Advice please - 5F Engine rattling

[immiH]

Hi All

This is my first post here, what a great forum!

Vehicle Details
SEAT Leon FR DSG 1.8 Petrol
Reg: 63
Mileage 123k
Ex-police

Maintenance history well documented
Bought 8 months ago

Background information
Was loosing coolant about 4 months ago and had some work done to replace a whole host of items including spending over £1k on :
- Thermostatic Housing and new tooth belt
- water pump and new union
- oil cooler, gasket and internal valve

After the work the garage did the oil cooler was leaking and it was identified the part was the problem. Took the car to SEAT and they said the work wasn't done to spec and they could not get a replacement part from TPS. The original garage then had the car for a week and replaced the offending part. I have no idea whether this was new or not, no receipt supplied.

There was still a little coolant loss, needing an occasional top-up.

A few days ago, heading down the motorway "Low Oil Pressure" warning flashed up on the dash and advised to immediately stop. Pulled off the motorway and switched off the engine. Called road-side assistance and the mechanic identified that the "piston cooling jet" had popped out and the bolt had sheared off (image attached). We were lucky to extract the bolt shaft and put in a temporary fix (now replaced with correct bolt). Put fresh oil in and started the car.

Was a little lumpy to start with but as oil got round ran really smoothly. I asked the AA Mechanic what could have caused the bolt to shear off like that and he suggested that it was possibly overtightened and as oil pressure built up is just snapped off.

Drove really nicely after this and no issues.

A couple of days later, started the car in the morning an it sounds like a diesel. Lots of rattling and a bit lumpy.

Went back to the mechanic who without any diagnostics said "mate, needs a new engine" and suggested something had broken and caused the "piston coolant jet" to be forced out. That makes no sense to me as after the incident the car ran smoothly for 2-3 days. If there was a "broken" part it would have not taken three days of motorway and general driving to show up (maybe I'm wrong?)

I pulled off the sump and checked the strainer in the oil suction pipe, cleaned it out (was very small amounts of dirt, nothing major). Replaced the oil filter and filled oil. On startup was noisy as the oil got round and then sounded fine for 20 seconds, but then rattle and lumpy again. When revs are up, above 3.5k the rattle disappears and all seems fine, as soon as the revs drop there's a "timing" issue, which I think it caused by the low oil pressure.

I took off the oil filter to see if there was oil pressure (next step is to put on an oil pressure tester) but the oil only filled slowly on crank (disconnected the coil packs to prevent engine startup), I was expecting a fountain of oil.

Is the oil pump a culprit in all this and the work that was done originally a red-herring?

Any thoughts, guidance and advice would be very much appreciated please.
I am a novice mechanic (motorbikes mainly) but have a collection of tools that I have built up over the years and am quietly confident to give things a go. I follow the instructions, watch videos, take my time and happy to take advice)

Thank you so much for reading.

 

[adam davies]

Hi All

This is my first post here, what a great forum!

Vehicle Details
SEAT Leon FR DSG 1.8 Petrol
Reg: 63
Mileage 123k
Ex-police

Maintenance history well documented
Bought 8 months ago

Background information
Was loosing coolant about 4 months ago and had some work done to replace a whole host of items including spending over £1k on :
- Thermostatic Housing and new tooth belt
- water pump and new union
- oil cooler, gasket and internal valve

After the work the garage did the oil cooler was leaking and it was identified the part was the problem. Took the car to SEAT and they said the work wasn't done to spec and they could not get a replacement part from TPS. The original garage then had the car for a week and replaced the offending part. I have no idea whether this was new or not, no receipt supplied.

There was still a little coolant loss, needing an occasional top-up.

A few days ago, heading down the motorway "Low Oil Pressure" warning flashed up on the dash and advised to immediately stop. Pulled off the motorway and switched off the engine. Called road-side assistance and the mechanic identified that the "piston cooling jet" had popped out and the bolt had sheared off (image attached). We were lucky to extract the bolt shaft and put in a temporary fix (now replaced with correct bolt). Put fresh oil in and started the car.

