Hello all. My first post. Here's the background:
Just bought this 1999 A4 Quattro last month. My first Audi. The car is acting strangely. I had the battery tested (after it wouldn't start the car on a few occasions) and it failed a load test so I swapped in an old spare battery I had. It was fine for 2 weeks, but yesterday it wouldn't start. The lights were very weak, but there was still a bit of power. I saw nothing left on that could have accounted for a battery drain. I got a boost and it stalled right away unless I revved high (3000 - 4000 RPM). I figured the battery couldn't hold a charge at all anymore so I bought a new one. It starts the car, but still needed high revs for several minutes before it won't just stall. But now, when holding the accelerator steady, the engine pulses (as if I was slowly pumping the gas). It isn't drivable and stalls easily. I wonder if the computer needs some kind of calibration or reset. Maybe the owner's manual says a way to do it, but I don't have it. I also wonder if there may be a short that was draining the battery (have left it disconnected). Any tips will be very much appreciated.

 

have you checked your alternator?

 

Is there an easy way to check the alternator? I do have a multitester.
But isn't there some reset procedure to follow after replacing the battery, which failing to do could account for the odd behavior?
Tnx

 

When i disconnected my battery to install my deck the only thing i had to do was put in the code for my deck, i have a newer audi.
Things to look for:
Stereo Turns off
RPM gauge drops down low or all the way to zero while driving or idling
Electronics in the car turn off
Clicking noise when you turn the key
The car wont start and jumping it doesn't work

As far as i know there's no reset procedure But take some steel wool and clean your battery terminals and the connectors. but it sounds like the alternator. it's probrably dead or just about to die. you can connect the multitester to it and see what it's cranking but your car should have a charge meter in the console. Check it out.

 

Thanks again.
Maybe it is the alternator.
Yes, I have had to enter the deck code to get radio going again several times in last few weeks. The RPM guage seemed to work normally until the second battery died a couple days ago. Everything in the car seemed normal except the brake alarm has been going on & off for a few weeks [the pads looks thick enough from the what I can see thru the rims, so I suspect that is unrelated to the current problem and just a bad sensor]. If there really is no magic reset procedure (I vaguely remember something oin the owners's manual before I lost it!) then I guess I gotta take it in to a dealer and will probably get slammed/scammed!
Does anyone have a 1999 (or thereabouts) Audi A4 owners manual that can check for reset procedures (following battery disconnect) for me?!
I'm tempted to get a vag-com diagnostic device but they seem over-priced and I don't have time to get one and figure it all out. I wonder if there is any other way to get error codes.

 

I red somewhere that ur supposed to leave the key in longer, and the windows might not work properly till they all have been put down and up, or something like that. if your in toronto i know a decent mechanic.

 

Hey man usually when you need to rev to higher rpm's it is to reach equalibrium where the batterry charge and output voltage from the alternator are equal to maintain the power. The test for an alternator if you take it off and take it canadian tire they can run it for free, I am not even sure if you do have to take it off. It defenetly sounds like the alternator. I would check into that first as for the stalling could be a result of the alternator or bad coil packs. Once again when you check the alternator you will know the answer. As for the vag-com it saves you a ton of money in the long run there are guys selling them on the forums usually around the $200 mark if you clear all fault codes that warning brake light might go away. my advice is get a vag-com 2-3 diagnostic tests at the dealer will pay off the vag-com.

 

Had this problem with another car and it was the alternator. I was getting that odd revving issue as well. I would also cause injectors to stick (not enough power to inject). I'd find someone to replace it, perhaps you can find someone other than an Audi dealer that specializes in Audi's.

 

check to see if it's your alternator... sounds like it is...

there is no "break in procedure for the battery that I know of...

 

Thanks to all for your input.

UPDATE:
I took the car to Audi Downtown Toronto (164 Avenue Road, Toronto). They looked at it on Saturday and service advisor Jason said that the throttle valve was full of carbon (soot) and that they also needed to clean the fuel injectors and then run engine diagnostics. Jason also said that the brake warning was because of a faulty ABS module (which costs $650 plus $360 labor to replace). I told him to forget the brakes (they work the old-fashioned way without the ABS system) but to do the rest. Today Jason called and said that the car was running ok, but I should also have all the front suspension arms and right-rear sway bar links replaced (there are 4 suspension arms per wheel, and one of the upper ones was replaced during the safety inspection 2 months ago). [Jason said that work would cost about $440 plus about $2000 parts.] He also said that the front brakes flex hoses were cracked and should be replaced. Given that the safety was done recently, I think he was exaggerating the severity of the wear in the arms, links & hoses, although the other advisor insisted that the safety should have revealed these worn components. [The invoice only mentions 4 of the 8 suspension arms, so that suggests that Jason was indeed probably fishing for an excessive repair.] I'm relieved that there is no need to replace the alternator or do any transmission work, so the $573 bill for what they did (includes $115 to diagnose brakes, $115 to clean soot, $115 to clean injectors, $115 to scan engine, plus solvents and tax) doesn't bother me too much, although it was, of course, over-priced.

The engine scan revealed these errors in memory:

Motronic fuel inj. system: throttle position control; power supply (B+) termminal 30 Low Voltage
Climate control: ignition time period signal off (incorrect signal, sporadic);
Central locking: key 1 adaptation limit exceeded; short circuit to B+; open via crash signal; alarm via luggage compartment switch; alarm via inetrior scanning; alarm via door contact switch drivers side; alarm via door contact switch pass. side; alarm via terminal 15

[oddly there was no ABS/brake error listed]

Maybe several of these could have resulted from the recent battery problems. The service advisor wasn't there when I went for the car so I'll ask him tomorrow about the short circuit error, etc.

About the surging throttle issue:
I guess that the guy who did the safety couldn't have know about soot in the throttle valve. I wonder if I got dirty gas on my last tank-up, which was at a small, kinda seedy garage at Courcelette and Kingston Rd (the receipt does show "Premium gas" though).

About the electrical problems:
I have been careful not to leave anything on in the car so I guess the first battery was just old. The spare I put in was not new either, so I assume that I must have left something on that drained it, unless there really is a short somewhere. The 2nd battery might even still be ok -- I will get it tested. I have the new one in now in any case.

I'm tempeted to start hunting for a vag-com. Maybe I could turn off the brakes warning with that (it blinks constantly and beeps 3-times every 20 minutes or so). Any leads would be appreciated!

When I got the key back from the dealer today, the remote didn't work. I assume they dropped it but when I complained Chris Z. said it would cost $225 to replace! I think I'll pass on that too. Chris also refused to give me the first name of the guy that worked on the car. Can't say i recommend Audi Downtown Toronto....