Power lag after carwash - 986 Forum - The Community for Porsche Boxster & Cayman Owners

coolbreeze551 · 08-24-2011, 05:04 PM

I am experiencing slow throttle response and what seems like a decrease in power after my car is washed. I don't wash the engine before I experience this and he only water that might be effecting it is the "under wash" when you drive into the car wash and some hoses automatically spray underneath your car. Is there something located down there that would be effected by short spray of water (about 1 second long or less)? Has anyone else experienced that?

Lil bastard · 08-24-2011, 09:15 PM

This can be dangerous... there have been reported cases of engines which have grenaded by hydrolocking after running through an automatic, or hi-pressure car wash. Seems the water floods the intake after shooting into the side intake vent.

Rare, but it has happened.

I think most people hand wash.

Cheers!

ekam · 08-25-2011, 02:38 AM

Why do you take your car to an auto wash??? It should only be hand washed.

ProjectM96 · 08-25-2011, 05:04 AM

The Spark Plugs might have gotten some water in them.

They are located behind the left side rear tire.

jcb986 · 08-25-2011, 05:39 AM

I would never run my Boxster through a car wash...it's not wise at all. :ah:

DenverSteve · 08-25-2011, 05:58 AM

Quote:

Originally Posted by coolbreeze551

I am experiencing slow throttle response and what seems like a decrease in power after my car is washed. I don't wash the engine before I experience this and he only water that might be effecting it is the "under wash" when you drive into the car wash and some hoses automatically spray underneath your car. Is there something located down there that would be effected by short spray of water (about 1 second long or less)? Has anyone else experienced that?

I can't imagine that there is anything exposed underneath the car. But, even so, I wouldn' t be putting my convertible through a high-pressure anything. It is so small hand washing takes only a few minutes.

Lil bastard · 08-25-2011, 06:22 AM

Quote:

Originally Posted by ProjectM96

The Spark Plugs might have gotten some water in them.

They are located behind the left side rear tire.

Actually, it's a 6-cyl. Boxer engine - you have a bank of 3 cylinders (and 3 plugs) on either side of the car.

Given that it's coil-on-plug, it's unlikely that water can get in the plug tubes.

Cheers!

Lil bastard · 08-25-2011, 06:26 AM

Quote:

Originally Posted by DenverSteve

I can't imagine that there is anything exposed underneath the car...

There may not be much exposed under the car, but you have a pretty gaping hole on either side rear quarter panel - the engine bay cooling fan exhaust on the P-side, and the engine air intake on the D-side (which leads straight to the engine intake).

Cheers!

coolbreeze551 · 08-25-2011, 07:04 AM

Sorry, I guess my original post was unclear. I don't run my car through an auto wash. I hand wash it, however, when I drive into the washing bay there is an option for an under-car spray of water to get spots under the car that you normally can't with hand washing. I do not take my car to an automatic car wash, I always hand wash, just the quick water spray underneath is automatic.

Cheers

lifeisgood · 08-25-2011, 07:17 AM

What happen if you drive in the rain and over a puddle of water?

Keith Newby · 08-25-2011, 07:18 AM

They're cars after all. Wash them how you see fit and don't apologize for the method you choose. Damn!

maj75 · 08-25-2011, 09:50 AM

Washing Bay?

Are you using a high pressure, coin operated wand on the car?

Have you taken the snorkle off the car?

If you got water into the drivers side air intake, the air filter could have gotten wet/damp. Check the air filter and air box to make sure there is no water inside.

Overdrive · 08-25-2011, 11:58 AM

maj75 is pretty much on the same track I was thinking of. It's possible that maybe this underspray is making something unhappy, but unless you never let the car see rain I figure the same thing would happen when driving in rain.

Are you being careful not to spray directly at and into the air intake on the driver's side when you're hosing off the car? Whether you've de-snorkeled the car or not, it's still possible to put a lot of water into the intake box if you're spraying right at it.

Do you leave the car running when you wash it at this place?

stephen wilson · 08-25-2011, 01:09 PM

Even driving rain won't spray high pressure water Directly up.

Steve Tinker · 08-25-2011, 04:11 PM

I'm betting that the OP has at least one coil pack with a cracked surface...
Having a high pressure under chassis water wash or driving at high speed in heavy rain will cause a faulty coil pack(s) to "short" via the water to the chassis instead of firing the plug(s).

Lobo1186 · 08-25-2011, 04:12 PM

I had a similar problem once with a 6cyl mustang. What had happened was the water had gotten into the distributor cap and messed with one of the cylinder's current causing it to miss-fire only under heavy acceleration. It just seemed to be down on power, when in fact it was having no or little ignition.

Now, it could be possible that since we have coilpacks on the boxster that one was fouled by the water or somehow water broke the seal is is messing with a single plug. If it is having a hard time getting a good spark it could miss fire or have a poor ignition.

just my thoughts.