Hello all, happy 2025!
My 88 V12 has had major difficulties starting this winter. I read the threads, but could not quite find a similar case.

When it started, it would blast a big cloud of blue smoke that would only disappear after running it for a minute or two at 3000-4000 rpm and no longer do that when used withing half a day. After it had heated up for a few minutes, there would no longer be any blue smoke and the rpms would be normal, 1500 at first to go down to the standard 500 when the engine was at temperature. Each time I charged the battery to full to make sure it would get maximum power from the battery.

However, when rpms were turned down too quickly the engine would die. Then it would only start after a very prolonged cranking, which I regretfully did. On a few occasions it would then click but not crank. After a while, I tried again and it would crank, but with difficulty, requiring prolonged cranking.

This has been going on for a month, until, I figured I should preheat the engine as well as the battery with a little electric blow stoves. That worked quite well, so I have been succesfully doing that for a couple of times. Now, all of a sudden it does not want to crank at all anymore after the heating and charging, while it does make the click sound, so it must get power. I had run it the previous day while it started fine after the heating and battery charging procedure.

1. Could this still be a wiring problem, or is it more likely that I burnt me starter.
2. If the latter is the case, does the steering rack and transmission really have to be removed to get to it?
3. What can cause the engine to have such difficulty to get started in the cold, blowing blue smoke of several minutes?

 

Blue smoke = burning oil.

The scenario you've described sounds like leaky valve seals. Overnight the leaky seals allow a bit of oil to accumulate in the cylinders which is burned-off on the next start



Are you hearing the starter click? Or are you hearing the starter relay click?

If the starter clicks but doesn't actually turn the engine then, yes, it sounds like the starter has heaved its last breath.

If the relay clicks but the starter does not click then, again, the starter might've died. Or.....the relay is clicking but not sending voltage to the starter. The relay can be bypassed by applying 12v "+" directly to heavy white/red wire. If the starter now operates then you have a relay problem.


Poor grounds and loose/dirty connections are always a possibility. Check/clean/tighten them all before spending money on new parts.


The CTS (Coolant Temp Sensor) plays a huge role in cold starting as it commands the needed rich mixture...akin to an old fashioned choke on a carbureted engine. The CTS can be test with a DVOM. Or.....simply replaced on speculation. Only takes 20 minutes and costs $25 or so. As guesses go the CTS is painless.

But......

There are other possible faults and/or a stack-up of different faults. Old spark plugs. Weak ignition coil or other ignition weakness. Dirty or incorrectly set throttle bodies. Low fuel pressure.

Cheers
DD