VW Polo 1.4 BKY engine cranks but won’t start

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hooolagon
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Posts: 8
Joined: Sat Dec 24, 2022 1:45 am
Drives: VW 1.4 BKY
Location: UK

VW Polo 1.4 BKY engine cranks but won’t start

Post by hooolagon »

Hi,

I have a 1.4L Petrol BKY engine polo it’s a 54 plate. I bought it as a non runner… previously the owner tried to do a water pump and the car refused to start thereafter… the timing was off and I corrected this making sure to turn the engine over twice and checking the timing marks and tensioner marks. I double checked this using the TDC method also, I used drill bits in holes 8mm and 8.5mm at the top and reassembled everything, I saw online the outer crank pulley for the serpentine belt apparently has a notch and this is the only thing I didn’t abide to but as far as I can tell the pulley isn’t made to measure cam crank correlation.

Previous codes on the car were:
Engine -
17834 - EVAP Purge Valve (N80)
P1426 - 35-10 - Open Circuit - Intermittent
17760 - Bank1; Camshaft Adjustment
P1352 - 35-10 - Setpoint Not Reached - Intermittent
17760 - Bank1; Camshaft Adjustment
P1352 - 35-10 - Setpoint Not Reached - Intermittent
17760 - Bank1; Camshaft Adjustment
P1352 - 35-10 - Setpoint Not Reached - Intermittent

I cleared this, then I tried starting the car once for about 10 seconds but to no avail… other codes are below…

ABS Brakes - 03
01314 - Engine Control Module
013 - Check DTC Memory - Intermittent
Freeze Frame
Fault Status• 00101101
Fault Priority: 2
Fault Frequency: 1
Reset counter: 13
Mileage: 165259 km
Time Indication: 0
18256 - Please check DTC Memory of Engine Controller
P1848 - 000 - - Intermittent
Freeze frame
Fault Status: 00100000
Fault Priority: 2
Fault Frequencv: 1
Reset counter: 13
Mileage: 165259 km
Time Indication: 0

Auto HVAC - 08
4 Faults Found
00819 - High Pressure Sensor (G65)
07-10 - Signal too Low - Intermittent
00816 - Power Steering Sensor (G250)
31-10 - Open or Short to Ground - Intermittent
00816 - Power Steering Sensor (G250)
06-10 - Signal too High - Intermittent
01312 - Powertrain Data Bus
79-00 - Please Check Fault Codes

Central Electronics - 09
1 Fault Found.
01598 - Drive batter Voltade
07-00 - Signal too Low

Airbags - 15
1 Fault Found
00532 - Supply Voltage B+
07-10 - Signal too Low - Intermittent

I left the dead battery in the car and used 1.5cm thick jump cables with a 100A battery (known good)

I changed the spark plugs, I checked timing again, I couldn’t do a compression test as my tester is broken, I removed cylinder 1s coil pack and put the spark plug into it (old and new) and placed it against the engine bracket near the timing to ground it and tried starting the car with the fuel pump fuse removed and didn’t see any spark (kinda wondering if that also stops power to the ECU and that’s why I didn’t see a spark both times) but otherwise I’m kind of stumped until I examine further… hoping someone else has something I can look into

I checked all the fuses one by one, the ones by the battery, there’s fuel at the rail, I jumped the power steering fuse with a 6 gauge 3 core housing wire… as the fuse was burnt out/sheared, I checked the ignition relay (taking apart the plastic and making sure I can see it making contact, I’ve yet to test using a multimeter at the coil packs but I’ve not really done that kind of test before and I’m not sure if I can check for ohms on this type of engine (I read someone checking the resistance somewhere)…

Anyway, I usually fix BMWs and last time I tinkered with a VW it was a MK5 golf…

Any info or advice would be appreciated, including any tests I can do using the multimeter at the coil packs otherwise all I intend to do is check for voltage on the connector with ignition on…