Was a little lumpy to start with but as oil got round ran really smoothly. I asked the AA Mechanic what could have caused the bolt to shear off like that and he suggested that it was possibly overtightened and as oil pressure built up is just snapped off.

Drove really nicely after this and no issues.

A couple of days later, started the car in the morning an it sounds like a diesel. Lots of rattling and a bit lumpy.

Went back to the mechanic who without any diagnostics said "mate, needs a new engine" and suggested something had broken and caused the "piston coolant jet" to be forced out. That makes no sense to me as after the incident the car ran smoothly for 2-3 days. If there was a "broken" part it would have not taken three days of motorway and general driving to show up (maybe I'm wrong?)

I pulled off the sump and checked the strainer in the oil suction pipe, cleaned it out (was very small amounts of dirt, nothing major). Replaced the oil filter and filled oil. On startup was noisy as the oil got round and then sounded fine for 20 seconds, but then rattle and lumpy again. When revs are up, above 3.5k the rattle disappears and all seems fine, as soon as the revs drop there's a "timing" issue, which I think it caused by the low oil pressure.

I took off the oil filter to see if there was oil pressure (next step is to put on an oil pressure tester) but the oil only filled slowly on crank (disconnected the coil packs to prevent engine startup), I was expecting a fountain of oil.

Is the oil pump a culprit in all this and the work that was done originally a red-herring?

Any thoughts, guidance and advice would be very much appreciated please.
I am a novice mechanic (motorbikes mainly) but have a collection of tools that I have built up over the years and am quietly confident to give things a go. I follow the instructions, watch videos, take my time and happy to take advice)

Thank you so much for reading.

Its normal practise to change oil pump when doing the water pump, especially at that mileage.

Rattle could be many things, dual mass fly wheel, clutch, timing chain/ tensionser. Work your way through these items and eliminate them then come back to us.
If you have no oil pressure or low oil pressure that would defo be your probpem with rattles. Please if you have low oil pressure dont start it just get it to a vw independant.

 

[immiH]

Its normal practise to change oil pump when doing the water pump, especially at that mileage.

Rattle could be many things, dual mass fly wheel, clutch, timing chain/ tensionser. Work your way through these items and eliminate them then come back to us.
If you have no oil pressure or low oil pressure that would defo be your probpem with rattles. Please if you have low oil pressure dont start it just get it to a vw independant.

Thank you for that advice Adam

I'll :
1. Conduct an oil pressure test
2. Depending on results get a new oil pump (I should be able to do this myself on drive-on ramps)
3. Depending on 1 and 2 above get it down to a VW independent, there is one highly recommended one in Bradford

Appreciate your reply, thank you

 

[immiH]

Follow-up on oil pressure test, do you know what the pressure reading should be?

 

[adam davies]

Follow-up on oil pressure test, do you know what the pressure reading should be?

Something like 15 - 25 psi af idle and when reved that should increase well past 25 as pressure of the oil is imcreased at higher revs.

 

[adam davies]

Follow-up on oil pressure test, do you know what the pressure reading should be?

You should also read the fault codes to ensure that its not related to an oil sensor that may be at fault. Do this after youve tested oil pressure manually, so that you can then rule out the any oil sensor faults

 

[immiH]

Hi All

I'm replacing the oil pump as a first step and wanted to check on the part code, the one in the vehicle at the moment is 06H 115 105 AN, does the replacement one have to be identical, including the AN bit?

What do the codes mean?

Thank you

 

[adam davies]

Hi All

I'm replacing the oil pump as a first step and wanted to check on the part code, the one in the vehicle at the moment is 06H 115 105 AN, does the replacement one have to be identical, including the AN bit?

What do the codes mean?

Thank you

Ring vw seat give them the part no and ask them for the newest part number revision and price. Part numbers get revised regurally for updated parts.

 

[immiH]

Ring vw seat give them the part no and ask them for the newest part number revision and price. Part numbers get revised regurally for updated parts.

Good morning - hope y'all had a great weekend.

I called SEAT and they told me they can't tell me the part number, but it's had a fair few revisions.
Called TPS and they said they couldn't deal with me as I am not trade.

Advice on other options would be great please.

Thank you
Part number for current oil pump is : 06H 115 105 AN