fordrsrickc

iTrader: (5)

I was driving down the road today when I noticed the speedo stopped working and on came the engine light. But then the speedo kept coming on and off intermittently and the CEL has gone off and now works ok. I want to cure the fault before it happens again, but don't know what is wrong, is it something on the gearbox side or binnacle side hope it doesn't mean a problem with my gearbox as it's a DCCD 2003 STI. Does it have electronic sender for the speed and will my ecu need a reset after I have fixed the fault. When I find out how to fix that is! Any help will be appreciated thanks guys

scooby-tc

iTrader: (2)

sounds like a speed sensor issue.Only ever noticed it on early pre facelift classics where the speedo had become disconnected from either the cluster or gearbox.Never heard of it on a scoob after 1998. Might be worth getting the fault code read to give you a better idea of whats causing the CEL

Splitpin

There isn't a huge amount of point reading the fault codes when, as you already say Scooby-tc, there's only one thing this is likely to be - and only one error code likely to show up.

Fordsrick, as has been said, the problem is either the speed sensor itself, or a fault in the wiring harness between it and the ECU. The annoying thing is that intermittent failures are the worst ones to diagnose, because right now, everything will probably check out just fine.

It does have an electronic sender - sticks out of the offside of the gearbox about level with the engine bay back bulkhead. Then runs up through the 'box loom and into the main bay harness. Worth having a good look at all the connections, unplugging, checking for water ingress/corrosion/damaged cabling, but until/unless it happens again, it might be difficult to pin down the cause.

And no there's no need to reset the ECU after fixing it. The fault code will remain in the historic memory but that's not a problem.

fordrsrickc

iTrader: (5)

All sorted thanks for the advice I cleaned the electrical connections and one had blue chalky rusty stuff on and wire brushed it and alls well so far. Cheers