Thanks in advance,
hooolagon
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Posts: 8
Joined: Sat Dec 24, 2022 1:45 am
Drives: VW 1.4 BKY
Location: UK

Re: VW Polo 1.4 BKY engine cranks but won’t start

Post by hooolagon »

I haven’t managed to investigate further yet, but I found this online from Crasher but I have no idea why this may be the case…

“If you have operated the coil packs out of their position in fresh air, for each coil pack you did this to you have a dead coil pack...” this was from 2017

Thanks,
hooolagon
New
Posts: 8
Joined: Sat Dec 24, 2022 1:45 am
Drives: VW 1.4 BKY
Location: UK

Re: VW Polo 1.4 BKY engine cranks but won’t start

Post by hooolagon »

I did some checks using VCDS and I also did a few voltage tests But I only checked the connector at cylinder 2 and I haven’t checked anything on the actual coil itself…

Intake manifold pressure reads 999.6mbar
Engine speed sensor works
Coolant temp says 8 degrees c
Intake air temperature is 12 degrees c
Ignition timing angle 0 degrees and 3 degrees after cranking
Rpm sensor works on measuring block 11
22/23 shows no ignition delay
26 shows 4.98v across all 4 blocks
Exhaust gas temp block 34-2 36 degrees c
Block 55-2 idle regulator -41.0nM spec -10..0.0% returned to 0 after cranking and -39.0nM after cranking again
+38.0nM after cranking again
Measuring blocks 90-98 displayed no values

Fuel level has increased by itself that’s one thing I’ve noticed, 1/4 tank to just shy of a half tank and then I topped it up with fresh fuel so it’s somewhere above the halfway mark

I only checked cylinder 2, with ignition on; on the plug between the second pin (pin 2) and the last pin (ground/brown wire) I had 12v I’m not sure how to check the coil pack… I feel like I checked all the pins and they displayed 12v keeping the positive probe at pin 2 but unsure how conclusive that is of anything

Still stumped but I’m waiting for a new compression tester and I’ll go from there, if it’s a head gasket I guess I’ll know soon enough, but I’m curious if the camshaft sprockets are keyed onto the camshafts and if they could be out of line, it’s a BKY engine… at this stage I’m not sure if it could still be an ignition switch
littlepolo
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Posts: 778
Joined: Thu Jul 21, 2011 9:47 pm

Re: VW Polo 1.4 BKY engine cranks but won’t start

Post by littlepolo »

I was going to suggest a compression test and it looks like you are planning to do that. A good old fashioned vacuum gauge can be useful for diagnostics.
CarbonChaos
Silver Member
Posts: 404
Joined: Mon Sep 03, 2018 9:43 pm
Drives: 2015 6C GTI DSG Oryx white 3 door.
Location: South west uk

Re: VW Polo 1.4 BKY engine cranks but won’t start

Post by CarbonChaos »

On this engine I’m pretty sure the camshafts and sprockets DO have a keyway, so as you previously stated someone else has ‘tried’ to do a water pump and failed,putting the timing out it’s best to remove the belt and pulleys to check seeing as you have crank -cam correlation faults present.
hooolagon
New
Posts: 8
Joined: Sat Dec 24, 2022 1:45 am
Drives: VW 1.4 BKY
Location: UK

Re: VW Polo 1.4 BKY engine cranks but won’t start

Post by hooolagon »

Thanks for the responses, today I checked the fuel pressure as I have a tester laying around, I measured 2.75bar/40psi at the rail… I’m still waiting for a new compression tester…

I’m intrigued to test the coil packs from this car into a known running VW golf, they use the same coil packs… so when I get a chance I’ll post an update

I’m not sure if I mentioned but the first thing I did when I got the car was check timing; which was off by a tooth at the crank sprocket, I then removed the belt and both tensioners and realigned everything, I used two 8mm drill bits in place of a specific timing tool, after retiming the engine I checked multiple times and it’s still correct when at TDC the drill bits fit snug inside the sprocket through to the actual recessed hole in the engine itself.

