clubstylus

Having just got my ECU for my ' new ' engine (I was using Dunnell's spare till my new one was in stock !) this afternoon I thought I'd just plug it in and run the engine since it's not turned over for 4 weeks. Plus I'm supposed to be at NORTHAMPTON MOTORSPORT for the JPSCC inaugeral launch , sponsered by COMPLETE KIT CAR --- Next Saturday 1st Dec.

If anybody tells me again that throttle bodies are so great and the engine starts at the touch of a button NOT LIKE CARBS -- with which I never had a problem

You guessed it ---------------- no chance , it wont bloody start I've checked out all systems on the laptop and pulled the fuel pipe off at the fuel rail , plugs out , fired each one . Tested each injector , all click . Spent 10 mins on the phone with Dunnell about three times going through what it says on the laptop etc etc

He says there's no reason why it wont start then ---------- h'mmmmm Well maybe I'll just pour some petrol in the cylinders and throw a match at them

Well Rob,

Face it, you don't like electronics and electronics don't like you.

Werner Van Loock wrote:Well Rob,

Face it, you don't like electronics and electronics don't like you.

Spot on Werner

Serves you right for having such a small one Rob (I am talking about the battery)

hearbear wrote:Serves you right for having such a small one Rob (I am talking about the battery)

Well you would have been right but since meeting you at Llandow I've fitted a VARLEY RED TOP 25 which is 680 cranking amps and it wizzes it round like a top . Unfortunately the old addage of --- if it's got spark and fuel -- it has to start Doesn't hold true with bloody ECU's , plus Werner's right , I don't understand electronics

I had a similar problem with an Emerald ECU a couple of years back and like you I was getting spark and fuel but it would cough and bang but wouldn't run. Eventually i swapped the pins round on the coil pack and everything ran like a dream. The ECU had been wired up round the wrong way. Worth a try?

Schrodinger wrote:I had a similar problem with an Emerald ECU a couple of years back and like you I was getting spark and fuel but it would cough and bang but wouldn't run. Eventually i swapped the pins round on the coil pack and everything ran like a dream. The ECU had been wired up round the wrong way. Worth a try?

Good idea but it doesn't pop and bang in fact it doesn't do anything at all I assumed the plugs would be wet as it wont fire but can hardley see damp

Rob, have you checked with the software to see if you get a cranksignal? Because a ECU won't do a bloody thing without getting a crancksignal

if its got fuel and spark you would have thought it must have a crank signal otherwise it wouldnt spark.? i hate electronics too

Werner Van Loock wrote:Rob, have you checked with the software to see if you get a cranksignal? Because a ECU won't do a bloody thing without getting a crancksignal

Yes , I did go through the pages on the laptop and once spun up , it recognised the sensor and showed 190rpm starting rev's. I'll go through it again but am so busy at the moment . Matt D. suggested that I isolate the ECU battery wise and give it it's own supply then see what happens

if you get fuel out of the injectors and get a spark from the plugs, then only timing can be wrong, ie plug firing order wrong

have you tested the spark with the software or by cranking with the plug out?
same question for the injectors.

because with cranking you can check wether you get a spark when the piston is up or down, should be up

Rob,
I'd second the advice from Matt. Had the same problem and ended running the ECU battery feed and the earth directly to the battery terminals.
Mike

mikeb wrote:Rob,
I'd second the advice from Matt. Had the same problem and ended running the ECU battery feed and the earth directly to the battery terminals.
Mike

Yes , me too . Think what Matt was saying was have a seperate ' battery ' just for the purposes of experiment . The very stupid thing is ---------- nothing's changed since it last started and ran perfectly apart from getting a brand new ECU from Dunnell. Since I fitted the engine it's run on Dunnell's spare ECU while waiting for his new batch of ECU's on order from his manufacturer .

Werner Van Loock wrote:if you get fuel out of the injectors and get a spark from the plugs, then only timing can be wrong, ie plug firing order wrong

have you tested the spark with the software or by cranking with the plug out?
same question for the injectors.

because with cranking you can check wether you get a spark when the piston is up or down, should be up

Yes , I'll try cranking with plugs out ---- I tested them via the laptop pulse tester .

Well it's turned out not to be the ecu in a manner of speaking. With the software adjusted NOT to shut down the ecu when insufficient voltage is delivered ---------- it started immediately Obviously I was not the person adjusting it being an electronics ignoramous Paul Dunnell says that his ecu requires maximum volts to function properly. I had it wired to battery positive via ignition switch and masterswitch. The choice was to disengage the volts sensitivity cut OR wire the ecu direct to the outgoing positive on the master switch with it's own dashboard toggle switch between ecu and master switch. I chose the latter . So now the ignition switch doesn't supply the ecu . All the little terminals on the ignition and master switches were dropping the volts from 14 at the battery down to 11 . Then with my 1.4kw geared starter the volts were insufficient , even though the starter wizzed the engine round .
His ecu and racing loom(microscpic wire diameter)being sensitive & the 3 volts leakage was enough to mess it about
At a later date I need to rewire the starting switch TO a proper RACE BOARD switch plus seperate starter -------- more work & pennies