My mums got a 1997 1.0lt AER and she mentioned that there was a "red light that keeps coming on with a can on it". I checked the oil and it was a touch low so put about half a litre in it. It wasnt major low and not below the minimum. I started the car and the oil light stayed off so i assumed it was fine.

I've just had a phonecall from my dad to say that its doing it again. He reckons its fine when cold but the light flashes like and indicator with a set rythm once the cars warmed up. He said the engine sounds normal with no noises and isnt tappy. He said the oil looks really thin.

I've suggested change the oil and filter as its not been done since they had it, but was serviced regular before then. They have done about 7-8k since they bought it. It just seems a bit strange that its flashing at a regular flash rate once the cars warmed up.

Anyone got any suggestions.

Hes also mentioned that its holding back alot once its warm. He said its fine from cold but after about 3-4 minutes its holding back. He says it doesnt feel like a missfire. I've suggested maybe a faulty lambda as it had a lambda fault code when i scanned it 6 months ago with VCDS-lite. I've said id bring my oscilloscope around and scope the sensor and see whats happening. Any more thoughts on this one. The holding back was there before the oil light and I dont think they are related

Any help gratefully received.

Definately overdue for a service! should of had the service reminder come up on the speedo ? If it continues get a replacement low pressure switch or a pressure gauge to see what pressure it is running at?

The other problem could be either lambda or coolant temp sensor, but a scan should show these up

Definately overdue for a service! should of had the service reminder come up on the speedo ? If it continues get a replacement low pressure switch or a pressure gauge to see what pressure it is running at?

The other problem could be either lambda or coolant temp sensor, but a scan should show these up

The oil and filter is getting changed tommorow. Whats the service intervals on these. Is it 6k. The service reminder is on. I'm hoping its nothing too serious. If its still flashing after the oil change ideally I need to take it and get the pressure checked as I do not have a guage for this but as the switches are only cheap I might just swap it. Were about is the pressure switch on these. Failing that its going to be a sump off job to check the strainer.

I need to re-scan it again for codes and also have a look at the live data and see what the sensors are doing. Id like to test the lambda before replacing as I've seen so many replaced when there was nothing wrong with them. My gut feeling is the lambda is sticking and isnt switching. This would could explain the car running fine until the car enters closed loop mode.

Edited 17 May, 201313 yr by marks152

3-4 mins is a bit quick for it to be going into closed loop config, but vagscope will confirm that.

It might be as well to replace the pressure switch anyway as they are as you say cheap, it's under the inlet manifold between #1 & 2 cylinder

3-4 mins is a bit quick for it to be going into closed loop config, but vagscope will confirm that.

It might be as well to replace the pressure switch anyway as they are as you say cheap, it's under the inlet manifold between #1 & 2 cylinder

Can you get at the switch without taking the manifold off?

3-4 mins is a bit quick for it to be going into closed loop config, but vagscope will confirm that.

It might be as well to replace the pressure switch anyway as they are as you say cheap, it's under the inlet manifold between #1 & 2 cylinder

Can you get at the switch without taking the manifold off?

Yes

Yes

Thats good news. I've never done any work to the engine on it since shes had it. I'm sure ill find my way around it once I start looking. Any tips?

It's all pretty straightforward, if you do drop the sump there are grooves in the flywheel that make it easier to get at the rear bolts on the pan, ball headed hex keys make it easy, torque to 15Nm.

If you can get a pressure gauge

At 2000 rpm and an oil temperature of 80 °C the oil pressure should be at least 2.0 bar.

It's all pretty straightforward, if you do drop the sump there are grooves in the flywheel that make it easier to get at the rear bolts on the pan, ball headed hex keys make it easy, torque to 15Nm.

If you can get a pressure gauge

At 2000 rpm and an oil temperature of 80 °C the oil pressure should be at least 2.0 bar.

Cheers Nige. Thats a great help. Lets hope it doesnt come to that. I know a few mechanics so I'm sure I could borrow a guage if need be. Thanks for you help.

Ill update the thread tommorow once the oil/filter has been changed.

One last question. Were about the temperature sensor on this engine. Ill remove it and bench test it checking that its resistance in linear as it gets hotter.

One last question. Were about the temperature sensor on this engine. Ill remove it and bench test it checking that its resistance in linear as it gets hotter.

The coolant sensor is a dual element one for the gauge and the the other for the ECU, the ECU uses pins 1 & 3 ( Blue & Brown/Green wires)

Examples:

◆ 30 °C is in range A and corresponds to a resistance of 1.5...2.0 kω

◆ 80 °C is in range B and corresponds to a resistance of 275...375 ω

It's on the front face of the thermostat housing

Cheers nige. ill have a look through autodata and get a pinout for the sensor so i can test it correctly or an easier option might be to fit a 250ohm resistor across pin 1 and 3 of the wiring to fool the ECU. I've got one of them in my box of bits. Might be worth trying. I always have some various resistors for jobs like this. Cheers for the diagrams and pictures.

I assume that the metal pulls out from the housing and the sensor pulls out, then the new ones fitted and the metal locking tab refitted.