I disconnected a connector on a vacuum line above the driver side (UK) engine mount, and what I believe to be the MAP sensor on the intake… and code scanned the car upon reconnecting these connectors I also received a few short to ground errors, maybe because it was wet outside, I’ll post the VCDS logs soon as I get hold of my laptop
hooolagon
New
Posts: 8
Joined: Sat Dec 24, 2022 1:45 am
Drives: VW 1.4 BKY
Location: UK

Re: VW Polo 1.4 BKY engine cranks but won’t start

Post by hooolagon »

I did four scans in total: between cranking, checking VCDS live data blocks, and disconnecting both of those connectors - (I don't know the theory behind why I tried to disconnect those connectors). Something to note, I was cranking the engine for 7-10 seconds at a time, and when I got annoyed I cranked it for like 30 seconds - 60 seconds using clear flood mode (full throttle from inception) at which point the extended cranks gave me a low oil pressure warning sign, nearer the end I noticed the battery light whilst cranking wasn't illuminated when the voltage fell below 11.4v~

I did this all using a 100A battery and thick jump cables, with the dead battery in-situ (connected)... I found a video online where someone had a similar no spark condition and from the video it seemed like the person checked several places using the multimeter and had several wires below the bulkhead or under the drivers side which were shorted, unfortunately I don't speak the language so wasn't able to identify how, what or why but I'm not sure if I can post the youtube link here... I'll risk it in a separate post on this thread in a few days as I do feel the video was fairly insightful... Just wanted to confirm the power steering fuse amperage is 50A? I jumped this with wiring out of a three core for a UK home, not sure if this is feasible - and definitely not a viable long term solution - I'm aware but also curious whether its providing sufficient amperage... pretty sure it may be an issue also provided its not solely for power steering...

Anyway, queue 4 scans:

First Scan:

Address 01: Engine Labels: 036-906-034-APE.lbl
Part No: 036 906 034 GQ
Component: MARELLI 4TV 6280
Coding: 00071
Shop #: WSC 00094
VCID: 67DC8300056DD57E30-4B00
VWZ7Z0D9871964

No fault code found.
Readiness: 1110 0101

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 6R0-907-37x-ABS80.clb
Part No SW: 6Q0 907 379 AA HW: 6Q0 907 379 AA
Component: ABS 8.0 front H03 0001
Revision: 00000000 Serial number: 00000000000000
Coding: 0000005
Shop #: WSC 00788 785 00200
VCID: 7CF6CC6C3CEB66A6CD-513C

2 Faults Found:
01314 - Engine Control Module
013 - Check DTC Memory - Intermittent
18256 - Please check DTC Memory of Engine Controller
P1848 - 000 - - Intermittent

-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: 6Q0-820-045.lbl
Part No: 6Q0 820 045
Component: Klimaanlage X0840
VCID: 6ADAFA34167FE8162F-515A

3 Faults Found:
00819 - High Pressure Sensor (G65)
07-10 - Signal too Low - Intermittent
00816 - Power Steering Sensor (G250)
31-10 - Open or Short to Ground - Intermittent
00816 - Power Steering Sensor (G250)
06-10 - Signal too High - Intermittent

-------------------------------------------------------------------------------
Address 09: Cent. Elect. Labels:. 6Qx-937-049-C.lbl
Part No: 6Q1 937 049 D
Component: 0000 BN-SG. 1S34
Coding: 25790
Shop #: WSC 00788
VCID: 3C760C6C2C6BA6A68D-515A

1 Fault Found:
01598 - Drive Battery Voltage
07-10 - Signal too Low - Intermittent

-------------------------------------------------------------------------------
Address 15: Airbags Labels: 6Q0-909-605-VW5.lbl
Part No: 1C0 909 605 K
Component: 16 AIRBAG VW51 0N 0008
Coding: 12598
Shop #: WSC 00788
VCID: 2C563C2CDC0B36261D-515A

