question about a tining belt service

[xx_s4quattro_xx]

Hi i guys i was wondering what is the symptom of a bad timing belt because i picked up my car about 2 month ago with 120k and i ask the dealer if the previous owner had a timing belt change and he sed he dont know so do you guys know what the symptom to a bad timing belt is? Let me know thanks oh the car is a 2000 audi s4.

[ThePaintballGuy]

If it made it that long it most likely has had it replaced. They mostly will not go more than 80-90K miles.

And there are not any symptoms that I know of. It just breaks and then you get to rebuild the engine.

Josh

[mholme]

Most of the belts I've done have all looked fine when removed, even at higher mileage, but they are most likely weakend internally. Make sure the rollers and waterpump are also replaced, so get a complete kit if you are doing it yourself.

[xx_s4quattro_xx]

thanks i think im going to change it again to be on the safe side i was just wondering what kind of symptom there was because my car is throwing code p1557 Charge Pressure Control: Positive Deviation any idea what that is? The search button didnt really help me.

[mholme]

You have a boost leak somewhere. You need to pressure test.

[The_Jerbel]

That code means that your wastegates most likely aren't functioning properly. Your car is boosting higher than the ECU is requesting. The cause is probably either a bad N75 valve, bad WG lines, or a WG that isn't opening like it should.

[xx_s4quattro_xx]

oh thanks because i was trying alot to find out what that was.

[ThePaintballGuy]

Hopefully it's not a bad wastegate... that would suck.

Josh

[mholme]

Or a wastegate line..that would suck..But wouldn't he be seeing "charge pressure exceeded" codes?

[titleiststud]

Odds are it's a boost leak. I had an intercooler hose off and was throwing the same code. Do you have any symptoms or is it just throwing the code?

[The_Jerbel]

Or a wastegate line..that would suck..But wouldn't he be seeing "charge pressure exceeded" codes?

He did, the actual code looks like this:
p1557 Charge Pressure Control: Positive Deviation

That means that the boost pressure is positively deviating from what the ECU is requesting. A negative deviation code usually means that there is a boost leak somewhere.

I would pressure test just to be safe, but I'm betting that it's a bum N75 or associated lines.

[mholme]

O I C..I was talkin about 17963 - Charge Pressure: Maximum Limit Exceeded. I thought that one was the one more commonly associated with wastegate/N75 issues.

[xx_s4quattro_xx]

ok i will fet pressure test and let you guys know the results and my symptoms are when im sitting at the light sometime the rpm would be jumping up and down like its gonna stall out. What if it is a waste gate what would i have to do to fix the problem?

[Jsmooth65]

If it made it that long it most likely has had it replaced. They mostly will not go more than 80-90K miles.

And there are not any symptoms that I know of. It just breaks and then you get to rebuild the engine.

Josh

I did the first TB job for my car at 101k miles. Belt looked great still. So your statement is not exactly true.

[The_Jerbel]

ok i will fet pressure test and let you guys know the results and my symptoms are when im sitting at the light sometime the rpm would be jumping up and down like its gonna stall out. What if it is a waste gate what would i have to do to fix the problem?

It would be easier to diagnose the problem if I had some logs.

It sounds like it could be a boost leak, like a leaky WG line or something.

If it's a bad WG you'd have to pull the turbo. Cross that bridge when/if you come to it.

[The_Jerbel]

I did the first TB job for my car at 101k miles. Belt looked great still. So your statement is not exactly true.

You can't judge the condition of the TB just by looking at it. Sometimes it gets weakened over time even if it looks good. All of a sudden a couple of teeth strip off and there go your valves.

