*Urgent help needed please - overheating 3.0si*

[RyanB88]

Hi

Car - 2006 3.0si, 105kish miles

Around 6 months ago, with the help of my friend Chris on here (thanks again Chris!) we changed the water pump on my si due to a fault code. Although there was no real symptoms, it was more preventative maintenance. All went fine and the fault code dissapeared.

Fast forward to today, I was driving to work and I noticed that the fan was blowing out cold air, even after 5 minutes, where normally there would be some warmth in it. I thought nothing of it and carried on listening to my music and driving. After about 20 minutes, I wanted some heat and tried again - it still came out cold. The temperature gauge was in the middle as normal and all seemed ok. Car still drove well as normal.

After approx 25 mins of driving, I got some warm air come through the vents. As I entered the work car park (approx 30 mins into the drive) I noticed that the temperature gauge was shooting up, but I kept an eye on it and it never went into the red or too high. Parked up and turned my engine off and I could hear what I imagine was the fan or maybe the pump still running for a good period of time.

Drove home tonight and had a similar situation, but it was over heating quicker, every 10 minutes I had to turn the engine off and leave it for 30 minutes with the engine up to get it to cool down. Managed to limp home finally. Car is on the drive now and still drives perfectly but is over heating for some reason

Plugged in Carly and it's given me fault codes:

002E84 - Electric coolant pump communication

002E81 - Electric coolant pump, speed deviation

Now I fitted a brand new water pump only a few thousand miles ago, so my way of thinking is that although it's got two fault codes, I'm thinking something else is causing this and the knock on effect is the car thinks the water pump has gone? Some kind of air lock maybe?

Any advice please as I can't drive my car again right now

Thanks

 

[ph001]

You know there is an automatic bleed procedure you can do right? I assume you did this when changing the pump? I would run that agsin anyway to see if it helps otherwise it looks like another new pump to me, but I would give the elecrical connector and associated wiring a good inspection also.

There is an electronic thermostat next to the pump as well but I’ve never known one of them fail and in any case it would throw its own code. Did you change the stat out of interest?

 

[Smartbear]

I’d look into the guarantee that came with the new pump after checking the associated wiring as mentioned above.
I wouldn’t drive again while it’s overheating like that
Rob

 

[ph001]

Here's a video on the bleed just in case it's any help... https://www.youtube.com/watch?v=Nzk9yvFXsBI

 

[Scooba_Steve]

The pump comm code makes me think it's an issue with the pump. Check connections, maybe clean and bleed. I'd also be contacting the seller to let them know and to also ask for any troubleshooting. What brand and who from?

 

[ph001]

I did notice there are some Chinese aftermarket pumps now appearing on Ebay which are not Pierburg for about £120. What did you buy?

 

[Chris1981]

We ran the bleed procedure a few times to ensure there was hot air coming through into the cabin and its been fine for months, the in consistent hot air an over heating is a new issue... could be an airlock but how would air get in? should we be looking for leaks? Any common places/failures to focus on?

The pump was i believe genuine Pierburg rather than a cheap Chinese one, certainly looked genuine, high quality and in Pierburg packaging, Ryan ordered it from Germany if i recall.

Replaced the thermostat at the same time with a ECP one i'd bought when i though mine had gone (turned out the plug had just come loose on mine!), I think it was a circoli... reading reviews now and they are mixed bag, some people saying they fail internally or leak which is a bit concerning! Could a failure of the thermostat give these errors on the pump?

I was initially leaning toward early pump failure or lose wiring/wiring issue based on the codes, but those reviews have me thinking crap thermostat from ECP now...

 

[ph001]

I just think it would be unusual to throw those pump codes if it was the stat.

 

[RyanB88]

We ran the bleed procedure a few times to ensure there was hot air coming through into the cabin and its been fine for months, the in consistent hot air an over heating is a new issue... could be an airlock but how would air get in? should we be looking for leaks? Any common places/failures to focus on?

The pump was i believe genuine Pierburg rather than a cheap Chinese one, certainly looked genuine, high quality and in Pierburg packaging, Ryan ordered it from Germany if i recall.

Replaced the thermostat at the same time with a ECP one i'd bought when i though mine had gone (turned out the plug had just come loose on mine!), I think it was a circoli... reading reviews now and they are mixed bag, some people saying they fail internally or leak which is a bit concerning! Could a failure of the thermostat give these errors on the pump?

I was initially leaning toward early pump failure or lose wiring/wiring issue based on the codes, but those reviews have me thinking crap thermostat from ECP now...

Everything chris said is bang on. I’ve checked the wiring today and nothing seems loose

 

[RyanB88]

To add to my thermostat assumption, the main radiator is stone cold after 20 minutes of running. Surely if it’s the water pump then the radiator wouldn’t be cold?

 

[VRSteve]

To add to my thermostat assumption, the main radiator is stone cold after 20 minutes of running. Surely if it’s the water pump then the radiator wouldn’t be cold?

If the pump isn't pumping then of course the Rad will be cold, no water will be circulating. Given the codes you have I wouldn't spend too much time looking at the stat.

If you take the top off the expansion tank you should be able to see water flowing through the return pipe, if the pump is pumping. Obviously don't do this if the system is under pressure.