sluggish drive

[devans]

Hi everyone,
For some reason my engine management warning light was coming on when i started the car. Flashed for about ten seconds then went fully on. Car is very sluggish.
To remedy, i removed the battery, charged up as it was flat after leaving for some time. Replaced battery, left for a minute with ignition in the on position, then off for 10 seconds, then turned engine over for 5 minutes. Everything was sorted, no more issues and car has been driving well for the last couple of weeks.
However, during some heavy rain this morning I decided to take the car for a drive and the old issues have returned. Car very sluggish with poor tickover, engine management light flashing for approx 10 seconds, then fully on. Does anyone have any ideas!!
Only job i have had done recently is a replaced variocam solenoid (passengers side). The car is due a service soon. I seem to remember that the last time it had this issue, it also rained hard.
Thanks.

 

[steveoz32]

I'm not familiar with the engine yet, but I've done quite a few repairs on other engines.

If it's happening when wet, it could parhaps be worth checking the MAF?

I've seen them go on quite a few cars, and the most common I have seen is water getting into the intake, getting the filter wet and the moisture killing the maf. Symptoms tend to include cars going into 'limp' mode and not exceeding a certain RPM, and or generally running like a bag of spanners almost as if the engine is missing on a cylinder and has a huge loss in power.

Just a thought.

 

[tscaptain]

ORIGINAL: devans

The car is due a service soon. I seem to remember that the last time it had this issue, it also rained hard.

Coil packs?

 

[devans]

Interesting
Can i test the MAF as i believe it is quite expensive to just replace?

 

[Richard_Hamilton]

ORIGINAL: devans

Interesting
Can i test the MAF as i believe it is quite expensive to just replace?

The only real way to tell is to read the output values with a Porsche tester.

As it happened when it was wet, I would agree with Alan that it is more likely to be a col pack (or packs).

A diagnostic check should tell you what's wrong.

 

[steveoz32]

On a cheap car you could disconnect the plug to the MAF and see if it made any difference to the running, as if it's faulty or sending a dodgy signal it would put the car in a limp mode at the ECU level anyway, if it's disconnected it would have no effect if it is faulty. But I don't think I would recommend it on something more expensive like the porsche motor.

I've had coilpacks go on the Z as well, the obvious sign is the offending coil resulting in there being no firing on that cylinder. The car also sounded more like a subaru! You could tell it was missing by the sound and the power would be down. The only way to tell which coil it was though was to put it on a conzult diagnostic machine, I suspect your looking at a similar thing on this to identify the offending cylinder / piston no coil pack as Richard suggested.

 

[AlexBell]

I've had this a couple of times and it's most probably the coils as mentioned. But you need to connect to a Porsche tester.

But seriously, your first reaction to a CEL is to disconnect the battery? [&:]

 

[devans]

Cheers everyone. I keep promising to get the car serviced. Probability is a coil. Funny though that car is driving ok again as long as it doesnt rain too hard. Hopefully the service will sort things out.