The sensor is held in with a plastic clip, just pulls in/out, the "O" ring often gets stuck in the housing, so just check if refiting a new one, Part number 357919501A

temperature sender / for coolant temperature gauge / and / electronic control unit 20MM 4 pin black/yellow / AEA,AEV,ADX, AEE,AGD,AFH, AHS,AER,AEX, AHG,AKU,AKV, ALL,ANX,AFK

030919081B oil pressure switch / F 6N-W-000 001>> 0,5BAR M10X1 1 pin green / AER,AEX,AHS AEE,AKV,ALL, ANX,APQ,AFH

The sensor is held in with a plastic clip, just pulls in/out, the "O" ring often gets stuck in the housing, so just check if refiting a new one, Part number 357919501A

temperature sender / for coolant temperature gauge / and / electronic control unit 20MM 4 pin black/yellow / AEA,AEV,ADX, AEE,AGD,AFH, AHS,AER,AEX, AHG,AKU,AKV, ALL,ANX,AFK

030919081B oil pressure switch / F 6N-W-000 001>> 0,5BAR M10X1 1 pin green / AER,AEX,AHS AEE,AKV,ALL, ANX,APQ,AFH

At least I know what I'm looking for now. Cheers.

Shes just arrived at my house with the oil light flashing. The engine sounded sweet as a nut even at high RPM. I've just changed the oil and filter and its stopped flashing. The oil that came out looked as you would expect and no signs of any metal in it. It was black as hell but nothing too worrying. I left it running for about 15 minutes after the oil/filter change and it wasnt flashing when she left so I'm hoping that might have sorted it.

Shes driven it the 3 mile home and its not come back on. I did tell her to take the long route home and run it about 6 mile but she just took it straight home. My dad said he done about 3 mile this morning before it came on so its not 100% confirmed that its cured the issue. Time will tell I suppose. If not then ill pick a new switch up. I dont think its anything serious. The engine sounds too quiet for oil starvation.

I never got chance to look into the holding back as it started raining. I'm more concerned about the oil light for now. Its been holding back since she bought it and I'm sure its nothing to serious. Shes going to pick a set of plugs and a air filter up this week for me to fit. I want to get the service complete before i start fault finding the holding back issue.

BUGGER - Its back on again.

Ill try get a new switch tommorow and see what happens. Well at least the oil and filters been done so its will be ok for another year.

Any idea which switch to get. Is it a case of you get what you pay for or will either of the cheaper ones work fine.

http://www.gsfcarparts.com/parts/engine-pa...pressure-switch

Edited 18 May, 201313 yr by marks152

That link just takes you to the "enter your reg"

There are two switches listed on vagcat, the one I posted previously and another @ 0.35bar for earlier cars.

If you put the VW part number from the other post it comes back as GSF part no 931VG0500 £10.14

That link just takes you to the "enter your reg"

There are two switches listed on vagcat, the one I posted previously and another @ 0.35bar for earlier cars.

If you put the VW part number from the other post it comes back as GSF part no 931VG0500 £10.14

Its a pity they dont open sundays. I'm on 2-10pm in work this week so ill do it after the school run in the morning and then go and fit it. Looks straight forward to fit. Cheers again

I've just been to GSF and picked up the oil pressure switch and fitted it. It was a nice easy job but while i was there I noticed that number 3 plug lead was sitting about 1 inch higher than the rest. The bloody thing wasnt pushed onto the plug. I heard it arcing when i had the engine running checking for leaks after fitting the new switch.

I've checked the air filter and it looks clean.

I've ran a scan with VCDS lite and got a couple of fault codes.

The first was the idle motor needs adapting as the batterys been off about 6 months ago but the car idles fine so I'm not too worred about this one, but more concerning is a fault code for the knock sensor - open circuit. This ones concerning me especially with the oil light coming on aswell. Maybe this is also pointing to the oil pump. It was the "open circuit" description that is confusing me. That doesnt sound right. Is this code set when the oil lamp comes on.

I didnt write the exact codes down as my laptop died before I got chance to save it. Sorry!

I've advised her to take it for a run and if it comes back on then its going to have to have the pressure checked and at best a new pump, at worst maybe drop another motor in if its already done damage. I cant understand it as the engines very quiet even at high RPM when the light was flashing. Very strange.

The knock sensor would'nt indicate an oil pump fault as it's looking for pre-ignition (pinking) It's fitted on the block between 2 & 3 cyl It's a bitch to get at without removing the inlet manifold or the starter motor.

This picture is for the earlier engine, but the only difference is this shows a 28 pin round main engine loom disconnect #2 yours should have a couple of rectangular ones

I'd start with checking the condition of the connector on the sensor #10 then the condition of the main disconnect plugs. If you want to do a continuity check back to the ECU

Sensor pin 1 to ECU pin 39

Sensor pin 2 to ECU pin 19

Sensor pin 3 to ECU pin 45

I've cleared the code and ran it and its not come back nor has the oil light yet but it needs to do about 6 mile but i cant drive it as I dont have a licence. I agree with you about the knock sensor picking up pre ignition but most of my work is on vauxhalls and quite often if the owners let the oil run low you end up with a knock sensor code(p0325). This is what has me worried. Ill keep an eye on it and fingers crossed they are not related.

I've cleared the code and ran it and its not come back nor has the oil light yet but it needs to do about 6 mile but i cant drive it as I dont have a licence. I agree with you about the knock sensor picking up pre ignition but most of my work is on vauxhalls and quite often if the owners let the oil run low you end up with a knock sensor code(p0325). This is what has me worried. Ill keep an eye on it and fingers crossed they are not related.

That's a wierd one, unless the vauxhall with low oil is somehow destroying the sensor with the vibrations of a dying engine? but yes if there's no obvious rattles or bangs, let it run for a while then rescan and see if it throws up anything?

The light back on after 5 mile. Maybe the pressure releif valves stuck. Any idea were it is. I know on vx its behind the canister oil filter. maybe it just wants freeing up. I've seen this a few times with vx engines.