CIS low rpm hesitation after heavy rain. Why exactly?

[bigchillcar]

Hey,

My car sat out Saturday and Sunday in a pretty steady rain and it's been cold (40's and 50's). When I went to start it last night to go home, at stoplights it would hesitate and died at least once on take-off. As long as you don't goive it too much throttle, just enough, it will go and as soon as you get up into mid rpm ranges, it pretty well settles down.

I've seen this before in similar weather last year and it seems to just work itself out after the engine has warmed up and dried off. I'm just wondering what exactly is the cause (technically) in my CIS car.

Thanks,
Ryan

[bigchillcar]

Bump. Come on guys, I know this seems a moronic question. Of course we all 'know' that they tend not to like very damp weather, but am wondering if there are any 'weatherproofing' strategies I could employ on the sensitive components.
Ryan

[Targa77]

What was happening to mine was that after washing my car, water was getting into the spark plug socket and shorting out the plug. Check the rubber grommets on your Beru connectors and make sure that they are sealing properly. I also sprayed WD 40 on my distributor cap and wiped off the excess with a rag. I hope that this helps.

[targa80]

You could check to see if you have a high voltage leak from your spark plug wires. My car ran ruff in wet weather and when I checked I couldn't find anything. I then cheched it again at night time, I was surprized to see several locations that arching was taking place at intermittently. I replaced the wires and that problem went away.

[ohecht]

Mine has the exact same problem...but my wires are relatively new Magnecors. I have suspected mositure is getting in somewhere, but I have not had a chance to look into it closely.

[bigchillcar]

I'll have to try taking a look at my plug wires at night for arcing. I had been thinking about the distributor, as I've seen water on the cap after being out in the rain, but I'd guess that it would have to get up under the cap and inside to cause problems? Then again, maybe it's just such a large moisture content in the air/fuel ratio that gets screwed-up until the motor is hot enough to evaporate away most of it...

Ryan

[Pillow]

Magnecor wires are super sweat! I run them on my VW and cannot wait to put a set on the 911.

Mine has moisture problems as well, but not sure what to do about it... Thank God it is always covered at home or in the office parking garage.

[bigchillcar]

Pillow,
What is it about the magnecors that you like? I hear you about the parking. I've got covered parking at home, but with a new position in a new company, I have nowhere but outside to park my daily driver 911!

Ryan

[Jocke]

Hi Ryan!

I had a simular problem on rainy days with my 930, it turn up to be some water dripping on the fusepanel in front, when I opened it I saw that one of the fuel-relay was wet.

Maybe you should check it at least.

/Jocke

[bigchillcar]

Jocke,

Fortunately, I haven't been seeing any water up in the front near the fuses! It's staying bone dry, thank goodness. Thanks for the suggestion, though!
Ryan

[jluetjen]

The solution to your problems is about $1.50 away. Get a tube of "Dielectric (which means non-conductive) Grease" from your local autoparts store. Clean and dry the boots at both ends of your spark plug wires as well as the tops of the plugs themselves. Squirt a dollup (a little less then the volume of toothpaste on the toothbrushes in the toothpaste ads) into each boot and reinstall the wires. This should help prevent moisture from collecting inside the boots and help to prevent the shorts.

[Pillow]

http://www.magnecor.com/

One of the best product websites I have ever seen. Technical but yet they break it down to an understandable level. I love when a company producing a high performacne product actually explains why it is better than a normal product.

I bought a set for my '66 VW and the quality is excellent! The solid spiral core is much nicer than any wire core than I have previously seen (and I have seen a lot of wires, normally cut my own). And this was just the regular 8mm set, not the race 8.5mm or 10mm sets!

There are a few other manufactures of spiral core wires but they go off gimicky ads and flashy BS which is a turn off to me as a buyer... Give it to me straight with reasons why and I will buy it if it makes sense.

When you have a few hours to kill the website is great reading. Nice and plain too, no BS flashing cr@p.

[bigchillcar]

John and Adrian,

Thanks for the great tips! I'll check my pockets for that $1.50!

I'm going right now to check out the magnecor site.



Ryan

[ohecht]

I have used dialectric grease before, but I have never understood how it does not interfere with the spark.

Is it just the overwhelming power of the ignition spark that can overcome the grease?

Olivier