1990 740 sputters then dies in rain

if you had this leaking issue between paravan and hood it is a good idea to take the dizzy cap off completely and clean/dry it inside and outside. Both the red cap and the black cap that sits over it. There might be residual moisture between the caps causing intermittent leaking of HT-energy leading to missfires

They were both brand new before I had this issue. Less than a week since I installed them. It's now been three weeks since I installed the new CPS and I've not had the issue persist. My only concerns are an intermittent long crank time and the car intermittently breaks up when I'm boosting over 10psi.

DavePolyakov said:

My only concerns are an intermittent long crank time and the car intermittently breaks up when I'm boosting over 10psi.

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if the check valve on the main pump won't hold pressure it will take a longer time cranking to start

If your spark plug gap is too large. That can cause misfires under boost. Try using .028" gap.

Will pull my plugs and check the gap. Thanks for the advice

dl242gt said:

If your spark plug gap is too large. That can cause misfires under boost. Try using .028" gap.

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I was driving in my old 740 during a rainstorm and had to drive through a big puddle because I couldnt switch lanes. I was running IPD lowering springs so, closer to the water haha. When I woke up the next day and turned it on, it was puttering and sputtering. Sounded like stomach ache farts. Anyway, I checked the spark plugs and spark plug wires - discovered that water has affected 1 of my spark plugs and moisture was inside 2 spark plug wires. I changed the spark plug, checked every other one too, dried out the spark plug wires and opened the distributor and sprayed a little wd40 on it to remove any moisture. After that, the sputtering and puttering stopped and it ran smoothly again.

Pulled my spark plugs they each had a gap around 0.028-0.030. I noticed the threads were oily. I've been told by my friends that when I'm boosting in front of them on the road they see black smoke pop from the exhaust. Is this lh2.4 dumping fuel when it sees more than 7psi? Some TLAO chips may help?

Might be that the PCV system is not working well. That puts some oil into the combustion chamber.

I just cleaned all PCV components. The plugs look ok though right? The issue probably lies elsewhere?

dl242gt said:

Might be that the PCV system is not working well. That puts some oil into the combustion chamber.

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Yes, I agree that the plugs look ok. Maybe try a slightly thicker oil like 15-40w and see if that improves. You can also with a cold engine remove the intake hose and check the turbo for excessive shaft play.