Dear everyone,

Hi, I am a newbie to this board. I really need some help here. Actually I am encountering some problems with my 996tt and am wondering if you guys can help me to find the answers.

Problems:

1. Ticking noise from the dashboard area - The ticking noise is not continuous. The noise from the dashboard area seems to come from some faulty electrical wiring or connections and is not speed related. It seems that if I turn off the A/C, the ticking noise from the dashboard will stop. The ticking noise only happened when the car is warmed up. Someone suggested that the noise may be from a bad A/C drop-out relay or a bad A/C heating fan or auxiliary cooling fan. Do you think this ticking noise may be from a bad cooling or blower fan which is located at the right front of the car (as mentioned in Q2 below, my car may have a faulty cooling fan).

2. Groaning/Moaning noise from the back of the right front wheel - The noise continues even when the car is parked/stationary (with ignition on). The groaning / humming echoing noise is from the back of the right front wheel near the fuel tank area. It creates a humming echoing sound like “Won ... Won ... Won ...”. This noise only appears when the car is warmed up. Someone suggested to me that the noise might be from a faulty fuel pump or cooling fan. Any views?

3. Stalling problem - my car is a Tiptronic (stock without modification). The stalling is most apparent when I was driving at normal speed and then slam on the brakes. Before the engine is warmed up, the car runs fine when I press on the gas paddle, however, once I slam onto the brake, the revs will drop quickly (to below 500) and the engine starts to stumble and wants to stall. It won't happen once the engine is warmed up. Also, if I have the A/C turned off, the situation seems to be better. Someone suggested to me that it may be caused by a vacuum leak. I am wondering whether a faulty MAF or O2 sensor could also cause the engine to stall in these circumstances? I’ve heard that some manual 996 owners have a similar experience when they press on the clutch. Have you guys encountered situation like this before? Do you think it is possible that this stalling problem is caused by a contaminated fuel filter (the car has been in storage for about 3 months without much fuel left in the fuel tank)? Also, howabout the possibility of a faulty cam shaft position sensor or idle stabilizer?

4. Clunking noise at the engine area - Sometimes when I start the engine in the morning, I can hear a pretty loud "clunking noise" from the engine area. Moreover, I have noticed that sometimes there will be some white/grey color smoke coming from the exhaust pipes with the smell of gasoline when I start the car (it only last a couple of seconds). Could there be some sort of leakage? Do you think that this could be the cause of the stalling problem that I've been encountering lately?

5. Loud plastic rubbing noise from the right side of the engine area when I start the engine in the morning - could this noise be from a bad fuel pump (does the 996tt have two fuel pumps - one at front and one in the back)? Howabout a bad alternator or belt tensioner? Any idea as to what that is? It goes away when the car is driven for a couple of mins?

6. Battery - I just have my battery changed. When the radio and A/C is off, the battery level is around 13.5. But when the radio and A/C is on, the battery level drops to around 12. Do you think this is normal?

Best regards,
Superfans.

 

Smoke at startup is pretty normal as the engine is a flat six so a little bit of oil will sit in the head and smoke when you first start the car. Not sure about the other things. Your car should still be under warranty so I would take it to the dealer.

 

Wow! Did you buy the car new or used?? Still under warranty?

I agree with Buddy, the currently TT-less mod-freak....take your car to the dealership, give them a list and leave it there until they solve all the problems. If it is not under warranty, there are some pretty sharp folks on this board with a LOT of knowledge about these cars. I'm sure they would be happy to chime in....HMMM! HMMM!...Fellas!?

 

Number 5,

There is no fuel pump in the rear. Your fuel pump is located up front in the fuel tank. Providing everything is stock. The noise you are hear is your engine belt warming up. Yes, it will go away when warm.

Number 3,

I have experienced the stalling problem you described on a six speed once when using the brakes at low engine speed. There is an adjustment the dealer can make to rectify this.

 

No.1 Ticking noise - some bad electrical connections? There was a TSB in Jul 02 regarding "Interior - R/H Side Instrument Panel Clicking Noise". Does anyone knows the details?

 

Dave,

You live pretty close to PES don't you? Go over there and tell Winslow, Jeremy and Tony to get that motor in my car! I am having some serious Porsche withdrawals here!