1 Fault Found:
00532 - Supply Voltage B+
07-10 - Signal too Low - Intermittent






Second Scan:

Address 03: ABS Brakes Labels: 6R0-907-37x-ABS80.clb
Part No SW: 6Q0 907 379 AA HW: 6Q0 907 379 AA
Component: ABS 8.0 front H03 0001
Revision: 00000000 Serial number: 00000000000000
Coding: 0000005
Shop #: WSC 00788 785 00200
VCID: 7CF6CC6C3CEB66A6CD-515A

2 Faults Found:
01314 - Engine Control Module
013 - Check DTC Memory - Intermittent
18256 - Please check DTC Memory of Engine Controller
P1848 - 000 - - Intermittent

-------------------------------------------------------------------------------
Address 08: Auto HVAC Labels: 6Q0-820-045.lbl
Part No: 6Q0 820 045
Component: Klimaanlage X0840
VCID: 6ADAFA34167FE8162F-513C

1 Fault Found:
01317 - Control Module in Instrument Cluster (J285)
79-00 - Please Check Fault Codes






Third Scan:

Address 01: Engine Labels: 036-906-034-APE.lbl
Part No: 036 906 034 GQ
Component: MARELLI 4TV 6280
Coding: 00071
Shop #: WSC 00094
VCID: 67DC8300056DD57E30-4B18
VWZ7Z0D9871964

4 Faults Found:
17564 - Manifold Pressure Sensor (G71)
P1156 - 35-10 - Open/Short to Ground - Intermittent
17824 - EGR Valve (N18)
P1416 - 35-00 - Mapped Regulation Range Exceeded
16496 - Intake Air Temp. Sensor (G42)
P0112 - 35-10 - Signal too Low - Intermittent
17760 - Bank1; Camshaft Adjustment
P1352 - 35-00 - Setpoint Not Reached
Readiness: 1110 0101

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 6R0-907-37x-ABS80.clb
Part No SW: 6Q0 907 379 AA HW: 6Q0 907 379 AA
Component: ABS 8.0 front H03 0001
Revision: 00000000 Serial number: 00000000000000
Coding: 0000005
Shop #: WSC 00788 785 00200
VCID: 7CF6CC6C3CEB66A6CD-515A

2 Faults Found:
01314 - Engine Control Module
013 - Check DTC Memory
18256 - Please check DTC Memory of Engine Controller
P1848 - 000 -

-------------------------------------------------------------------------------
Address 15: Airbags Labels: 6Q0-909-605-VW5.lbl
Part No: 1C0 909 605 K
Component: 16 AIRBAG VW51 0N 0008
Coding: 12598
Shop #: WSC 00788
VCID: 2C563C2CDC0B36261D-515A

1 Fault Found:
00532 - Supply Voltage B+
07-10 - Signal too Low - Intermittent






Fourth Scan:

Address 01: Engine Labels: 036-906-034-APE.lbl
Part No: 036 906 034 GQ
Component: MARELLI 4TV 6280
Coding: 00071
Shop #: WSC 00094
VCID: 67DC8300056DD57E30-4B00
VWZ7Z0D9871964

3 Faults Found:
17564 - Manifold Pressure Sensor (G71)
P1156 - 35-10 - Open/Short to Ground - Intermittent
17824 - EGR Valve (N18)
P1416 - 35-10 - Mapped Regulation Range Exceeded - Intermittent
16496 - Intake Air Temp. Sensor (G42)
P0112 - 35-10 - Signal too Low - Intermittent
Readiness: 1110 0101

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 6R0-907-37x-ABS80.clb
Part No SW: 6Q0 907 379 AA HW: 6Q0 907 379 AA
Component: ABS 8.0 front H03 0001
Revision: 00000000 Serial number: 00000000000000
Coding: 0000005
Shop #: WSC 00788 785 00200
VCID: 7CF6CC6C3CEB66A6CD-515A

