Hi there, new to the forum, recently installed a Vems setup into my Rover V8 Capri, with the help of dnb and Tony C.
Quick summary:
3.5 Rover v8
3.9 Hotwire injection system (all stock parts)
Mallory distributor
Vems IAT Sensor
ECU is only controlling the fuel at the moment.
Story so far
First off tried fiddling with the settings for a few nights, engine shows signs of life but wont actually start. Had problems with rpm spikes when cranking (would go up to 25500rpm) so dont think that was helping.
Then a dodgy IACV/stepper motor fried the stepper control chip, which dnb replaced and I got the ECU back today.
So starting from scratch again, first thing is that the ECU no longer seems to trigger the fuel pump (possibly another dead chip?) so have wired pump in manually for now, i turned on trigger filtering which seems to have cleared up the rpm spikes too. Engine is same as before, fires/cranks/fires/cranks but wont actually start.
This is the current MSQ file.
http://www.box.net/shared/3lyy9648w8
I will upload a datalog tomorrow evening.
cheers
Stuball
None of the other Rover guys had settings that "just work" for you to try? I haven't looked at your config yet as I'm at work, sorry. Rob might beat me to it.
Right then, after realising that i had wired the fuel pump up wrong so that it didnt run when cranking, the engine now starts, and then stops lol.
The settings at the moment are roughly based on Tonys (thev8kid) and its pretty close to running. This is the MSQ file after finishing up for tonight.
http://www.box.net/shared/3lyy9648w8
And the datalog for this evening, as far as i can tell the engine has a BIG airleak, when it does run the revs are up down up down and then it stalls. A few blips of the throttle get the revs up and smooth temporarily but then it dies so got to sort the leak before i try again.
http://www.box.net/shared/v5lwk04oo8
cheers
Stuball
Small update.
I have resealed my trumpet base and plenum, and now the engine doesnt fire at all, not even 1 cylinder ???
Im baffled, checked i hadnt forgot to plug something back in so its not that.
Any suggestions?
Stuball
Do you have stable RPM? Is there voltage at the injectors?
What PW does MegaTune display on the main screen.
hi rob,
Yeah rpm is stable, around 100-200.
PW is about 8 when cranking.
Definetely voltage at the injectors, everytime i try and start it, if i pop the plugs out they are soaked. Ive checked for spark and its good on all cylinders.
Stu
wet plugs?
Now you've got rid of the air-leaks I'm betting that you're well rich with cranking, and thats flooding the engine.
Are you on alternate or batch firing for cranking? (Settings->Injector Settings)
What is your req_fuel value?
Rob
Firing is set to Alternate
Req_fuel is 11.0 at the moment
After lots and lots of cranking it sputtered a couple of times today but that was it.
Stu
Alternate is good, what about your cranking PWs? (Settings->Priming cranking afterstart)
You may have noticed that if your throttle position is more than 50% PW goes to zero, this is the flood clear feature.
So if you make sure that the petrol has evaporated and that the plugs are clean, you can start cranking with your foot on the throttle, and allow a little fuel into the mix by closing the throttle briefly, the engine should catch much quicker and allow you tp start to tune the cranking PWs easier.
Rob
Last time i tried cranking PW was set to 10.0
Will have to try the half throttle feature tomorrow (removed plugs and letting evaporate overnight, plus battery is a bit dead lol)
Theres cold cranking and warm cranking:
(http://www.vems.co.uk/VEMSUserManual/PrimingCrankingAfterstart.png)
Oops lol.
Cold cranking is 10.0
Warm cranking is 2.0 (although its not got Warm yet lol)
Coolant was about 10 degrees.
That might even be a little too lean...
Normally I guess PW cold of 2 to 3 x Req fuel (22 to 33 although the max is 25.5) and 0.75 x Req for warm (8.25)
Right, with a fresh battery and about 20 seconds of cranking the car finally came to life.
Now the issues.
1. The car runs for about 5-10 seconds then stalls
2. The rpm reading is all over the shop, either its a bad signal or just becuase the engine is really rough im not sure. This intern sends the PW bananas lol
3. Tried to get the revs up with the throttle but as soon as i touched it it nearly stalled the engine
4. I checked my IACV on Tonys advice as its supposed to move in an out when the ignition is turned on. It didnt move at all.
This is the msq file and datalog.
MSQ
http://www.box.net/shared/ax1d9pickw
Datalog
http://www.box.net/shared/0lqrwi1s0c
cheers
Stuball
have you tried catching it on the throttle stu to try and keep it running?
looks liek you need to set the stepper motor up, oh joy of joys o have been here, get ready for some hair pulling mate ;
i did have the stepper settings written down that Dnb gave me i think it started at abcd and so on and gave the hex values etc and what to put into MT,
but have lost it :(
my IAC step Sequence is set at 99
try that mate,
Big trigger problems there - I am suprised we're not seeing the Trigger Errors panel flashing on MegaTune.
When i managed to get the revs up last firday, albeit temporarily, the rpm smoothed out, is it not just the really rough running causing the errors?
will get the stepper motor working before i try again now.
Stuball
Stepper motor wont cure that problem, invest your efforts investigating the trigger issues.
