Hi guys, Iv just bought myself a version 3 STi and seem to be having a couple of issues.

I viewed the car Sunday and everything was fine, picked it up last night and it was perfect on the journey home.

Issue 1:
However, I called into a garage just before I got home just to check tyre pressures and left the car to idle whilst I was doing this.
It was idling for perhaps 10mins when the car sort of shuddered (like when the fan kicks in) and it kept doing this, I looked at the rev counter and it was fluctuating between around 600-1500rpm. I finished the tyres and got back in the car and then noticed the temp gauge had risen to just under 3/4 mark. Home was about 1/2 mile away so I started to drive back and everything went back to normal.
The car drives perfect, no loss of power, no smoke or fluid loss, gauges reading normal.

Issue 2:
When I got home I parked on the drive and left the car to idle again, maybe 5mins and everything was fine but just before I turned it off I could hear a sort of pumping noise (almost like a very loud heart beat!) from the back of the car so I turned it off and it was still making this noise, got out and locked the car and it was still doing it! Popped the boot and looked in the flap where the jack lives and it's coming from in there so guessing it's the fuel pump? Or do these have in tank pumps?
With it still making this noise I got back in the car and started the engine and the noise was still there, turned it off still making this noise, went to have a look under the car and then it stopped.
It has an uprated pump but Iv had cars with these before and never known this before.

Any help or advice appreciated.
Thanks

 

The noise from the boot is probably your Automatic aerial, mine does it, i let the aerial extend then disconnected the plug, its on the left hand side, remiove the boot lining at the arch area and you will find it

the fuel pump is more under the rear back seat

 

Yes it is on the aerial side now you've mentioned it.
That would make sense, I don't listen to radio anyway so might leave it in the down position.
Thanks for that.

Any idea on the other issue?

 

Might be head gaskets gone, or a dodgy MAF.

 

Hope it isn't that!
It's running mafless although the MAF is still on the induction pipe

 

OK, discount that. The temperature rise makes me wonder if it's headgaskets or running lean?

Who mapped it? Does it maybe want a tweak?

 

Duncan at race dynamic I believe.
Iv got the dyno graph and AFR looks about right 11:2 on boost.
I don't think any changes have been made since.

Just had another look under bonnet and oil and water looks nice and clean.
One thing I have thought of is that I can't remember if the rad fan came on, now this would explain the temp gauge rising but what about the fluctuating idle?

 

Maybe the fans seized and its taking a lot of current from the alternator. I would check the fan works first.

 

why not leave the car to get hot again and see if the fan kicks in ?
simple way to test your theory . . .

 

Have you ever cleaned out the throttle body?

 

Iv only had the car a couple of days so I haven't done anything to it except drive it home!
Do both fans come on together when it gets to a certain temp or does the aircon fan run as soon as the aircon is switched on?

 

aircon fan runs with the aircon. Other fan is controlled by engine temp sensor.

 

Might have been an airlock in the coolant system luckily it's right now or get it checked by a competent garage in case there's a leak etc hope all goes well mate and you enjoy the motor and it's not the Headgasket

 

It's not sorted yet as i haven't had much time to check everything over.
I'm planning to take it for a run at weekend and check if the fans actually come on, then il go from there

 

Ok, iv had the car out for a good run and the fans do not come on.
Iv looked round and found that the connector from loom to fan wiring has melted on one side and looks like it has allowed water to get into the pins, the middle pin is quite corroded the other two don't look as bad, so I tried to clean it up best I can but the fans still aren't kicking in.

Connector melted on right hand side


Corrosion on pins


Im guessing this is whats causing the problem!
Anyone got a classic engine fan connector with a decent length of wire on the back of it?

 

Not saying this isn't the fault , but it takes a very hot day for my rad fan to kick in, it's hardly ever on in this weather no matter how long it idles .

 

I took the car for a good 20 mile drive and then let it idle, after around 5-10mins at idle I can sort of "feel" the fan trying to come on. The temp gauge starts to gradually rise aswell but soon as start moving the temp goes to normal again.
Seems a coindence if that connector wasn't at fault??

On another note it was the aerial making the noise at the back so unplugged it and its all ok

 

If the fans spin freely by hand you can try running a temporary feed and earth from the battery to the fan side connector to see if they power up.

Mick