Runs rich, wont rev past 2-3k

[240DL?]

It runs way to rich cold or warm, but once I get driving it it fouls the plugs to the point it wont run. I have pulled apart the harness connectors and cleaned them all. If I remove the connection from the CTS it will run much richer and most of the time die.  I Replaced the sensor when I first got the car.  It reads about 330 ohms at operating temp at the ECU (13-ground)

[Zed Head]

 

6 hours ago, 240DL? said:

I will check ignition timing again but I know everything else mechanically is sound, what makes me think its an EFI issue is how rich it runs. I still will look into the ignition system like you mentioned as there are a lot of old parts that I cant speak for there condition. 

I explained earlier how a bad ignition module can make it run rich.  Too many sparks.  It could also cause rev limiting.  Overheating.  You said that you've tried both AFM's and both ECU's.

The distributor is simpler than it seems.  A six-spoked metal wheel that has teeth that pass by a magnet.  Check the air gap, the resistance of the pickup coil, look for kinked or broken wires.  You've kind of worn out the ECU's and AFM's.  Ignition will seem like a vacation.

Edit - could also be two bad ECU's.  Running rich and sudden dying are two signs of a bad ECU.

Edited February 19, 2018 by Zed Head

[240DL?]

I'm reading the distributor section of the FSM now and will measure the air gap.  If I cant find any problems there ill try running it till it dies then swapping ECU's and seeing if it starts again.  

[Zed Head]

Does the tachometer behave normally?  Smooth, seems to correctly match RPM?  The tach needle is a clue to ignition problems.

[240DL?]

I just popped off the cap and rotor, the air gap seems to be .279mm (within spec), while looking at the FSM I see the 2 pickup type has a phase difference. While checking this I am told to remove the red wire from the "water temperate switch". 

My thermostat housing doesn't seem to have this

Instead it has what I believe to be a colling fan switch from another Datsun?!?

 

Another housing I have in a box might have the right one, but I have no idea where this red wire it should be connected to is... FOUND THE RED WIRE

 

Does the "water temp switch" actually effect timing (1976 federal manual transmission car)

 

Edited February 19, 2018 by 240DL?

[240DL?]

52 minutes ago, Zed Head said:

Does the tachometer behave normally?  Smooth, seems to correctly match RPM?  The tach needle is a clue to ignition problems.

I believe its correct, Ill have to get a timing light with an RPM readout to make sure. But it doesn't seem like it would be 1.5 times the reading like you mentioned before. 

[Dave WM]

have you tried listening to the fuel injectors with a stethoscope? hear the clicking while running?

[240DL?]

9 minutes ago, Dave WM said:

have you tried listening to the fuel injectors with a stethoscope? hear the clicking while running?

With a screw driver yes, they are defiantly pulsing as intended, not sure if its too much just by sound

[Dave WM]

well lets break it down

fuel pressure right

AFM seems to check out

injectors pulsing

Temp sensor resistance matching FSM guidelines

compression and timing ok

think you said tach seems correct

and you have massive over rich conditions based on spark plug readings.

Testing everything to the FSM at the 36 pin connector should clear wire harness (some of those pics show a lot of nasty looking corrosion).

for EFI issues:

I would think maybe bad or wrong ECU or wrong fuel injectors. Trying to test both those (beyond clicking and spraying) is something I don't really know how you would do other tham substitution, which is a costly way of checking things.

can you take some pics of the overall engine bay maybe something just being over looked.

did you try removing the oil filler cap on the valve cover. A correct setup will run rough and die in a few seconds due to massive ail leak (the PCV system is sealed).

only other thing I can think of is the spark actually getting to the plug? wet fuel soaked plugs could be non firing plugs. I assume you have check for spark AT the plugs.

doing a power load test or just pulling them all out and looking for spark at this point.

 

 

 

 

 

 

Edited February 19, 2018 by Dave WM

[Dave WM]

are the plugs showing as over rich (black sooty) or wet (raw gas).

[240DL?]

1 minute ago, Dave WM said:

I would think maybe bad or wrong ECU or wrong fuel injectors. Trying to test both those (beyond clicking and spraying) is something I don't really know how you would do other tham substitution, which is a costly way of checking things.

can you take some pics of the overall engine bay maybe something just being over looked.

did you try removing the oil filler cap on the valve cover. A correct setup will run rough and die in a few seconds due to massive ail leak (the PCV system is sealed).

only other thing I can think of is the spark actually getting to the plug? wet fuel soaked plugs could be non firing plugs. I assume you have check for spark AT the plug.

 

 

 

 

 

 

Ill take some pictures of it, and get some part numbers on injectors just to make sure they arnt the turbo ones. I have the PCV system disconnected because of a vacuum leak at the timing cover that I am yet to correct. I have pulled the wire off the plug and thrown another in it to test and it had spark against the valve cover. 

[240DL?]

2 minutes ago, Dave WM said:

are the plugs showing as over rich (black sooty) or wet (raw gas).

It has black soot until it dies from running rich, then wet and smelling of gas