Wiring and connection issues are a well known problem that at some time will afflict all zeds in some way.

 

The engine wiring loom has lots of low voltage signal cables that are protected from interference by the use of shielding, this is a good idea when new but can become problematic especially on looms that have been moved many times.

 

So a case in point, the pictures below show the loom section which serves the drivers side O2 sensor connector, the larger loom splits off and leaves the O2 sensor cable ( 3 core) on its own, however over the years the cable becomes less flexible and the point where the loom splits up to the different sensors a degree of damaging flexing occurs when the engine is running.

 

This eventually can lead to the shielding and the cable its supposed to be protecting coming into contact with each other. The pictures show the process of splicing the outer cables back to get the the problem because until this is done the problem is hidden, previous knowlege and correct fault diagnosis is essential because hacking away at the loom to find faults without knowing where the actual problem is will soon result in needing a new loom!!

 

So back to the problem below, the engine was not happy at all, it had a heavy smell of fuel and a low level murmor, and very errant tick over, no amount of checking by other garages had identified the actual problem.

 

Problem is, ConZult and similar systems cannot identfy the exact problem for the less experienced, but by using the information it can give and added to what it was`nt telling was the key to this.

 

Any shield fault in the zx will cause almost baffling test results and can be quite a battle to track down, shield faults generally causes feedback issues through all of the other sensors via the ecu as they use a common earth braid.

 

Once identfied the fault was easy to clear by re-insulation the signal cable and also moving the shield braid clear of the cable, once done the throttle balance needed adjusting as did the base idle and resetting of the self learn, a test drive and log file showed all working again and hopefully for the owner a little less heavy on fuel.

 

 

Jeff TT

 

 

 

 

 

 

Nice heads up Jeff..thanks for your time.

Agreed Bri, vey helpful Jeff.

 

To add I've also seen what looks like perfectly good wiring but when cut open, the wire has been green with corrosion.

It always amazes me how you can strip the insulation back on a cable connector and the wire conductor is discloured for a good length up the cable, indicator bulb loom is a classic for this.

 

Jeff

Just goes to show how far moisture can travel up the loom. I put a little blob of liquid insulsator tape on the back of my connections. Probably not going to stop it but makes me feel better.

Nice fault tech post Jeff:thumbup1:

Nice fault tech post Jeff:thumbup1:

 

Seconded - it's good to see the return of your techie threads Jeff!!

 

Richard:sorcerer: