Piston Broke

Whats the symptoms or tests to check the fuel ECU on an RS turbo please as im sure mine is KO. Any help would be brilliant thanks

Piston Broke

Anyone help, please !!!!!!!!!!!!!!!

mk2grp1

hi I would open the box and examine for melts or popped components,
and give it a sniff test,
if I didn`t have 5 in my spares pile to try
also I would consider buying another always plenty on ebay,
they very rarely play up, more likely is one of the sensors it reads and controls,
damaged ecu black box can occur in a paintshop oven or welding,,
have you attempted to explain your symptoms

Piston Broke

Hi mate, im a mechanic so half half an idea where to look but this has got me, i put the rs engine from my rotton shell into a mint one, now starts ace and idles spot on but when i rev it i have a mass over fuel and missfire like anti lag (im on MFI by the way)

Turbosystems

iTrader: (5)

The black box controls cold start enrichment, over run fuel shut off, on boost enrichment and full throttle enrichment only
You have more than likely plugged some wires on the wrong sensors most common for people to get wrong is the auxiliary air valve and coolant temp sensor
The blue injector needs unplugging and checking it doesn't leak
For all the input data the black box recieves it only controls the electro magnetic fuel pressure actuator on the side of the metering distribution head
Disconnect the 2 wire connector when running rev it see if the fault is cured
Start there
These cars require an expert to fix them the system is complex

Piston Broke

Yep traced all the wiring from sensors to ECU multi plug and thats all spot on, wouldnt say there hard there easy wiring wise just a timing/fueling type issue that i carnt fault mechanical only suspect is the ECU, i tryed the pressure actuator on the side it cut out the first time now does nothing when unplugging it, will re test the wires to the pins on the ECU to triple check and check sensors one more time and get back as soon as i have tried that thanks for your help so far

Turbosystems

iTrader: (5)

Have you done as I suggested and disconnected the actuator when running
don't waste time rechecking all pin outs

Piston Broke

Yes like i say i did do that the other night and it cut the engine, now reconnected when i run the engine and try unplugging it again nothing happens dont stall or make any difference ! odd

Piston Broke

I had chopped the loom you see thats why i checked the pin layout, but all good, the other thing i could think is if say on one plug would it make any difference if the wires were the wrong way on the same sensor as its a resistance its looking for right ?

Turbosystems

iTrader: (5)

like I said the system is complex, I explained in my previous post what the system basically does
when the engine reaches around 50 degrees C no further warm up enrichment is required so if the black box is working correctly it will have no affect to the fuelling
Unplugging the actuator should have no affect on the engines running in this state and the cars basic fuelling should be set with the car in this condition

Turbosystems

iTrader: (5)

correct for thermistor type sensors
The auxiliary air valve is powered by the fuel pump relay at battery voltage as I mentioned earlier it is common for people to plug this wire onto the CTS which is a thermistor this will destroy the CTS

Piston Broke

cool thanks for your time, i program modern ECUs so no daft to them but more laptop tune that pre set chips and resistance. Right so the black box in sense is working as i guess cold when i first unplugged it and warmer afterwards so in a sence the black box only works when the engine coolant is below the 50 c. I thought the yellow coolant kept working, is that just to provide a earth relay switch to power the black box to re enable the enrichment i guess from the ECU

Piston Broke

I know which plug is the CTS from the prob and know that plug is on to the CTS, so the CTS have a live to it then ??

Piston Broke

so in the post before the CTS yellow is the power supply for the KE fuel ecu

Turbosystems

iTrader: (5)

NO
So you work with the modern plug and play self diagnostic engine management systems then
The black box continues to read the CTS but does not enrich the fueling whilst the engine is running and at 50 C +
If you turn the engine off and attempt to restart it it will activate hot start enrichment utilising act cts rpm air flap position

Piston Broke

Why end ? im learning from your advise ?

Turbosystems

iTrader: (5)

You need to reassess the car using the info I have given so far

Piston Broke

I know from what you have told me the fuel ECU is working now, thanks for that info its a big help, shows i need to look in other areas now even check the timing and C0 setup etc things like that.

Self diagnostic. no there just crap they dont tell you the problem they just guess to be fair to them as only relay a train crash effect i guess lol, prefer when i worked on fast jets in the RAF but them days are gone a long time ago lol thats why talking to you lets people learn your skill/know how

Piston Broke

But yes will try unplugging the pressure on the metering while it has revs on as advised and get back to you thanks again for your time much appreciate it, what do you do i guess tune these lol? !!!!!!!!

Piston Broke

Are you Tony from ART Motor Engineers in Wakefield ??

Turbosystems

iTrader: (5)

Who
Check out my user name

Piston Broke

Sorry just thought you were him by the sound of your know how and if that was the case going to drop it off to be sorted as not far from me, will be back at the garage tomorrow as have had to have time away dude to family but wil try what you advised thanks

Piston Broke

Right Turbosystems, i started the car and give it some revs with missfire, BUT Unplugging the actuator the car reved spot on with no miss fire, this was all while the engine was cold. So yes with it unplugged it ran spot on and as soon as went back in the missifre on revs came back, what does this mean ? a fault with the CTS .............. thanks again for your time with this

Turbosystems

iTrader: (5)

Are the sensors plugged in correctly
Have they been plugged on the wrong ones, if this is case you may well have destroyed the CTS
Is the cts connected to the ecu check the connector
If all is well unplug the cts and bridge it out the ecu will interpret this as 80 C and do the run test again with actuator plugged in
open circuit the ecu will interpret that as -55C

Piston Broke

Thanks for the reply, right all the sensors are plugged correct, the pin layout to the multi plug to sensor all feed correct and have a good feed, just removed the CTS and have done a resistance check and the sensor is dead. I have ordered a new one but been my look there is a wait on them so as soon as it comes will fit/try and update as thats looking to be the fault. When setting the ignition timing on these then and listening to what you have said i take it you up plug the actuator and crimp the ECU MAP hose to get a pure mechanical reading if that makes sence. Thanks again mate

Turbosystems

iTrader: (5)

you disconnect the vac hose from the plenum so that the map sensor records atmospheric pressure do not crimp it ,you unplug the actuator to set the static fuel curve

Piston Broke

Ok thanks, makes sence. Where/how did you learn so much about these as you are very clued up on them. Nice to get straight answers about the ECU system and how they work as alot seem to guess !

Piston Broke

Right a update, the BRAND NEW CTS came today and the results were spot on, no cold misfire on rev's. and also revs brilliant until its been running for 30 mins + an driven and read hot then it misfires, pretty much all the time. Take it this is more than likely to be a set-up needed ie C0 and timing ? thanks

Piston Broke

By the way I never knew as daft as it sounds that you were THE turbosystems so knowing that I owe you a bigger thanks Tony. Do you still tune now or just choose what you want to tinker with ?

Piston Broke

Car is sorted i went back to simple checks, i removed the injectors and found them to be the main reason for the faults, new injectors in from Bosch £26 each and sorted and spot on ! simple things are the best, just 2 faults but all running thanks for your time Tony.