Please, has anyone succeeded in removing (for access) that part of the wiring harness behind their engine? I have removed everything I can find including the two bolts that hold it in place and the hidden MAP Sensor Connector, but it appears to be attached to other (inaccessible) harnesses beneath it? I do not know what I am doing back there and I don't want to pull on anything unnecessarily!

 

OMG. You now have 3 threads for the same fault . I'm sure that's not even allowed .
I can"t believe your delving in there before trying your new corect component .
Which proves your not listning !
5v supply is correct . So what are you trying to prove .
the 5v on the sence wire is an obvious fault with sensor .
It sends a voltage back to the ECM to determine fuel pressure . .
5v= Too high pressure
3v=max pressure
less than 3v=less pressure .so you need a sensor that sends the correct voltage back .
That's not up to the cars wiring .the wiring just passes on the info

 

My apologies Datsports - I thought that asking how to access the back of my harness was a different subject to an engine running rich or a faulty FRP Sensor and therefore would be better in a new post? I did not realise this was against the rules? I searched the Forum for 'Wiring Harness' before posting and came up with nothing relevant? Should I receive replies, then (in the future) someone else with a Wiring Harness problem will find the post; I cannot imagine them searching 'Engine Running Rich' or 'FRP Sensor' for a wiring harness problem?

Of course you are absolutely right! No, I'm not considering removing my Harness just yet. When I first had the FRP Sensor Pinpoint Test problems, I tried then (unsuccessfully) to bring that part of the Harness which is behind my engine up into view to look for any damage I may have caused when removing/refitting my Manifold. I am now just doing my research in case it becomes necessary - I intend to fit the genuine FoMoCo Sensor which will arrive here on Thursday and then just try the engine before I disturb anything else!

The 5v I have between the Signal wire and Ground is found (as per the relevant Pinpoint Test) with the ECU connected and the ignition on, but with the FRP sensor disconnected, so I was thinking that whether or not the FRP sensor is faulty is irrelevant - As far as the wiring is concerned, the Sensor does not exist?

 

Please find attached photo showing the disgusting state of the Engine Management part of my wiring harness! I currently have much of this harness disconnected (including the ECU Connector) as a result of a different problem I have been having, so I plan to try to tidy it up a little while I am waiting for a part and have the opportunity; I have bought the plastic split tubing and a couple of rolls of heat-proof tape. I cannot buy (or afford to buy) the knowledge! Surely, my Injector and Coil wiring, so close to the engine should be better protected from heat than they are?

I have also attached Sensor location diagrams. How do I disconnect Sensors 16, 17 & 18 from the ‘Front View’? Do I have to remove the Radiator? Perhaps should I bother? After all, there shouldn’t be that much heat immediately behind my radiator? (apologies for sarcasm). How about Sensor numbered 6 (Crankshaft Position Sensor, situated behind our engines); from the attached Sensors ‘Side View’? Number 6 has a red ‘tab’ that can be slid along it, but (mine) does not appear to achieve anything? How do I disconnect it? I imagine the heat behind our engines is intense. Perhaps that’s why the only bit of real heat-proofing is for the Brake Booster Pipe, tucked in behind there?



Forum, I only want to use this opportunity to improve my Harness as best I can (without dismantling my car) – Any suggestions as to how far I should go from Members with prior experience of playing with fire will be most welcomed!
Even if that suggestion is ‘Leave it, you idiot’!!

 

i'm going to say it because no one else has .
it looks fine to me , all the conduit is in tact,
the tape's still on
no bare wire's .
and it goes under a plastic cover . so cosmetics is taken care of .
i think you are cruising down the right path were tampering with the best intentions , may bite you in the ***.
yes wires get brittle with heat and age . i think best to only do what ever is necessary . and other wise leave it alone .
don't bend or move them .
you can also replace/repair wires/plugs ,
and buy looms quite cheep from the forum sponsor's and others like ebay and so on .
so not the end of the world if that time comes ,
but yours does not look to need it .

 

Thanks Datsports; that is almost as reassuring as your previous post!

I was going to put split-plastic tubing (or whatever it is called) on all of my branch-offs to Coil & Injector wiring and then seal it with heat-resistant tape while I had it all disconnected? Is that not correct? Whatever was on there originally appears (to me) to have crumbled away? Or do those branch offs not need plastic protectors, just tape? I don't know what is normal and correct because I have never seen anyone else's X350 wiring?
I do want to improve the protection - I already have a EGR Valve connector where I have had to solder an individual connector back on to its wire, plug it in separately, then push the connector back in over the top of it - The connector innards around this particular wire had disintegrated!

I do understand your caution when disconnecting things (perhaps) unnecessarily - My TB Motor Connector also looks dodgy!