Unknown attachment to plug lead!!

[mmacneill123 0]

Hi, as part of my amateur servicing i ordered a new set of plug leads and was happily fitting them when i noticed that one of the existing plugleads has what looks like a big polo (as in sweet... :-) ) attached to the lead which is obviously a sensor of some kind as it goes to an electronic plug... Now obviously my new plug lead does not have one and there is no way (as far as i can see!!!) that you could possibly get that big polo onto the lead.

 

Any info as to what it is and where/if i can get a lead with one on?? I have a 2L/16 9A engine code and it is the plug lead at the dizzy cap end.

 

Cheers!

[james153 0]

that is your camshaft sensor. Fairly integral for the running of the engine. should be on the no.4 HT lead.

 

im not 100% this is totally advisable, try it on another old lead first but on the plug end simply pull the lead out of the plug cap then the sensor will slide off. lead should just push back into the cap with a satisfying click. if this is sucessful then do that.

 

Hope this is of help.

[mmacneill123 0]

Thanks for that, will try that!

[mmacneill123 0]

Cannot seem to get either end of a plug lead out, thy both look moulded in!!! Any ideas anyone??

 

Incidentally, the car seems to run absolutely fine without it on, which makes me doubt is it a cam position sensor which i would imagine would have quite a noticeable effect?

[bmwcompact 10]

I had the same issue a couple of days ago. I got my car a few weeks ago and found the impulse sendor unattached. When I found it should go around lead 4 (thats what the Haynes Manual 1647 says for A9 engine as fitted to the Passat), I checked the forum. Lots of posts said it should be on lead 1 ie timing belt end of engine. I didnt think the end would come off the lead either by pulling or unscrewing-I didnt want to wreck the lead. I too thought they were moulded (genuine VAG leads). Eventually I found the fitting did twist and pull off at the distributor end. It was a tight fit getting the metal clip on the end of the lead through the inpulse sensor (the polo). I then replaced the lead fitting.

 

I havent noticed any difference in the way the car performs and wondered whether my impulse sender was in fact working-I went with Haynes and put it on lead 4 (gearbox end of engine). So I'd be interested to hear any comments on what this impulse sender is supposed to do! (It would seem to me to be a feedback loop, indicating to ECU when spark occurs in cylinder 4, to be compared with when the ECU intended it to occur??)

Edited March 17, 2012 by bmwcompact

[Jim 2]

This seems to come up on an pretty much yearly basis! The lead is an Ignition Reference Sensor and is used to detect knock in the engine. The car would most likely run fine without it fitted but like so many thing that people think aren't important, VW put it there for a reason!

 

Fitting it is a pain in the backside. Genuine VW leads (and most good quality pattern ones) allow you to unscrew the plug at the distributor end so you can slip the sensor loop over the lead.. lots of cheap pattern leads don't allow you to do this. If nothing else, worth ordering lead #4 (I think you can buy them seperately) from VW so that you can get the lead fitted.

 

I went through a load of aggro on my last 16v trying to find non-genuine leads which allowed you to fit this loop - did eventually find one AND forked out a ridiculous amount of money for a new reference sensor.

[bmwcompact 10]

There are 2 knock sensors on the front of the 9A block.

[james153 0]

Vw list the part as a camshaft sensor. the engine will run fine without it in principle as it has mechanical ignition timing, however the auto advance/retard will not work properly. so you wont notice any running problems, just a tad retarded ignition at high revs.

Hope this is of help

[RW1 0]

Its known as G4 - Firing Point Sender.

And it must be fitted the right way round. Tabs facing the Distributor.

 

If fitted in the wrong position, defective, is open circuit, ignition lead loose or igniton spark missing, it will generate fault code 00514.

The only check is that it lines out as 2 ohms max. This is done on the ECU pins 27 (Green wire) & 29 (Red wire) to include the wire resistance. Also check the Black wire (sheilding) goes to earth.

 

.

[Purplebaghera 0]

Hi. If anybody wanted an upgrade on their leads , for the 16v, if you buy the Blue Ignitors set from C&R Enterprises it comes with the sensor already fitted and also a new guide and a plug lead puller for each plug,does cost £126 pound though, but was qouted £100 years ago from dealer without sensor or guide so not too bad . specially after screwing up two sets from GSF tryng to get the thing on ;) Vince.

[mmacneill123 0]

This seems to come up on an pretty much yearly basis! The lead is an Ignition Reference Sensor and is used to detect knock in the engine. The car would most likely run fine without it fitted but like so many thing that people think aren't important, VW put it there for a reason!

 

Fitting it is a pain in the backside. Genuine VW leads (and most good quality pattern ones) allow you to unscrew the plug at the distributor end so you can slip the sensor loop over the lead.. lots of cheap pattern leads don't allow you to do this. If nothing else, worth ordering lead #4 (I think you can buy them seperately) from VW so that you can get the lead fitted.

 

I went through a load of aggro on my last 16v trying to find non-genuine leads which allowed you to fit this loop - did eventually find one AND forked out a ridiculous amount of money for a new reference sensor.

 

Cheers Jim et al, i have noticed a slight retard on heavy acceleration and as i have the GSF plug set i assume i am 'shafted' (no pun intended). Was a pain going to VW last week looking for other Rado parts 'dropped out without a replacement', might as well as had a robot sitting there... Will see if i fair any better just trying for a single lead :-)

 

Where did you get your lead from Jim? Cheers