JohnelP

Hi, I wrote about my problem of morning (usually humid) startup trembling for a few minutes until it heats up, MIL lamps blinks and stayed on. It does not happen all the time, but only in humid mornings. If I keep my car in the garage it is OK.

Yesterday I got the Vag tool and I recorded the following failures (1.8 T AEB):
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P0300 Random/Multiple Cylinder Misfire Detected - Intermittent
P0301 Cylinder 1 Misfire Detected - Intermittent
P0302 Cylinder 2 Misfire Detected - Intermittent
P0303 Cylinder 3 Misfire Detected - Intermittent
P0304 Cylinder 4 Misfire Detected - Intermittent

For the readiness test everything passed

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I checked the spark plugs and all look normal (visually) (there is no one black, or oily or sothing). I understood from the previous owner the amplifier (in fact MUX) that drives the coils was changed few thousand miles ago.

I remember once seing a post with a VW passat, that had an intermitent starting problem, and VAG showed him something random related to all the injectors, and since all injectors have the common ground at the fuel pump relay connection, he just changed the fuel relay pump and everything was working OK.

Do you believe it applies to me as well?



Below I copy pasted the VAG results:


Wednesday, 23 November 2005, 20:55:30

VAG-COM Version: Release 409.1-US
Control Module Part Number: 8D0 907 557 N
Component and/or Version: 1.8L R4/5VT MOTR HS D05
Software Coding: 06001
Work Shop Code: WSC 06325

11 Faults Found:
18010 - Power Supply Terminal 30: Voltage too Low
P1602 - 35-10 - - - Intermittent

16684 - Shareware Version. To Decode all DTCs
P0300 - 35-10 - Please Register/Activate - Intermittent

17967 - Shareware Version. To Decode all DTCs
P1559 - 35-10 - PleaseRegister/Activate - Intermittent

16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 35-10 - - - Intermittent

16686 - Shareware Version. To Decode all DTCs
P0302 - 35-10 - Please egister/Activate - Intermittent

16687 - Shareware Version. To Decode all DTCs
P0303 - 35-10 - Please Register/Activate - Intermittent

16687 - Cylinder 3 Misfire Detected
P0303 - 35-10 - - - Intermittent

16688 - Shareware Version. To Decode all DTCs
P0304 - 35-10 - Please Register/Activate - Intermittent

16688 - Shareware Version. To Decode all DTCs
P0304 - 35-10 - Please Register/Activate - Intermittent

16685 - Cylinder 1 Misfire Detected
P0301 - 35-10 - - - Intermittent

16685 - Shareware Version. To Decode all DTCs
P0301 - 35-10 - Please Register/Activate - Intermittent

-------------------------------------------------

I have the Audy Bentley anual, so i could get the codes from there:

SAE- DTC DTC text Corrective action

P0300 Random/Multiple Cylinder Misfire Detected
- Check fuel injectors (Cylinder 1 Fuel Injector -N30- to Cylinder 4 Fuel Injector -N33-) Page 24-87
- Check spark plugs Page 28-17
- Check ignition coils with power output stage Page 28-22

P0301 Cylinder 1 Misfire Detected
P0302 Cylinder 2 Misfire Detected
P0303 Cylinder 3 Misfire Detected
P0304 Cylinder 4 Misfire Detected

Joey T

Do you know when they were last changed? If not, simply replace them. It is cheap.

JohnelP

yes, I took the plugs out, but, since I did not have the check of the plugs in mind, I did not have them bought. I know they are cheap, but simply I did not have a new set with me.

But anyhow, the plugs were OK, and electrodes distance was OK.

Do you think all the cylinders can misire because of the plugs? How the humid weather can affect the plugs?

Allroady DungBeetle

If it where the ignition amp chances are it would only be one or maaaaybe two missing. (not always though see below) Good chance you have a injector/wiring problem. Just go around and check all the wires/connections to fuel injectors and pump etc. Ground trouble is most likely if that *is* the problem.

It could be the ground to the ignition amp, or the "hot" connector on it as well. Don't rule that out as an option. Pull it off and test it. Search for the test procedure here on AW....<ul><li><a href="https://forums.audiworld.com/a4/msgs/1594531.phtml">ign amp test--fun project!</a></li></ul>

4Driver4

What grade oil are you running? What engine is this?