[xx_s4quattro_xx]

ok here is a vag copy i thought a timing belt change would help but i guess not im still going to get that done but check this out any ideas Address 01: Engine
Part No: 8D0 907 551 A
Component: 2.7l V6/5VT G 0003
Coding: 06611
Shop #: WSC 06325

2 Faults Found:
16487 - Mass Air Flow Sensor (G70): Signal too High
P0103 - 35-10 - - - Intermittent
17965 - Charge Pressure Control: Positive Deviation
P1557 - 35-10 - - - Intermittent
Readiness: 0000 0000

-------------------------------------------------------------------------------
Address 03: ABS Brakes
Part No: 8E0 614 111 A
Component: ABS/EDS 5.3 QUATTRO D10

No fault code found.

-------------------------------------------------------------------------------
Address 08: Auto HVAC
Part No: 8D0 820 043 P
Component: A4 KLIMAAUTOMAT D56
Coding: 00160
Shop #: WSC 06325

No fault code found.

-------------------------------------------------------------------------------
Skipping Address 15-Airbags

-------------------------------------------------------------------------------
Address 17: Instruments
Part No: 8D0 920 980 DX
Component: B5-KOMBIINSTR. VDO D13
Coding: 02264
Shop #: WSC 22197

2 Faults Found:
00849 - S-contact at Ignition/Starter Switch (D)
31-10 - Open or Short to Ground -
Intermittent
01311 - Information Data Bus
37-10 - Faulty - Intermittent

-------------------------------------------------------------------------------
Address 35: Centr. Locks
Part No: 8L0 862 257 N
Component: CV-Pump D11
Coding: 16232
Shop #: WSC 06325

4 Faults Found:
01367 - Central Locking Pump Run Time Exceeded (Likely
Leak)
35-00 - -
01370 - Alarm triggered by Interior Monitoring
35-00 - -
00991 - Interior Lights
28-00 - Short to Plus
00956 - Key 2
09-00 - Adaptation Limit Surpassed

-------------------------------------------------------------------------------
Address 37: Navigation
Part No: 4B0 919 887 A
Component: Navigation 0001

1 Fault Found:
65535 - Internal Control Module Memory Error
00-00 - -

-------------------------------------------------------------------------------
Address 45: Inter. Monitor
Part No: 4B0 951 173
Component: Innenraumueberw. D03
Coding: 00101
Shop #: WSC 06325

1 Fault Found:
01380 - Alarm triggered by Anti-Theft Sensor; Rear
Left
35-00 - -

-------------------------------------------------------------------------------
Address 55: Xenon Range
Part No: 4B0 907 357
Component: LEUCHTWEITEREGLER D003
Coding: 00012
Shop #: WSC 06325

No fault code found.

-------------------------------------------------------------------------------
Address 56: Radio
Part No: 8D0 035 195 A
Component: Radio D00
Coding: 00115
Shop #: WSC 06325

1 Fault Found:
65535 - Internal Control Module Memory Error
00-00 - -

End

[sCeRaXn]

I dont know that much about these cars yet, but from what ive read Jerbel is most likely correct. As far as the Tb is concerned...there usually arent any symptoms before it goes. Sometimes the belts look brand new(not even a tooth missing) even after theyve skipped teeth and destroyed an engine. Most of the time theyll just stretch under high tension and cause the damage. The best way to fight this is to put a new one on.

Good luck with fixing the codes.

[The_Jerbel]

Looks like the MAF sensor might also be toasty. The ignition switch as well.

Clear all codes and see which ones come back. It's obvious you haven't cleared codes in a while...

[xx_s4quattro_xx]

the maf sensor is like 2 month old and i have a turbo timer hooked would that be messing with the ignition switch?

[The_Jerbel]

Well the MAF code is probably old then.

The turbo timer could possibly throwing the code for the ignition switch.

I would just clear all the codes and see what comes up in the next few days.

[xx_s4quattro_xx]

thanks jerbel ill get this pressure test i setup a appointment with jeff moss from torque factory he sound like a good guy. How much does a n75 valve run for? and is it hard to install i think im just gonna change that too.

[The_Jerbel]

It's like $85. Changing it is a good idea.