 

No2 sounds most likely possible hydralics. check your hardlines fitting hoses for anything out of the ordinary. (pinched lines, kinks etc)

 

Dear all,

No.3 - A little update on the stalling problem. Acutally if I don't turn on the A/C, headlights and radio (with the battery level slightly below 14), then the rpm will only drops a little (still above 500) and stalling will not happen even when braking. Only when I have all the electrical items turned on (especially the A/C - with the battery level drops to slightly above 12), then the problem will appear. I am wondering whether the stalling has anything to do with the possible faulty A/C fan (which draws a lot of electricity from the battery) coz the ticking noise from the instrument panel area seems to be from a faulty A/C fan. Yesterday, when I have the A/C turned on, the ticking noise appeared after the car is warmed up. Once I turned off the A/C, the ticking noise also disappeared. I've tried a couple times (ie turn on and off the A/C) and the same has happened so I guess the ticking noise must be A/C related. Furthermore, I also heard a loud squeaking noise from behind the instrument panel when I turned on the A/C. Any views?

 

As mentioned in point 5 of my first post, there is always a loud plastic rubbing noise from around the centre of the engine when I start the car. It will last for about 5-10 seconds. Do you think this may be the sound of a faulty alternator or bad alternator belt?

If the battery is running low, then will it affect the engine rpm? Is it possible that when applying the brakes, more electricity will be drawn from the battery to operate the vacuum pump, brake booster, etc. which sort of causing the engine to cut-off?

 

where are u located superfans?

on No.1, could it be the CD player in the dash? i heard that many time on our cars.

 

Hi guys,

This problem is giving me a lot of grieve. I am pretty sure that the ticking noise is A/C related. Once the A/C is off the ticking noise will go away.

The problem is that there is no CEL in my case. I am wondering whether the computer can detect a minor vacuum leak. I've heard that one can actually try testing the brake pedal to see if there is a leak. Isn't it that when you step on the brake pedal a couple of times after the engine is off, the brake pedal will become hard due to the release of vacuum in the booster. I've tried that but my brake pedal did not get harden and I can continuously press onto the brake pedal as if the engine is running. Does it mean that there is a vacuum leak in the brake booster?

As to the alternator, it seems that it is still working alright (although the plastic rubbing noise continues for the first 5-10 seconds after start-up). Everytime when I start the engine, the battery level will be around 12V before ignition is on and 14V after ignition is on (of course, with A/C, lights and radio off). Once I turn on the lights, A/C and radio, then the battery level will drop to around 12-12.5V gradually. I am not sure if this is normal.

The frustrating thing is that the dropping of the rpm while braking only happens during the first 5-10 mins drive after start-up. Once the engine is warmed-up, this problem will disappear (at least it won't be as bad which causes the engine to shudder or stall).

 

does A/C ticking happen with fan on but condensor off. It may be failing a/c fan or trash in ducting somewhere. this is common on other vehicles. Had a bad fan in a BMW 740 il and it ticked alot when fan on. A/C or not.

 

I am not sure if there is any difference with the condensor off. I always have it on with the fan. However, this ticking noise doesn't always appear. It only appears when the engine is hot. The noise is the same with a low or high fan speed so I do not think it is a falling object. It sounds more like an electrical ticking noise. It sound like "tick ... tick ... tick (then stop for about 5 seconds and then) tick ... tick ... tick (again)". Do you think this could be a loosen A/C relay? Howabout a faulty A/C fan?

With respect to the rpm surge while braking, I have a feeling that there may be a leaking vacuum brake booster plus a faulty alternator (not to mention that there may be a faulty A/C fan) which cause the rpm surge when the engine is cold (because of the vacuum leakage, more current is drawn by the vacuum pump therefore causing the rpm to drop). Once the engine is warmed up, the leaking may not be as bad (because the rubber tubings have expanded) and thus draw less current from the battery which therefore allow the engine to run a bit smoother even when applying the brakes. Any views?

 

Yesterday, I placed my foot on the brake pedal when starting the engine but the brake pedal did not depress or drop. Does it mean that the brake booster is not functioning properly?