Plug unplugged from my vr6 engine? what is it?

[rixy 0]

hi there every1, i have recently fitted my engine back into my raddo, (vr6) and have noticed a multi plug not attatched to anything at the front, next to the mount. Does anyone know what it is, or where its for? I have the plug next to it connected - this one goes to the sensor on the f ront of the block, however, im not sure where / what this other one is for.

 

I think it is a 3 wire plug, and has a separate smaller wire along side it - possibly an earth?

 

Please help, as im sure it was connected a year ago when i r emoved the engine, just cant remember where to, lol

 

The plug looks like it should be clipped into the plug stay on top of the front engine mount, cheers everey1?

[Goldie 2]

Any chance of a picture??

[CrazyDave 0]

Sounds like it may be either the VR Crank sensor or Front Knock Sensor both colour coded so difficult to get wrong.

 

Both need to be fitted. But it will run without the knock sensor.

[rixy 0]

ok cool, cheers, but where i theh knock sensor situated? havent got anything to plug it into, so im thinkin maybe i have no got a knock sensor fitted? if not, i need to get one, lol.

[rixy 0]

just had another look, basically, there is a sensor wire that runs under the engine from the front mount? this has a white plug on it - this one is connected.

 

However, there is a 3 wire plug next to it (clipped to the side of the starter motor) that has a black plug - this is the one that is not connected, and it has a smaller single wire spade terminal next to it - this is also not connected? where do they go?

 

Im getting crap economy which makes me think its a sensor?

[CrazyDave 0]

The white one is the crank sensor, so thats why the engine runs at all.

 

The black one is the front knock sensor. It's just bolted to a threaded hole on the front of the block (in the middle ish).

 

Not sure if this would cause bad economy, but you do need one for it to run correctly, or the ecu may pull all the timing advance for the front cylinders.

 

Hope this helps?

[rixy 0]

ok then, cheers, will look in my box of spares tomorrow and retro fit the old one , obv didnt buy a new one for some reason? will let ya know how i get on - seems reasonable as the car does seem to have a funny flat spot when accelerating mildly harder than normal - just doesnt feel right if ya know what i mean, cheers again.

[Yandards 0]

The white one is the crank sensor, so thats why the engine runs at all.

 

The black one is the front knock sensor. It's just bolted to a threaded hole on the front of the block (in the middle ish).

 

Not sure if this would cause bad economy, but you do need one for it to run correctly, or the ecu may pull all the timing advance for the front cylinders.

 

Hope this helps?

 

The ECU will pull the front 3 cylinders back by 12 degs, same power loss as you get when you loose the cam pos sensor, although its only on 3 cylinders.

[rixy 0]

awesome, cheers everyone. Had a look today, i know the sensor attatches just above the oil filter / cooler housing, but what is the best way of fitting it there when the engine is in, slam panel etc all fitted? Is the best and easiest way to remove slam panel etc, so you can get at it from the front? Or can i get at it from aboven if i remove the inlet etc?

[CrazyDave 0]

awesome, cheers everyone. Had a look today, i know the sensor attatches just above the oil filter / cooler housing, but what is the best way of fitting it there when the engine is in, slam panel etc all fitted? Is the best and easiest way to remove slam panel etc, so you can get at it from the front? Or can i get at it from aboven if i remove the inlet etc?

 

Not easy to get at with the front on, from underneath would be your best bet, but not much room.

 

We did manage to get a crank sensor off / back on again at the weekend without removing the front but the knock sensor is a bit higher up.

 

Good luck!

[rixy 0]

looks slike i got me a job for saturday morning then, ha ha! Will also make sure engine is cold, because my god did that manifold burn my arm last night, lol!

 

Will let ya all know how i get on, cheers every1

[rixy 0]

My god what an arse of a job ! Not a bad job to du, but taking apart my car - thats only been together for 2 weeks is sooooo soul destroying, lol! Nevermind all sorted now thank god.

 

Took a few piccy's on the way to help others out if needed!

 

Basically, you have to remove complete front end - bumper, headlights, slam panel, etc to get to it easier. In doing this you have to drain water system of all coolant. I also removed both coolant pipes from the oil cooler to aid me getting the bolt in the sensor.

 

This took me about 2.5 hours to do, and only about 20 secs of that was actually fitting the sensor, lol. What a bummer - if only i'd fitted it before i put the engine in, lol! Typical!

 

Pic 1 :- Before i started

 

Pic 2 - After about 30 mins

 

Pic 3 - After 45 Mins - All ready to have a go at it now

 

Pic 4 - Close up of where the sensor goes - The little shiny surrounded Hole in the block - Just above but between the oil filet housing and the sandwich cooler! (above the oil sender on the right)

 

Anyway, car is now run in, and has fresh synta silver in her - new genuine pas fluid, and new genuine coolant etc and my god does it pull like a train now! That sensor really does knock the power down a bit. Economy is now much much better also, easily sits at 35mpg now, instead of struggling to hit 28, lol!

 

Cheers everyone for your help:-

 

Just one more thing though. Next to the plug for the knock sensor 2 - there is a singal wire - comes from the same loom, has a single female spade connector on it - wire is couloured yellow with black trace - Where does this go? couldnt find anywhere to plug it onto but it must go somewhere?