hysteric

Hi all,

My C4 has taken to fair weather driving only and during the wet seems to intermittently loose all power, and seems to happen in specific conditions:

1. moderate to heavy rain
2. motorway driving - so constant 60+ mph for more than 30 min

It does not happen in the dry and even in a deluge will not occur if in normal driving (non-motorway).

Symptom: loss of power under constant throttle position, which means I have to coast to the hard shoulder where it will idle very roughly. After it is switched off for about a minute, the car starts perfectly and no bother until about another 45 minutes under the same conditions where the process will repeat itself.

I am thinking its some kind of sensor that is being shorted or similar in the wet and causing the problem.

Any thoughts please would be appreciated.

Indycam

O2 sensor is a known wet problem .
What O2 sensor do you have and does it have the metal tube / protector around it ?

AOW162435

My '95 993 typically refuses to start if there's even a hint of rain on the horizon...


Andreas

ian89C4

I would check all of your electrical connectors on top of the engine as well as the O2 sensor. Sounds like something is just shorting out, under the heavy rain conditions. If you look inside the female portions of the electrical connectors, they have a little rubber seal inside them to help seal the connections, I would make sure that you have all of those, maybe a little water is getting past one that doesn't have one. Sounds like it should be along those lines.

Good luck!

nekbet

Start with a dry car. Let it idle. Get a hose. Put a light shower over one side of the engine. Any hiccups? Do the other side.

Narrow the problem that way, if Ian's connector-by-connector checking doesnt help. I found a few of the weather-proof connectors had loosened up on mine - they looked connected but were not...

good luck,

Mike

hysteric

Thanks for the advice and responses. I will definitely have a look and post any findings for the greater good.

Cheers.

hysteric

O2 sensor had its day and had some dodgy work done to it in the past. It's getting a nice shiny new Bosch sensor today.

Hopefull that will be the end of that.

BGLeduc

I had the exact symptoms you describe, and a new Porsche O2 sensors solved it. I had a non-Porsche model in place, and based on comments here from Adrian and others, went with the factory part. Problem solved.

Good luck.

Keep in mind that if you do the swap your self, an O2 sensor socket will be VERY handy to have.

Brian