E320 missing

[Sp!ke]

I think Mark300SL is saying he wouldnt pay that either but would make the loom himself instead @£30 odd.

 

[imadoofus]

There is an official repair kit available from Mercedes nowadays, so new loom not normally required.

I don't suppose you have a part number do you?

Having said which, my insulation is cracking where it plugs into the water pump anyway.

 

[imadoofus]

I would trade it in before I pay this. I must be in the minority here, but some of you guys must be really wealthy ?

If I get rid of the car, what do I replace it with?

Running an old car takes financial commitment.

Bear in mind that I don't have finance or loan repayments on this car, so when it runs well (as it usually does), it only costs me fuel. The odd bit of maintenance is inevitable.

 

[Mark300SL]

I don't suppose you have a part number do you?

Having said which, my insulation is cracking where it plugs into the water pump anyway.

A2025406081 (x3) is the part for the coilpack wiring and is an easy fit - Its all covered in my thread on P2/3

Check the coilpack and injector insulation because its almost certainly gone,
Get the loom tape undone and reinsulate everything that runs down the top of the engine in the harness carrier, and dont forget to do the MAF sensor too


Mark

 

[imadoofus]

I got a price from Mercedes of £545 + VAT, lead time about 5 days.

But I've decided to have a go at the DIY route anyway, because if it doesn't work, I can still buy the loom.

One thing I'm unsure about: Under the engine cover, the leads are encased in rubber. What do I replace it with? Is the fabric tape OK? Also, can I remove the plug caps from the leads, or do I need to cut the leads six inches away from the caps, and the resolder them after heatshrinking?

Hope that makes sense, and TIA

PJ

 

[Dieselman]

I got a price from Mercedes of £545 + VAT, lead time about 5 days.

Boom..Boom..

do I need to cut the leads six inches away from the caps, and the resolder them after heatshrinking?

Why not just seperate the leads in the loom then cut them near the bulkhead and slide heat-shrink over the existing insulation back down to the coil connectors.?

 

[imadoofus]

Boom..Boom..

Why not just seperate the leads in the loom then cut them near the bulkhead and slide heat-shrink over the existing insulation back down to the coil connectors.?

I will (I guess) need to remove the rubber sleeve from the "HT" leads under the top cover, because I won't be able to slide the heatshrink over each wire whilst it's inside the rubber, and even if I could, I wouldn't then be able to shrink the heatshrink.

So I assume I have to remove the rubber outer sleeve from those leads, and having done so what do I replace it with?

I can cut the wires near the bulkhead, but if I can get the plug cap off, surely it would be easier to work from that end.

 

[imadoofus]

Oh, and what size ID heatshrink do I need? I guess 1.5mm is enough.

5m length?

 

[Mark300SL]

I just removed the rubber block for the time being as I needed to cure the problem

I used replacement coilpack leads as mine we gone all the way into the plug that fits on the coilpack - therefore there was no way of insulating it all the way into the plug.
I literally just replaced all 3 coilpack leads and spliced them into the loom across the rear bulkhead where the existing loom was still in perfect condition

Its very hard to explain - but in my case the worst areas of insulation breakdown (read that as powdering!) was the coil pack connectors and the area immediately adjacent to the big rubber section that goes through the cam cover.


I will drop you a PM with my number as I could explain in a couple of minutes what would take hours to type out!

 

[imadoofus]

Thanks Mark

 

[janner]

You're not going to like this but I say bite the bullet and replace the loom.
There must be cheaper places than the dealer. (Maybe search an American forum and get one shipped?)
By the time you mess around soldering wires you might as well replace the lot. If you DIY you will need to use all the correct gauge/spec wires and if you don't change them all you risk having more problems in the future. Every time your car misses a beat or has the slightest problem you will be wondering if it was the wires in the loom that you didn't change. The ECU takes signals from lots of components and a short on any wire can give you grief.

 

[Mark300SL]

BTW - 1.5mm heatshrink does just fit - but its quite tight and as the insualtaion is cracked and broken it is actually very hard to slide over the poor areas of loom without it snagging

Just use 2.5mm - its a lot easier

Adrian - its just a case of reinsulating whats already there - I am 100% confident in my loom

 

[imadoofus]

I suspect you're right, Janner. Having had a conversation with Mark, I am at least going to take a look, and try the DIY route, for fun confused: ) if for no other reason.

I was assuming there'd be the odd bit of coloured insulation left in there to help me, but it seems there probably won't be. At that point, knowing myself as I do, I will probably admit defeat, and order the loom

PJ

 

[imadoofus]

Right, I've gone and had a look. As I said before, the insulation is cracked where the wires emerge from the plug on the waterpump housing. However, poking the insulation with a scalpel doesn't dislodge it.

I have cut away most of the fabric tape wrapping the cables in the tray running North-South along the top of the engine. The wires inside are perfect, and I mean perfect. I can't find any breaks in the insulation, and I can't cause it to break with my scalpel.

I know it's possible but is it likely that anything else could be causing the car to misfire? I replaced coil packs a year (5,000 miles) ago, and the ECU was rebuilt at the time. My MAS was replaced two years ago.

I don't want to rip the loom to bits (or to buy a new one) if there turns out to be a simpler/cheaper cause.

The fault code reader still gives nothing off port 8. Not even a single "OK" flash.

PJ

 

[grober]

Moving away from ignition if the wiring is OK could your misfire be caused by a malfunction in the 2 solenoids that switch your variable inlet flaps or by the inlet camshaft advance mechanism jamming?

 

[Mark300SL]

Have you checked the wiring where it enters the rubber block and under the coilpack cover ?

The wires to the coilpacks themselves are the most fragile as they get moved the most, and especially where it enters the block from the engine bay side - internally through the block itself they are reasonably well seperated from the other coilpacks even if not from each other, but the entry point is just a collection of 6 wires all bunched together with suspect insulation.

 

[imadoofus]

Moving away from ignition if the wiring is OK could your misfire be caused by a malfunction in the 2 solenoids that switch your variable inlet flaps or by the inlet camshaft advance mechanism jamming?

If you say it's possible, then it's possible How can I find out?

 

[imadoofus]

Have you checked the wiring where it enters the rubber block and under the coilpack cover ?

The wires to the coilpacks themselves are the most fragile as they get moved the most, and especially where it enters the block from the engine bay side - internally through the block itself they are reasonably well seperated from the other coilpacks even if not from each other, but the entry point is just a collection of 6 wires all bunched together with suspect insulation.

I can't see the 'rubber block' you mentioned. On my engine, the calbes under the top cover are rubber-sleeved. At the point the emerge fromt hat cover, they become fabric taped. At that point, everything is cable-tied down, and absolutely does not move. I am hoping that's a good thing, and is protecting the insulation on the individual wires.

Sadly, I suppose it means I will need to disturb them to replace the coilpack leads, but I can't find the rubber block.

 

[imadoofus]

This shows the general condition of the wires in the top cable tray:

And this shows the cables emerging from the engine cover, and disappearing into the bulkhead, and the fact that they are very securely cable-tied down. It doesn't show a rubber block.

 

[Mark300SL]

Top looks a lot better than mine did

The block the coilpack wires go through is the division of outside/inside the top of the cam cover and the engine bay