Fallout from Area 52 RR Day

[Erni902]

Right well although a good day was had by all there were a few things that were discovered at yesterdays meet.

The fallout of yesterdays discoveries for me is a weird one. My speedo had stopped working! replaced the speedo converter and still not working. Car tried to escape the dyno due to the ecu signal output wire being cut and not attached. Also causing pops and bangs when on WOT in full auto. (not good).

Had a play and got it sorted by splicing it onto the MPH output signal from the speedo converter.

Speedo still not working though.

Swapped clocks, speedo still not working. (Everything else on the clocks works just the speedo that doesnt, same on both).

Anybody have any ideas what my issue could be? Please note:

1. Speedo converter swapped out
2. Clocks swapped out

Now I was starting to think about gearbox speed sensor however if this had gone then surely it would have the same affect on the dyno run and WOT as the speed signal wire being cut due to no speed signal. Am I right in thinking this or would everything act as normal apart from the speedo.

The speedo converter must be functioning correctly, receiving the speed signal and outputting the new signal as when the ecu signal wire was spliced to this the previous issues disappeared.

Any halp much appreciated

[exevoowner]

Did your speedo work on way to area52 ?

[swinks]

Speed signal wire to ecu (which I understand been cut) is reference only. Main function is to enforce "speed limit" of 112mph. Many dealers and private importers did simply cut that wire hence rid off annoying speed limit barrier. Other than that it won't affect vehicle.
Speedo dash is taking signal from gearbox speed sensor, that is were I will look for problems first.
Having pops and bangs indicate unburnt fuel getting to exhaust. I'd rather to consider look at settings of tps vs. ips. If both settings are are not maching each other ecu will fire injectors although throttle is closed and no spark produced. Well, don't know how to properly explain, but for peace of mind I'd follow whole procedure of setting ips and tps (don't mess with sas screw!).

[Erni902]

Did your speedo work on way to area52 ?

No hasn't worked for months lol just not had a chance to sort it out.



Speedo dash is taking signal from gearbox speed sensor, that is were I will look for problems first.
Having pops and bangs indicate unburnt fuel getting to exhaust. I'd rather to consider look at settings of tps vs. ips. If both settings are are not maching each other ecu will fire injectors although throttle is closed and no spark produced. Well, don't know how to properly explain, but for peace of mind I'd follow whole procedure of setting ips and tps (don't mess with sas screw!).

I shouldve mentioned Tomasz that the pops and bangs were those imitating anti-lag that Jason configured on my ecu for me in the past. The effect was that on WOT in auto only not tip (the weird bit) the ecu would initiate the imitation anti-lag just as it would if at a standstill. I assume the ecu must use this same signal as the reference when setup to 'pop n bang' when under 5mph (or 10mph i cant remember which). I say this because once we spliced the reference signal wire to the mph output the 'pops n bangs' stopped. I assume the same can be said for the AYC and TCL aswell because both these systems acted normally after the ecu actually had a signal. Although this is just a reference signal it seems its slightly more important than I realised as all the issues I had yesterday stemmed from this being disconnected.

TBH this was quite a pointless post as I thought soon after posting it that if the signal is making it to the ecu then the speed sensor is operating fine, the circuit up to the converter is working fine, the converter is outputting a signal (whether kph or mph its outputting something) and the circuit back to the ecu is working fine.

If the converter is outputting a signal to the ecu but not either speedo then the obvious issue is the circuit between the converter and the rear of the clocks.

Ripped it all apart again and pulled the connector out thats attached to the rear of the dash, hey presto, whoever installed the original converter has used crimp connectors and the mph output wire had come loose. Turns out it was even crimped in place so I was able to use the same connector to secure it again.

Re-seated the connector in the dash and placed clocks back in and hey presto :) I now have a working speedo again.

Cant believe I didnt think of this before, thats what you get for looking too deeply into something /pan

Many thanks to everybody for their input, suggestions and help. At least I suppose this thread can go to help someone else in the future if they have an issue with their speedo lol

[exevoowner]

That was going to be my next idea to say try plug to clocks as i know when when i changed mine and test drove it i had too push hard on clocks to make them work fine it seams as tho the plugs are a it funny to relocate

[swinks]

IIRC that's launch control implemented in Kenneth's rom which kicks in on WOT over 4k revs taking speed signal as reference when vehicle is stationary. Having wire cut, it will kick in whilst wot when driving. Got that problem after my 1st flash Kenn's rom, till realized issue and disabled feature.