Hi everyone wonder if anyone can help. My brother has a 1999 (AGU engine i think) mk4 golf gti and it does not not start. The engine turns over but will not fire up. I have VAGCOM/VCDS and have run a fault code check but as i am a bit of a noob with VCDS dont realy know how these faults could stop the engine firing up. There is however another problem that concerns me more, when the engine turns over the displays "STOP oil pressure low" and when turning over without the oil cap on it does not throw oil all over my face (which i presume should happen, its happened to me before) could this be becasue the oil pump does not work? Please could someone more enlightened than me have a read through these fault codes and see if there is a potential cause for this none starting issue, it would very much appreciated. Friday,22,October,2010,15:33:16:46862 VCDS Version: Beta 912.0 Data version: 20091201 -------------------------------------------------------------------------------- -------------------------------------------------------------------------------- Chassis Type: 1J - VW Golf/Bora IV Scan: 01 02 03 08 15 16 17 19 22 29 35 36 37 39 46 47 55 56 57 75 76 Mileage: 239160km/148607miles ------------------------------------------------------------------------------- Address 01: Engine Labels: 06A-906-018-AGU.lbl Part No: 06A 906 018 CG Component: 1.8L R4/5VT MOTR HS D02 Coding: 04000 Shop #: WSC 00028 5 Faults Found: 18010 - Power Supply Terminal 30: Voltage too Low P1602 - 35-10 - - - Intermittent 17967 - Throttle Body (J338): Fault in basic settings P1559 - 35-10 - - - Intermittent 16486 - Mass Air Flow Sensor (G70): Signal too Low P0102 - 35-00 - - 16500 - Engine Coolant Temp. Sensor (G62): Implausible Signal P0116 - 35-10 - - - Intermittent 17973 - Throttle Actuator (J338): Lower Stop not Reached P1565 - 35-10 - - - Intermittent Readiness: N/A ------------------------------------------------------------------------------- Address 03: ABS Brakes Labels: 1J0-907-37x-ABS.lbl Part No: 1J0 907 379 Q Component: ABS/EDS 20 IE CAN 0001 Coding: 13504 Shop #: WSC 00028 No fault code found. ------------------------------------------------------------------------------- Address 15: Airbags Labels: 6Q0-909-605-VW5.lbl Part No: 6Q0 909 605 A Component: 02 AIRBAG VW5 0003 Coding: 12338 Shop #: WSC 00028 1 Fault Found: 00532 - Supply Voltage B+ 07-10 - Signal too Low - Intermittent ------------------------------------------------------------------------------- Address 17: Instruments Labels: 1J0-920-xx0-17.lbl Part No: 1J0 920 921 A Component: A4-KOMBIINSTR. VDO V18 Coding: 05442 Shop #: WSC 00035 Part No: IMMO Component: IDENTNR: VWZ7Z0X1802943 IMMO-IDENTNR: VWZ7Z0X1802943 No fault code found. ------------------------------------------------------------------------------- Address 19: CAN Gateway Labels: 6N0-909-901-19.lbl Part No: 6N0 909 901 Component: Gateway K<->CAN 0001 Coding: 00006 Shop #: WSC 00028 No fault code found. ------------------------------------------------------------------------------- Address 46: Central Conv. Labels: 1J0-959-799.lbl Part No: 1J0 959 799 AH Component: 4U Zentral-SG Komf. 0001 Coding: 04096 Shop #: WSC 00028 Part No: 1J2959802C Component: 4U Trsteuerger. FS0002r Part No: 1J2959801D Component: 4U Trsteuerger. BF0002r Part No: 1J4959811C Component: 4U Trsteuerger. HL0002r Part No: 1J4959812C Component: 4U Trsteuerger. HR0002r 4 Faults Found: 00953 - Interior Light Time limit 25-10 - Unknown Switch Condition - Intermittent 01330 - Central Control Module for Central Convenience (J393) 53-10 - Supply Voltage Too Low - Intermittent 01389 - Tailgate Open Switch (F124) 29-10 - Short to Ground - Intermittent 00943 - Heated Exterior Mirror; Driver Side (Z4) 35-00 - - End ---------------------------------------------------------------------
the oil pressure low could well be an issue, id drop the sump and check the pick up is clean for the pump - (these are prone to getting a film of pap on them) then make sure the oils filled up to the proper level. there also seems to be an issue with low voltage...is the battery properly charged, if its notr been run for a while might be worth taking the battery off and giving it a charge up
I would start with the power supply fault first as that is the most likely to be the cause of the non start. When you get it running erase the rest of the codes and see what comes back. First i would be checking if the plugs are getting wet with fuel. Check battery voltage and also battery voltage when cranking, if the battery voltage is dropping too low on cranking then the ecu wont switch on fuel injectors etc. If that checks out ok then check all fuses and then its onto things like ecu relay if it has one, it may be worth getting hold of a wiring diagram for the engine if you can just incase you need to go more indepth with the diagnostics The other codes in the engine can also lead to poor running but i would of thought it should still start The throttle body fault should just hopefully require a clean out and the basic settings reset Coolant sensor will most likely need replacing, its possible that its causing the car to overfuel on startup or not fuel enough
Hi guys thanks for the input. I have fitted a new (light green) coolant sensor, reset the basic settings on the throttle body and cleared the fault codes. I have used a battery off my dads vectra Sri estate, and still doesnt start, modern engines are just terrible to diagnose. Voltage of the batery is just over 12v and when cranking over the voltage drops to between 8-9v, is that too low when cranking? Only fault code on the engine side of things that came up after this was voltage too low. Any other ideas would be much appreciated? Any other guesses would be much appreciated, my next
I find modern cars easy to diagnose IMO. They tell you what's wrong. I would start with the battery. 8-9v won't operate things correctly. Try using jump leads from another running car to keep voltages up.
