straight answer. What is normal oil pressure for these engines?
I use 5W-30 Valvoline. It is 40 PSI cold, 30 PSI down the highway and 10 PSI hot idle. Is this normal?
thanks!

 

[hvyman]

Oil pressure is normal. Hot idle is 4.3 psi. After 3k should be above around 38psi.

Sounds like you had a bad connection at the cps connector. Its common from all the heat.

7m has 3 pickups in the cps. 1 for crank position which is the ne signal and 2 for the cam position which are the ge signals.

 

[firstsupra]

It all makes sense now. Thanks so much for a logical, experienced answer to a puzzling problem.

 

[Nick M]

I checked for codes and it came up with a 12. Something about a crank signal or crank position.

Something about? The CPS is cam position sensor. The PCM is not getting the signal. This is why when you wiggled the wires it started. They (wiring) need to be replaced.