2.8i Coil Wiring

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gaz7952
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2.8i Coil Wiring

Post by gaz7952 »

Hi All,

Im new to the forum and am trying to get my 2.8 going after a few years in storage. I think I have a dodgy coil which I am looking to replace however there are a few things concerning me with regards to the coil type required.

With the ignition in position 2 I get 12v at the coil

The ballast wire is still in place and I have 12v at both ends of the ballast wire (which seems strange) with the ignition in position 2 (ignition lights on) I have no volts at the coil with the ballast dis-connected. The ballast wire resistance is 1.6 Ohms

All of the wiring loom looks intact and the wiring to the starter is the same as the Haynes manual.

Is it correct that I need to buy a 12v coil rather than a ballast coil which runs on 9v I cannot check voltage at the coil when running as it won’t run.

For clarity the car is a late model registered in 1988.

Any help greatly appreciated.

Cheers Gaz
STEVEW
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Re: 2.8i Coil Wiring

Post by STEVEW »

Hello gaz7952

I’ve just re-read the info about coils in the Ford Capri Manual – re-printed copy to get some specs for you to test your coil.

The primary resistance of the coil should be, 0.75 to 0.85 ohms.
The secondary resistance: 5000 to 6000 ohms
These are the figures given for a 2.8i.

As a comparison, we have a 2.3 Cologne motor and the figures are:
Primary resistance – 0.95 to 1.6 ohms.
Secondary resistance – 5000 to 9300 ohms

I hope this is of use to you.

PS Why do you suspect a problem with the coil? Has someone changed it?
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Peter-S
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Re: 2.8i Coil Wiring

Post by Peter-S »

STEVEW wrote:
PS Why do you suspect a problem with the coil? Has someone changed it?
I was wondering the same. Seems to me that problems starting a laid up 2.8 seem more commonly to relate to the fuel system, such as a stuck plunger in the metering unit. Do you know for sure if it is electrical in your case Gaz?
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gaz7952
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Re: 2.8i Coil Wiring

Post by gaz7952 »

Thanks for the responses when I can get the thing going it runs like a V4 and misfires under load. As it has been stood on and off for approximately 12 years I thought I would eliminate the electrical system before I had a crack at the fuel system. It has fresh fuel and a new fuel filter.

I am just trying to do things step by step and tackle one thing at a time so was just trying to get a new coil and wasn’t sure if my ballast system was still in place hence my initial query about the required voltage as it seems unusual to have 12v at the start and end of the ballast wire.
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Noel
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Re: 2.8i Coil Wiring

Post by Noel »

Do a compression test too and make sure you haven't got any cylinders on the low side, which could suggest exhaust valve clearances too tight.
long layup could exacerbate poor valve sealing too.
If this happens you end up with "dead" cylinders and poor running.
STEVEW
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Re: 2.8i Coil Wiring

Post by STEVEW »

I agree that step by step is better than throwing money at it and unsuccessfully changing parts, although I think we’re all guilty of that at some time.

I now see why you went for the ignition system as misfiring under load usually points in that direction. Plus, of course, it is recommended to check the ignition system before pulling the fuel injection system apart.
I’m sure you’ve checked that both the LT and HT ignition circuits are secure but have you looked for teeth marks in the HT cables themselves? I’m not joking!
In Germany it’s a common problem that rodents like to chew on HT leads. (Probably because they don’t understand the difference between “wine gums” and “wire gums”.)
However, 12 years seems a long time for the car to stand so I also agree with “Peter-S”: the problem could be crud in the fuel system.

I am an amateur when it comes to car injection systems nevertheless, I would start with checking that the breather hole on the Fuel Accumulator is not blocked. The accumulator is located near the fuel tank and has two fuel pipes at one end. The breather hole should be at the other end.
I would then do a fuel flow check as per the Ford manual. This should indicate two possible problems: fuel pump flow weak and/or contaminated petrol.

Let me know how you get on.
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