Reroute Engine Wiring Harness?
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Reroute Engine Wiring Harness?
I am curious whether anyone has rerouted the front engine wiring harness in an S4/GT. The original routing requiring that the harness be removed to change the timing belt seems like a second-best idea, but given the extremely limited clearances everywhere in the engine compartment, any changes that might seem to make sense might instead create new problems.
The front of the engine is pretty much stripped as I am in the middle of deconstructing everything related to timing belt/seals/etc. replacement, and am nowhere close to putting anything back together, but I like to obsess in advance about these kinds of things...
Thanks,
Bob
The front of the engine is pretty much stripped as I am in the middle of deconstructing everything related to timing belt/seals/etc. replacement, and am nowhere close to putting anything back together, but I like to obsess in advance about these kinds of things...
Thanks,
Bob
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From: Oman
Bob,
A year ago I discovered my 14 pin plug had wires entering it in an appalling condition. I had to replace about half of them to include the oil pressure sender cables, the sump oil level, the voltage lead from the alternator and the a/c solenoid. As I did not want to risk disturbing the other cables in case they were below par, I decided to remove the rock hard shrink sleeve back to where the loom disappears under the cam cover, ran the residual cores through a small conduit on the original route and for the cores listed I ran them in a separate conduit running from the oil sender area under the engine, then across the top of the aluminium under tray and then back up inner fender wall and then up to the 14 pin connector where they rejoined with the rest of the loom. It seems to work OK.
I hope to replace the entire loom soon and will probably revert to the original layout but I see nothing wrong with the partial cable route I used.
Rgds
Fred
A year ago I discovered my 14 pin plug had wires entering it in an appalling condition. I had to replace about half of them to include the oil pressure sender cables, the sump oil level, the voltage lead from the alternator and the a/c solenoid. As I did not want to risk disturbing the other cables in case they were below par, I decided to remove the rock hard shrink sleeve back to where the loom disappears under the cam cover, ran the residual cores through a small conduit on the original route and for the cores listed I ran them in a separate conduit running from the oil sender area under the engine, then across the top of the aluminium under tray and then back up inner fender wall and then up to the 14 pin connector where they rejoined with the rest of the loom. It seems to work OK.
I hope to replace the entire loom soon and will probably revert to the original layout but I see nothing wrong with the partial cable route I used.
Rgds
Fred
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From: Bloomfield, MI
The routing across the engines front due to the Fan change and PVC/Tank vent tubes on the S4, changed from on top of the water pump to going across the center cover along w/ the four ignition wires.
Rewiring is always a give and take, wires are usually kept short due to weight and cost on a car, changing from stock is not an issue in this case unless you sell the car and somone else has to figure out what you did
Rewiring is always a give and take, wires are usually kept short due to weight and cost on a car, changing from stock is not an issue in this case unless you sell the car and somone else has to figure out what you did
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I looked carefully at routing options while trying to identify places where charging & primary current was being lost. In the original routing, the only places where the harness ran close to exhaust include heat shielding. The logical alternative is to route primary cables through the crossmember and directly up to the CE panel. The sensing and switching cable routing is a separate matter, could be part of the primary wiring, but there are some connections on the front of the engine (AC wiring springs to mind) that still need o be managed. Is it worth an extensive re-route that really takes the same harness and flips it around to go bottom-rear instead of top-front routing.
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I wouldn't spend time re-engineering this harness that gets disconnected once every 5+ years for the timing belt project. In the total scope of that project, three bolts and a screw to free the harness and get it out of the way drop this part of the project down into the noise somewhere. I use some re-useable ball-type cable ties to hold the wiring to the crossbar during surgery. Maybe I need a bigger channel-type crossbar, and I could just stuff the wiring up inside permanently. No -- It's a lot cooler there across the front where the factory put it.
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I wouldn't spend time re-engineering this harness that gets disconnected once every 5+ years for the timing belt project. In the total scope of that project, three bolts and a screw to free the harness and get it out of the way drop this part of the project down into the noise somewhere. I use some re-useable ball-type cable ties to hold the wiring to the crossbar during surgery. Maybe I need a bigger channel-type crossbar, and I could just stuff the wiring up inside permanently. No -- It's a lot cooler there across the front where the factory put it.
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Thanks for the replies. I will likely not reroute the harness too much potential for the creation of some other problem that I won't realize until all of the rest of the bits and pieces have been reattached....
Bob
Bob
