Speedo sensor issue

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Cozzamozza
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Speedo sensor issue

Post by Cozzamozza » 09/10/17 23:14

Hi All,

First time posting, tried to search and have been googling for a day but not found what I need! Any help is appreciated. So I'm borrowing my dads MK2 1992 G-limited import, gleaming white, but the speedo (mph) hasn't worked for some time. I cannot confirm if it ever worked as a mph speedo or not. And it's rumoured there has been a gearbox change at some point.

Looking in the engine bay I've found some loose connections. One of which is at the top side of the gearbox, 3 pins (male), perhaps for cruise control models or?. I have a 2 pin (female) connector in the loom below the fuse box, which has been taped up, but can reach the 3 pin connector, or where I think the speed sensor should be from diagrams I've seen? And two misc connections I'm curious about!

Topside of gearbox, viewing from nearside
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Corroded bracket, does the bracket serve as an earth? This is by the fuse box
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2 pin connector by fuse box
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Two misc wires coming out of the loom by what I assume is the thermostat housing
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peteV6R5
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Re: Speedo sensor issue

Post by peteV6R5 » 09/10/17 23:56

top of gearbox is the top of the speedo drive. you need to connect the associate plug that must be free to it. electronic pulse driven speedo from REV2 onwards
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Cozzamozza
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Re: Speedo sensor issue

Post by Cozzamozza » 11/10/17 20:44

Ah good that is the sender then?

Any idea what each of the 3 pins do?

As my free connector only has 2. There's a chance the engine and loom were also changed..

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Re: Speedo sensor issue

Post by Gazza_DJ » 13/10/17 12:08

Are you sure it's an import? From the very limited view of the valve cover / exhaust manifold that looks like a 3SFE, which was never available in Japan - only Rev1 UK cars. Might be wrong, can't see much of the engine!
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Re: Speedo sensor issue

Post by jimi » 13/10/17 12:32

Was the FE speedo not cable driven?

EDIT
Checked the EPC and it appears they the same as the 3S-GE, Rev1 cable Rev2 onwards electric
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Re: Speedo sensor issue

Post by Gazza_DJ » 13/10/17 20:55

jimi wrote:
13/10/17 12:32
Was the FE speedo not cable driven?

EDIT
Checked the EPC and it appears they the same as the 3S-GE, Rev1 cable Rev2 onwards electric
The gearbox it would have been attached to from the factory would have been, OP has stated it may have had a gearbox change at some point as well. Look at the valve cover / plate though - that looks exactly like the FE one. Gen2 3SGE looks quite different.
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Cozzamozza
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Re: Speedo sensor issue

Post by Cozzamozza » 14/10/17 10:05

So there may have been an engine swap as well then!

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Re: Speedo sensor issue

Post by Gazza_DJ » 14/10/17 11:19

Post a photo of the engine bay to confirm.
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Re: Speedo sensor issue

Post by Cozzamozza » 16/10/17 19:22

The timing belt cover says your 3S-FE guess is spot on. This car..

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Re: Speedo sensor issue

Post by Gazza_DJ » 17/10/17 11:00

Strange swap to do that, a Rev2 G Limited would have had a 3SGE originally!
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Re: Speedo sensor issue

Post by jimi » 17/10/17 11:52

May have been cheap available replacement for a dead engine. I'm wondering if the car is really a rev1 (mechanically driven speedo) fitted with a later FE engine (electrically driven speedo) hence no matching plug for the gearbox sensor? Easy enough to find out when the car was built from the VIN number
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Re: Speedo sensor issue

Post by Cozzamozza » 18/10/17 22:42

Explains why it doesn't feel like the g-limited 160 odd bhp spec. Still very fun though.

The car smells like it's running rich also. Not the best example. I'll get the VIN and check it out. Reckon there's anything I can do if that's the case?

Or any recommendations for GPS speedos haha

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Re: Speedo sensor issue

Post by pbmr2 » 19/10/17 0:01

Take the speedo trim out (only a handfull of screws, no special tools) and check electric or cable.

Either fit the cable sender into the box and a cable back to the speedo if it's rev1 or run some wire to the speedo if it's electric. most odd.

replacement NA engines are very cheap, bought one with gearbox etc for under £200 this year and sold another 2 for under £200. All working examples.
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