This sounds like a voltage low problem to me too. The newer motronic ecu's really dont like low voltages. I found this on both my car, and my mums leon cupra. 8 to 9v cranking does sound very low too. Plus you will find a low voltage will trigger all sorts of other codes too. One thing i have found is that jump leads didn't always work when the battery in the car was rather nackered and that it was best to start with an entirely new battery. Had a fault on a couple of leons (basically mk4 golfs) now whereby the fan control relay dies and shorts to ground causing a constant battery drain which kills the battery in short order.
check and clean all earths and 12v terminals the battery may have 12v but it may not be getting to the battery
that was pretty much where i was gonna start next with the earths if i cant think of anything else. Just trying to find where terminal 30 is at the moment, might provide better insight. The voltage when cranking reading was taken from vag com measuring blocks if that makes things more clearer?
Should imagine terminal 30 will be one of the main power supply relays. Is there an ecu relay? It may be worth trying that first before anything else. Are both voltage readings taken from engine measuring blocks or did you measure the battery using a multimeter first? The reason i ask this is because if the engine ecu is seeing 12v but then is only seeing 8v when cranking i would say you have high resistance in the wiring to the engine ecu. The voltages will all check out ok if you check them to the ecu but as soon as any current is drawn the wiring cant cope hence the low voltage reading when cranking.
my multimeter was not working (batery i reckon), so both readings from were viewed on the measuring blocks. I checked the fuel and its getting to the rail. I taken a few of the spark plugs and coil packs out and it doesnt seem to spark, although no fault codes present for coilpacks. Im not too sure about the engine ecu relay, looking on this diagram though it does seem to have one. http://www.vwcaddyforum.com/showthread.php?t=44244 How do you check if the relay is not working, is there a way of testing it?
Right now ive looked at that i have a better understanding of it. Terminal 30 is battery voltage so as you have said firstly clean up the connections of the earth and positive terminals at both ends and check they are tight (obviously disconnect them from the battery first!) Check the maxi fuses on top of the battery if you havnt already. (the big metal ones) I would also check fuses f28 (15amp) and f43 (10amp) The engine ecu relay is K46 which works off a switched earth, pop the relay out and terminal 17 of the holder should see battery voltage if you probe it, terminal 17 should see 12v with the ignition on. If these both check out ok then you can try my next suggestion at your own risk Bridge pins 17 and 20 and see if it starts, if it does your relay is at fault
This can all be caused by a faulty battery as i said before. I know you said you tried another battery, but this could be fine to start another car but not have enough for the ecu to like. Terminal 30 is as mentioned battery voltage. The ECU only sees this on one wire (presuming it is the same as the later me7.5 ecu's which is likely). The coilpacks will not spark if this voltage is too low, there is a relay which takes the same switched live as the ecu, this allows the ecu to turn on and off the coils, if the battery voltage is too low, this does not happen. When i first did my mk2 20v swap, the battery was very flat having been sitting for 2 months and the car did not start at first, and i got the terminal 30 voltage low fault. I changed the battery and it started fine and ran, drove the car for a short while and then it spluttered and died, giving the same terminal 30 fault and a host of others. This was traced to the alternator not charging. I would start by checking the battery and making sure you have at least 12.6v there with the engine not running. Cranking voltages as low as 8 or 9, i would not expect to be high enough. You can check by finding the 2 relays in the scuttle which control the ecu and secondary air injection (not sure if this is on AGU engines), if this is clicking on and staying when you start it then all is well, if it is not, or is clicking on and off then that is a sign of not enough voltage. As said by others I would also check the big fuses on top of the battery as vibrations can often cause hairline cracks in these.
Update: Right I have been informed off my brother that the ecu relay clicks when ignition on and clicks when turned off. It's now got a new battery on it, everything on the top of the battery looks fine, and the fuses look fine. But, still doesn't start. On rosstech website the terminal 30 fault could be indicative of an alternator fault, could that stop it starting ( I don't think it would, but ya never know) and the short to ground fault on the tailgate open switch, is this possibly a cause for the none start? Also could it be an imbiliser or ecu fault?
If there was an alternator fault then it should still start providing the battery is charged, the tailgate open switch will have nothing to do with the non start either. If it was an immobiliser fault the car will start for a second or two and then cut out. It could be an ecu fault but as it has been said many a time on this thread if the ecu is not recieving a certain voltage it will not power up things it needs for the car to run such as the coil or fuel injectors. Have you tried bridging the relay like i mentioned a couple of posts above? The relay may click but if its burnt out inside it may not make a proper contact.
No haven't done the bridging, it's my bro who's car it is so I'm relaying the advice on to him. Not sure whether he's tried bridging the relay yet but I've told to definitely try it. Im still thinking its this to be honest. Ecu relay, just to make sure, is it on the back of the fuse box or in the scuttle panel area as suggested above? Cheers guys by the way.
