Thread: TD5 four cylinder engine...

Time to replace injector harness

I'd lay money on your problem being with the connection on number 5 injector.
Remove the rocker cover (about 12 to 15 bolts) remove the injector harness and check if there is any oil sitting around any of the injector connections. After noticing the oil sitting in number 5, give all the connections a spray with WD40 or similar and a blast with compressed air to remove the oil & WD40. Put everything back together and drive your 180km back to work with 5 cylinders operating and a smile on your face.

It''s happened a couple of times to me and I've always done as above. I'm still using the 17 year old harness which has only been cleaned and has not been modified in any way.

A similar thread here Running rough in Ceduna - any ideas?

Good luck. Let us know how you go.

How was your 180km trip back to work Ian? Did you get that 5th cylinder to behave?

When I changed my injection harness I was surprised that there were no seals on the original harness or with the new harness.

The injector plugs on a V8 which are the same as the TD5 ones have a small square nylon seal that sits up in the injector plug and seals it against water or whatever.

Of course the V8 plugs are outside the engine.

My new(ish) harness has now been in for several years with no problems but I sometimes wonder if seals would reduce oil getting into the harness.

BTW IMHO the problem is really not the oil into harness but the sealing of the harness plug where it plugs into the main harness on the front of the rocker cover.

I reconditioned my old harness and resealed the plug with Araldite when I replaced the harness but I have never needed to refit the old harness. I actually cut each wire then sealed each wire with solder before crimping and leaving the inner end open so as to speak, hoping that any oil would then have no access to the plug. Wasted time I guess but it should be dry now as it has been hanging on the wall for years.
Regards PhilipA

If you replace the harness there are some good guides in old threads about sealing it to stop oil entering/traveling through. From my experience this works well with my harness having held up for 11 years until some of the plastic of the round connector failed due to head/age/vibrations etc.