papajam

The clutch cable is connected to the battery negative in the same fashion as scores of other devices; through the body! In this case, gearbox>cable>cable bracket>body>battery. "Are you saying the engine is grounded but the chassis is not?" (sorry, don't know how to multiquote the same post) No. The other way round; chassis is grounded, engine is not (through the preferred path anyway). "The engine would not cut out power even if the Chassis was COMPLETELY disconnected from ground as the ECU is grounded through the intake manifold bolt." Please see previous answer. If the engine is not sufficiently grounded, then the ECU may not see system voltage potential and possibly shut down. Compromised grounds of any kind in any circuit can result in all sorts of sometimes supernatural symptoms. With a bad engine ground, the electric will seek an alternative path of least resistance (if one is available). It might be another wire, a cable or even a hose with high surface conductivity. Could be anything! As an example, the alternative engine ground path for a SPICA fuel injected Alfa Romeo. if there is high resistance in/or a broken engine/gearbox ground strap, is the throttle cable. Quickly and correctly diagnosing electrical faults even with a vehicle in the flesh can be a feat worthy of applause. Diagnosing over the internet introduces even more challenges. So without being able to conduct any hands on testing, my suggested diagnosis is based on knowledge and experience. What would I test if I had the vehicle in front of me? Voltage drops between the negative battery post and cable clamp, battery post and chassis then battery post to engine. And under load if the results dicate it. Same on the positive side if necessary. To prove or disprove results, or maybe to not even perform the voltage drop tests at all, connect a jumper cable (as in battery jumper cables, not a household extension cord) between the negative cable clamp and engine then observe the results (hoping that the post to cable clamp connection is good). Our common goal here is to help f1gelato diagnose and repair the problem while teaching a bit along the way.

Well, a tight connection in no way guarantees a good electrical connection. There can be unseen corrosion affecting continuity. IMO, if the main power wires under the dash were grounding, I'd think that the wires would arc and perhaps blow some fuses. The OP states that the clutch cable was arcing, not any wires, and the arcing stopped when clutch pedal freeplay is taken up (ground circuit now being completed through the pedal). Another clue is that the arcing started only after the battery was changed without any work having been done under the dash.

I think you may be confusing full strength antifreeze/coolant with the plethor of 50/50 pre-mixes that are available. Neither the Prestone, Valvoline (Zerex/DexCool), Peak or Dow Chemical websites say anything about their products being made to be mixed 50/50. On the contrary actually. All give a range of percent concentrations that can be used to obtain the end users freeze and boilover protection requirements. But, it is obvious that my quick search did not reveal a manufacturer whose product is made to be combined 50/50. Please provide a link(s) to a product(s) that is made to be combined 50/50.

^^^This^^^ The clutch cable is providing the main electrical ground, not the battery cable.

Good show, Db! Congrats. The 'system' is an evolution of the mechanical inertia switch used by many manufacturers in the '70s & '80s. The resettable switch would open the power circuit to the fuelpump in the event of a crash to prevent the pump from emptying the fuel tanks contents on the ground (or feeding a fire) should a fuel line rupture. Same principle is employed in newer cars with only the method of power interruption being different. Some cars use a relay activated by the ignition system. Others are triggered by the ECU (which may then trigger a relay). In all cases, an engine running or engine start signal is required to power the pump full time. KOEO (Key On Engine Off) will initially power the pump for only a second or two simply to pressure up the fuel rail. There is no pressure switch for the fuelpump.

Dumbest question ever asked. Is there fuel in the tank?

They certainly don't have mine under control! I've had not one, not two but THREE slow responding cam codes (P000A, B & C) in the last 2500 miles. The Oil Control Valves (OCV) were switched side to side the first time when the P000B code came up, then an OCV was replaced with the P000C code and just yesterday, another OVC was replaced for the P000A code. The dealer told me they've never seen this before and are "guessing" that it's the oil I used at the first oil change at 800 miles. I ain't buyin it!

My response on the starter was based on the following clue. There are a number of failure modes that can have the armature spin and not engage the pinion. These include a broken pullrod, pivot fork, fork hook, fork pins, pivot bolt/pin, etc. A failed sprag clutch in the starter drive could have the pinion engage and not spin the engine as well (but would sound bloody awful!).

Sounds like the starter drive (the pinion to be exact) is not engaging the ring gear (on the flywheel or flexplate depending which gearbox is in the car). Could be the starter or the ring gear is the problem. What were the symptoms that prompted replacing the starter, alternator and battery in the first place?

That could be the issue. Syncros work on the principle of friction. Most modern GL-5 gearoils have too much EP (Extreme Pressure) additive that makes the oil too slippery for some types of syncros (Porsche for example) or worn syncros to function properly. Redline NS (Non Slip), as 1 Lucky Texan posted, has less EP in it thus allowing the syncros to better do there job.

Which type of Redline 75/90 did you put in?