Can anyone help me location where the diode resistor pack is located on 1981 Triumph tr8 fuel injection vehicle. If you have a picture of what it looks like that would be great. Thanks for your help

If you are asking about the resistor back for the injector drivers, it is on the firewall on the (US) passenger side. The bracket they mount to is part of the battery shelf (which is where the vapor recovery canisters mount on a TR8).

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Darrell Walker
66 TR4A IRS-SC CTC67956L
81 TR8 SATPZ458XBA406206
Vancouver, WA, USA

I think this is it.

Hi, thanks but that's not it. It shows on the diagram that it should be behind glove box new the combine relay but if just don't see it.

What is the build date of your car? From the schematics I have, only the "1981 1/2" cars would have it, and they would have two discrete relays, not the combo relay. My car has a May 81 build date, and has the combo relay. I don't know if the "1981 1/2" would also have the push button clock or not.

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Darrell Walker
66 TR4A IRS-SC CTC67956L
81 TR8 SATPZ458XBA406206
Vancouver, WA, USA

Thanks for your assistance. It has a Aug of 81 build date and it does have a push button on the clock. Can you send me what schematic you have please.

Thanks

This is the schematic that use:

http://www.team.net/TR8/tr8cca/wedgelab/other/schematics/TR8_schematics.pdf

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Darrell Walker
66 TR4A IRS-SC CTC67956L
81 TR8 SATPZ458XBA406206
Vancouver, WA, USA

Thanks for the help I will need to do some work after looking at the information

Thanks

What is the function of the diode resistor pack? What part are you referring to exactly?

Apparently 81 1/2 tr8 with fuel injection came with a diode pack behind the glove box area. I have a fuel relay issue and it looks like power goes through the diode pack to power up relay so I trying to figure this thing out to get my vehicle running

You are correct. The 81-1/2 eliminated the combo relay, and replaced it with two separate relays and a pack of diodes and resistors. The schematic shows it as a separate module, but I suppose it could be built into the relay sockets somehow. I was completely unsuccessful trying to find any additional information on its location or appearance.

I would show you a picture of its location on my car, but my fuel injection system uses carburetors.

Vance

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1980 Platinum Metallic TR8, navy blue interior
Bare metal respray, Crower cam, raised compression
ported heads, modified Zenith carbs, 0.060" overbore

Is it possible to follow the yellow/green wire from the upper relay? Its location is probably very close to the relay. Even if you cannot find it you can disconnect the wire ends connected to the other components and test the function.



Edited 1 time(s). Last edit at 2017-12-13 12:39 PM by kansanbrit.

Hi, I hope that you might help me again. I found a wire that is spiced into the first purple line from the ballast resistor unit on firewall for the fuel injectors and that wire goes back to the w/y wire coming from the starter. When I remove that wire the vehicle will not start and when connected it runs. Its bypassing a problem do you have any ideas of where or what they are bypassing.

Thanks
James

Purple is hot at all times. It sounds as if the coil ballast has 12v on it at all times, even with ignition off. W/Y should supply 12v during cranking only for max spark. Do you have 12v on ballast white wire when ignition is on? Is the coil original?