2 Faults Found:
01314 - Engine Control Module
013 - Check DTC Memory - Intermittent
18256 - Please check DTC Memory of Engine Controller
P1848 - 000 - - Intermittent

-------------------------------------------------------------------------------
Address 09: Cent. Elect. Labels:. 6Qx-937-049-C.lbl
Part No: 6Q1 937 049 D
Component: 0000 BN-SG. 1S34
Coding: 25790
Shop #: WSC 00788
VCID: 3C760C6C2C6BA6A68D-513C

1 Fault Found:
01598 - Drive Battery Voltage
07-00 - Signal too Low

-------------------------------------------------------------------------------
Address 15: Airbags Labels: 6Q0-909-605-VW5.lbl
Part No: 1C0 909 605 K
Component: 16 AIRBAG VW51 0N 0008
Coding: 12598
Shop #: WSC 00788
VCID: 2C563C2CDC0B36261D-515A

1 Fault Found:
00532 - Supply Voltage B+
07-10 - Signal too Low - Intermittent

Thanks,
hooolagon
New
Posts: 8
Joined: Sat Dec 24, 2022 1:45 am
Drives: VW 1.4 BKY
Location: UK

Re: VW Polo 1.4 BKY engine cranks but won’t start

Post by hooolagon »

Compression tester arrived and unfortunately there is absolutely no compression in all four cylinders, I did go above and beyond and bought 4 of those spark plug lights which is nice, the engine was getting spark from all the coil packs, the light on the tester for cylinder 2 was significantly dimmer than the other cylinders but it did exist.

Having never seen the engine run myself and also swearing that my timing marks are correct especially with TDC, can I rule timing out and is it time for me to pull the head?

If so I have two options here I think; personally… I could get a replacement engine and throw it in or I could pull the head inspect for issues and replace bent valves… I like to work on cars myself so I’m not worried about the economy of it all, which would be easier… 50ish bolts away from removing the cylinder head, or mess around with the engine later and throw a cheap known good engine in, I already have all the tools so which would you guys choose?
hooolagon
New
Posts: 8
Joined: Sat Dec 24, 2022 1:45 am
Drives: VW 1.4 BKY
Location: UK

Re: VW Polo 1.4 BKY engine cranks but won’t start

Post by hooolagon »

I have two concerns:

Could someone have rotated a crankshaft so it’s out by 360 degrees, i.e. the hole lines up but the cam lobes are incorrect relative to the crankshaft…

I doubt that’s even possible as I’m assuming the engines are designed in a way this couldn’t happen… and if it was the case, though highly unlikely; it would almost guarantee bent valves…

My second concern is if I take the cylinder head off and the valve seat has signs of damage meaning either reseating them which isn’t cost efficient, or a replacement used cylinder head…

Finally, I don’t see signs of pistons and valves having damaged each other but what I will do for peace of mind… is check TDC and the cams for fitment (I am using an 8mm drill bit - that could be a reason) and secondly I might use the endoscope to confirm valves and pistons haven’t made contact… hopefully that means I ruined timing somehow… or I’m completely wrong on all accounts…

Nothing but time to spare 🤣

Appreciate the support so far
hooolagon
New
Posts: 8
Joined: Sat Dec 24, 2022 1:45 am
Drives: VW 1.4 BKY
Location: UK

Re: VW Polo 1.4 BKY engine cranks but won’t start

Post by hooolagon »

TDC was perfect, I used a dial indicator… the cam shaft holes were aligned perfectly, so I reckon the valves are bent, there’s a very slight curved slash on the pistons judging from the endoscope so I guess the pistons and valves kissed which is a shame…

Luckily doesn’t look like it’ll be too difficult to pull the head and see the extent of the damage… I’ll be back soon with updates within a couple of months

Thanks guys 👍 hope this helps someone
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