Crank No Start- Already tried the basics

[e30vert]

88 325 ic (vert) M20B25

Crank - No start. Just got the engine running again after reassembly. Did the swapped plug on the CPS with the Speed Sensor initially and then figured out that they were switched. Engine ran.

Then I was moving the throttle up to increase engine heat and get over the 1/2 way mark on the temp gauge to make sure my Electric Fan and Radiator Sensor were working proper. Engine ran over the 1/2 way mark and fan never kicked on. Shut the engine off and coolant bubbled up and over from the reservoir. No biggie I thought. I will just let the engine cool - add more coolant and then fix the wiring connections to the Electric Fan. After that engine would not start. When engine was running it was making a sound as if the starter was staying engaged. Not a whine or anything , but more like it was just spinning fast at idle.

Fresh Oil topped up to correct level
Fresh Coolant - Topped up to correct level
New Distributor cap and rotor
New CPS - Metal canister style - Measured the resistance on the CPS from pins 1 -2 with a Multimeter and it read 540 Ohms (This appears within specifications)
Every vacuum hose and fuel hose tightened with new hose clamps
New Intake elbow as well as small rubber hose off of the Idle Control Valve (ICV)
Cleaned out inside of ICV and it DOES humm with the key turned to the ON position
Cleaned off the contacts on each of the pins for the 3 relays - Main - Fuel Pump, and O2 Relay
Pulled fuel line off of Fuel Rail (passenger side near top of Intake Manifold) and placed a cup under while I cranked the engine. Filled the cup fairly rapidly. Assume fuel pumps (primary and secondary) are working correctly.
Pulled off the rubber boot for the coil and then the center plug and placed it right near the center plug in area on the coil while I cranked the engine over. SPARK WAS SEEN bridging the gap across .
Pulled Main Relay out and jumpered pins 30 and 87 on the receptacle. Cranked engine . No Start. Reinserted Main relay.
DME does appear to be getting power as the CHECK ENGINE light on the extreme left side within the Cluster lights up when the key is turned to the ON position.

Next thoughts are to T in a fuel pressure gauge to see if fuel pressure is correct at the fuel rail.
Purchase a replacement CPS and install it to determine if my CPS is faulty even though the resistance of the current CPS is within Specification.
There is an aftermarket stereo and alarm system installed with Ignition Immobilizer that I "think" I enabled when installing the alarm system. Remote Arms and Disarms as it should though.

I need some helpful guidance on next steps . This issue is starting to stump me , but I am un deterred.

[iansane]

If you've got spark, I would imagine you're wiring/dme/cps are all functioning correctly. Have you pulled a plug to see if it's wet(ie, getting fuel). I would look to see if the rotor is turning.

[e30vert]

Thanks Iansane! Fired right up this afternoon. Super weird.
Filled Brake Fluid up and pumped up brakes. Does not seem like I need to bleed em. So thats cool.

Alternator may not be working correcty. Even though its a rebuild. Reads 12.26 volts when engine is not started and drops to 11.94 volts when engine is started so Alternator is not doing its duty. Perhaps I have the leads connected wrong?

All my lights are on within the Cluster after start as well - Check Engine , AntiLock, Brake (when I take the parking brake off the light dims , but does not go all the way out), Brake Fluid, Battery (this must be a result of the Alternator. Belts are tight with no slippage and pulley , alternator pull spinning well.
Anyone have a connectivity diagram for the Alternator?

[e30vert]

Ive checked the Blue Wire that is the Exciter Wire that is disconnected on the Alternator and it has 12 volts when the Ignition is in the Accessory position.

When I hook the Blue Wire back up and then start the motor the voltage is then 1.45 VOLTS. This is wrong and will not allow the Alternator to charge the battery and provide current to the needed circuits.



Took the Alternator out and had Autozone test it. They said it passed.

I have tested for continuity from the large wire on the Alternator to the Positive Post on the battery and also where it connects to the Starter Motor. I do have continuity .

When I pull the negative lead from the battery after start up the motor dies so I know the Alternator current is not making it to the battery and other circuits.


I do not have a ground lead hooked up to the Alternator as its my understanding that it finds chassis ground through the body of the Alternator and Alternator bracket.

There is an exposed threaded post on the Alternator though. I wonder if thats for a ground strap?

I also read that if the Starter cables / Wires are hooked up incorrectly that it can cause this issue. Does anyone have a diagram or picture to share of the starter wiring that is proper ?
The starter works to rotate the engine and start the motor . On one start it will leave the starter engaged and then the next subsequent starts it may be engaged or disengaged.

[e30vert]

I tested for continuity to ground from the post on the Alternator and it is showing that it can find ground.
Gonna check my starter to make sure the wires are installed correctly. I do have the Large Black Wire and Red wire * thick gauge* connected to the large post on the starter that is farthest away from the engine block.

I am also thinking that the starter may not be grounded from the face of the starter to the face of the transmission as I powder coated the case of the starter and that may be preventing a good ground connection.

I really dont relish the idea of removing the starter just to grind the face of it down and was wondering if there was a way to run a wire instead?

[e30vert]

Figured it out!
After I thought about how well I had checked the placement of the wires on the starter I checked them again very carefully with a light and found that I had actually connected the big RED Wire from the Alternator incorrectly.
I had connected it to the large post on the starter that was nearest the engine block and not the outer post with the heavy gauge Black Wire that routes from the the batteries positive terminal.

Once I connected the RED Wire to the same post (outer post on starter) as the Black Wire then the Alternator now charges the battery as it should. Also the lower red warning lights in the cluster all turned off after startup as they should.

This issue was completely self-inflicted and it turns out to be a common mistake. LOL

I want to tag this so others can learn from my mistake, but not sure how. Feeble attempt below

#tag
Alternator not charging
Starter Wire Connections
Alternator
Starter