Just a quick check here.
As i Have the standard Distributor/Coil setup, what pin should the wire from the negative side of the coil go to?
Stuball
EC36-pin27 is the primary trigger
(http://www.vems.co.uk/VEMSUserManual/ECConnectorsOut.png)
There's a text file hidden away in the firmware folder in the Megatune distribution. This gives all the combinations of stepper values (in hex) to try.
I agree with Rob that cold cranking is a bit lean. Also check that when the afterstart period ends (usually a couple of seconds), the VE table is sensible.
OK small update here.
rob is looking at my ecu at the moment as it wasnt triggering the fuel pump on any of the p259 channels.
in the mean time I got hold of a stock rover injection system and fitted it as i needed the car running.
Had exactly the same problem, the car would run for a few seconds then stop, or not run at all, and kept flooding.
however, today I solved the problem, it turns out I had the wrong spark plugs (too short), fitted which is why she wouldnt fire. Put some new ones in and it runs really well on the stock system.
fingers crossed when i get my VEMs back and plug it all in it will also work.
Watch this space.
Stuball
Got a replacement ECU from Rob yesterday (cheers for that!)
Plugged it all in and she fired up straight away.
Now i just need to know where to start, cold idle is a tad fast @ 1800rpm and when hot the idle goes up and down in regular intervals.
FYI Rob this is with the stepper motor plugged in :)
Here is the datalog and current Msq file:
http://www.box.net/shared/ogjl4pmw40 Datalog
http://www.box.net/shared/rs7osms8c8 MSQ
Second datalog of a quick drive round the block:
http://www.box.net/shared/bawpu5gysk
Just to add, did a quick test and the hot idle is quite steady (albeit a bit high at the moment), until the lambda starts reading. The EGO correction seems to be making the idle go up and down
glad to see it was not a wiring issue mate ;-)
Nope, it was a very rare LBUS failure, I couldnt figure out what was wrong after replacing the components again and then I wondered why the wires for the analog in were hot... Measured 5v that didnt seem to be an issue - put the scope on it and it was strobing like a mad thing.
So Stuart got a replacement under waranty.
You have to remember that from my obscured viewpoint the general rules are:
no fuel pump = blown p259 = bad grounding.
No stepper = blown stepper chip = 12v fed to stepper chip (often by shorted stepper wiring).
I'd never heard of an LBUS failure 'till I told VEMS about the measurements!
i was starting to get worried as i made the loom for him :D
when every one kept on about bad grounding etc,
Stu.
have played with your ve table mate, tell me when your ready i'll send the .msq back, run her up and do me a datalog again plz mate.
Rob.
one thing which has got me confussed,
mine and stus.s are wired the same, but why do we have different injector outputs??
What should the MAP be reading at cruise?
Mines sitting at 30kpa. But my VE Table starts at 30.
Should my table start lower than this?
MAP at cruise depends on the cam and a whole load of other smaller factors. (I presume your cam is pretty tame ;) My MAP on cruise is 45kPa )
30kPa is OK but a little low - best double check the sensor calibration since this is a new unit. I'd consider rescaling the table to start at 10 or 20 if the calibration is currently correct.
Injector outputs are probably not all that different since they are both batch fire in groups of 4. There are 2 ways of doing this - as left and right hand banks, or having every second cylinder (in firing order) in each batch. It doesn't matter much which way is used, but I have a slight preference for the latter.
Here's what I think the next VE map should be. It's not too bad as it is, but it does run quite rich in places and lean in others.
600 900 1200 1700 2200 2700 3200 3700 4200 4900 5800 6800
30 26 25 20 21 20 22 28 34 40 47 56 60
40 25 25 21 25 26 27 35 39 46 55 63 66
45 23 24 27 26 32 30 39 43 50 58 66 69
55 25 27 31 36 42 38 50 56 61 68 72 73
60 27 31 35 40 45 53 50 55 70 75 77 76
65 30 35 43 46 54 62 59 64 80 83 82 81
70 35 41 47 56 62 62 68 69 89 91 88 84
75 46 52 58 67 67 75 74 76 98 98 94 88
80 57 63 67 75 76 83 83 82 106 106 102 93
85 64 71 76 84 90 94 87 89 114 115 108 99
94 72 80 86 94 99 106 108 121 125 126 118 108
104 77 86 91 100 83 89 127 133 136 136 130 118
I hope it formats OK - row and column headings are MAP and RPM bins from the msq.
The MAP sensor was calibrated using the local weather station's pressure readings.
TonyC: Only dnb knows why the injectors are ordered like that - for as long as they're batch fired order doesnt really matter much.
ok no worries,
was just curious that was all, as tried stus injector outputs on my vems and mine refused to run.
I did answer the injector question in my last post - but I have no idea why your car should decide to not run with those settings!!
Well car is all up and running now.
Tony has helped a lot getting it roughly setup etc. Did a 200 mile round trip today and it seemed quite happy.
We are having one problem though
We re-did the ve table to start at 5kpa instead of 30. We burnt this to the ECU. The problem is that if i then open up megatune and turn on the ECU, the ve table still starts at 30kpa?? It doesnt seem to save the new table..
STU
Disregard the above, sorted it now