Jetronic Relay

[Southern75]

Hi all,

Just wondering if there is anyway of overhauling the jetronic relay in the 75/90 v6

My 75 has developed the habit of stopping in the most inconvenient spots e.g. Sydney Harbour Tunnel, Eastern Distributor and a number of major Sydney Intersections.

I know that this problem is occurring due to the jetronic relay having a hissey fit ... apparently the way it is stopping indicates its the injector side of the relay.

I have dissasembled the relay and resoldered all joints and cleaned up the relay contacts both internal and external, however the solenoid on the injector side still feels sticky or excessively magnetic.

I was going to buy a new unit, however they seem impossible to get ... second hand ... similar story.

The question i ask is ... can the solendoid be purchased separately so i can solder a new one to the pcb?

Secondly ... can i solder in the guts of a cheaper relay so as to overcome this sticking?

Thirdly ... is there a generic option that can replace this expensive and rare bosch unit?

This is also posted at:

http://www.alfaclubvic.org.au/component/option,com_smf/Itemid,68/action,post/board,10.0/

[dfrye]

Hi Matthew, I realise this is an old thread, but would be interested to hear what your eventual solution was.

I have gone through the same problems with random v6 engine cutouts only to find no power at the fuel pump. With the AFM flap open and ignition on - nothing. I have tried swapping the AFM (in case the microswitch was bad) - no difference. New fuel pump - no difference. Second hand replacement fuel pump relay (the double item) made the car run but I had a random cutout a couple of days later. It also appears to be heat related - once it decides to cut out there is absolutely no way in hell it will start again for about 15 minutes. After that it often fires first attempt.

Now I have a manual fuel pump switch under the steering wheel and have just gotten used to switching the fuel on and off manually.

I am starting to wonder if a problem with the pre-pump - am assuming the relay powers both the pumps.

Just interested in what your resolution might have been.

//dean

[david sammartino]

i have a good second hand relay off a running car if you are interested. pm me

[dfrye]

But I replaced that prick of a thing. I thought it just took the signal from the AFM flap as input? You've given me an idea though - maybe the relay ground is the problem not the relay itself. Will check.

cheers,
//dean

[Southern75]

Hi guys,

Thanks for the reply ... i got my hands on a brand new as they are still made but hideously expensive ... bit over 200 i think.

What you guys seem to be presuming that it was in relation to the fuel pump... this was not the case.

In fact it was the injector pulse side of the relay that was sticking which caused everything to stop without warning ... my fuel pump i can hear so i know it was still working.

I still have the relay and have tried the cleaning option, the better earthing option and so on ...

I even went through and de and resoldered the existing joints and it would improve the situation albeit not a great deal.

I do firmly believe that the relay mechanismes themselves are similar if not identical to what is in more basic relays bar the back that they are attached to a PCB to ensure that they are synchronised.
Unfortunately Bosch does not give you specication on the realys other than the fact of what is and is not available.