What's new
There is more to life with TurboRenault.co.uk

Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

  • This section contains the archived boards. They should be read only. If you want a thread resurrecting please message admin and we can move into the live section

newbie with an overfueling mk1

S

Sam&Lewis

New Member
hi guys.

sorry this is my 1st post. i will do an intro thread with my new car pics etc.

but unfortunately after 1 day of ownership my mars red supercharged v6 it has broken down.

car was fine on test drive and drove perfectly home on the 290mile journey last friday. however on saturday while out driving it started being really sluggish
and all of sudden stalled and wouldnt start up. then after 20 minutes got it started again but it wouldnt rev past 3000rpm.

now it will start but will not rev past 2000rpm and really struggles to actually rev up to 2000rpm

when i put my foot on the throttle it struggles to rev and sometimes just dies

seems to be overfueling badly and there is really bad petrol fumes coming out of the exhaust.

with it having a super charger obviously its running a piggy back ecu. an omex 710 series. with this it has constant engine management light on. i have had the standard ecu dianosed and have ignition, injector and coil faults. speaking to the guy who done the coversion and he says these are expected as the standard ecu doesnt control these and the omex maps do.

i have changed the map sensor as its running an escort cossie sensor but no difference. still the same symptoms

i understand with it being a supercharged vee that may have something to do with it but if anyone has had any of the above highlighted symptoms please let me know. or if anyone has any ideas then please again let me know.

my boyfriend is going to try and sort the car for me but if no luck then its back up to the bloke who built the car 300 miles away!!!!!

thanks sam
 
Welcome..
It's possible one or more ignition coils has failed, which is not uncommon with the V6.........car usually sounds rougher when this happens as well.
There's plenty of info on here about it and about changing coils.......Hopefully it's nothing more serious but don't do a 300 mile drive without finding out what is wrong first.....you may do some damage.

Tim
 
the car will not drive anywhere. its like its only running on 2 pots.

gonna go out now and take a look and try the process of ellimination
 
Tim is quite right about coils and checking them ...

I would also suggest checking to make sure you have the right grade of spark plugs and that a couple of em haven't melted.

Hopefully it will be a coil issue.

Martin
 
i checked the 3 2day which are easy to get to and when disconected they made the engine struggle even more. so these seem ok. am going to check the other 3 in the morning, am preying its them. its def not running on all cylinders and the unburnt fuel is just getting thrown out the exhaust cuse i was afraid to have a fag!

if i cant diagnose the fault then i gotta make a 600 mile round trip with the car on a low loader to the company who built the car.

i shall try and get a clip of sound to see if it sounds like a coil issue

cheers for the help
 
Be carefull with unattendet feeding fuel in the Cats, if they are still fitted. You risk torching the whole car.
Most obviously it will be a coil since you're missing at least one cylinder, but the fuel still comes out of the injectors.
 
the engine work was carried out by a company call gt40 supercars. they're top blokes and have been on the phone every day with ideas of the problem. but because its running the charger i dont have many options but to go back to them. they really know they're stuff but theyre the other end of the country and diagnosing fault over the phone isnt easy, but theyre determined. and maybe coming down to have a look!!!

the vee in question is the one that was on ebay a few months back for 16500 with minimal description and crap photos.

its running top of the range omex management. a vortech charger and not sure on boost although i know its very low as its not cooled but its running over 300bhp - flew on the way home :)

but i think its been mentioned before, it has a standard exhaust!!! which im in the process of trying to find a full system so if anyone knows of a good exhaust for sale let me know.

thumb.jpg

thumb1.jpg

thumb2.jpg
 
down in the south my friend.

ive had the coils and plugs out today.

3 of the coils on removal the tops seperated from the bottom!!

and all 6 plugs where sooo black and minging its unreal. 2 of the plugs where dry like they had been firing and 4 where wet with fuel as if they hadnt been firing.

i have 4 new coils and 6 new plugs. fingers crossed this evening it will be running.
 
If thats how it will carry on then thats gona be an expensive car to run, but then most non stanard cars can be a little unrealiable.

Wonder how long the gearbox will last pushing that power through?
 
I would suggest a compression test ... I know off too many people with experiences of forced induction and poor running not to do that as a matter of course. Plug fouling is a common symptom of melted pistons caused by detonation. I have also blown an engine myself being greedy with power resulting in these symptoms (not a Vee though BTW) - this resulted in me building a forged engine as you are suggesting perhaps.

When the car was for sale on e-bay I asked questions about the build of the car and whether it had forged pistons, what the compression ratio was etc. but don't seem to remember getting a reply. Does it have forgies in ? I wouldn't have thought a forged bottom end would be necessary nor connecting rods for that matter, but pistons would be recommended - especially if you have no intercooling or chargecooling to reduce the impact of the detonation your are likely to experience from time to time.

MikeT has experiences with a Pro-charger supercharger and also turbo chargers on a Vee.

Martin
 
the bloke who we bought it off didnt really know his cars he just liked the clio v6 and wanted more power. he said he spoke with various companies and choose the one who knew what they were talking about. a company called gt40supercars. phil there is helping me out now and should have the car with him next week.

the bloke who i bought it off had money in his pocket and paid 6500 for the conversion!!! which included uprated clutch and fully rebuilt gearbox, omex 710 series and brand new vortech charger, but stock internals and no cooling, which apparently wasnt an issue due to being run on low boost. which i can believe. however he wanted rid due to a baby so i done a part x on my missus 182 and the car was fine on inspection and drove home great.

gdi have done a compression test and got 200psi on the rear bank and 150psi across the front. they checked the timing and its apparently 2 teeth out?

i think its a sensor issue thats making it overfuel not det on pistons. or am i wrong?
 
I offer all the following in good faith represents are only my opinions and experiences ...

It's good to have done a compression test, always an essential thing with forced induction cars. A leak down test is also usually sensible to determine if compression rings are cracked - as this is quite common with stcok pistons and ring lands. You have made a good start. I am slightly concerned about the difference between the front and rear cylinder bank cylinder pressures, 10 % difference is normally an acceptable tolerance ... Are the fouling cylinders on the front bank ? I think you said 3 coils/plugs had fouled ?

Anyway if GDI think compression is OK (hmmm) that's a good start. Timing being 2 teeth out is a little worrying also, I can't imagine the belt has jumped though unless the engine has back-fired hard. The car ran fine to begin with so it has either slipped or is not contributing to your issues. Maybe it is just one bank/cam where the timing is out, may explain the lack of compression if the pistons are not in synch with the valves, this may then explain lack of ignition if the cylinder pressure is not sufficient to generate an adequate spark etc. I think the stock compression ratio is quite high at 11.4 to 1 which is high for a forced induction engine (normal is around 9 or lower) - so you are right to say the boost should be kept quite low ... Is there any chance the engine overboosted while you were doing your long drive ?

Next thing then is perhaps to ensure you have ignition on all cylinders/plugs etc. Traditional diagnosis of fuel and ignition systems basically which GDI should do to try and help point you in the right direction. If you have eliminated mechanical i.e. compression and timing (once that is resolved), then fuel and ignition next ... You could always disconnect your piggyback ECU and run the engine on the stock ECU at idle to see if it runs. Also you can drive the car (at your own risk) without boosting the supercharger to see if it runs. You will only run out of fuel map if you boost the supercharger so you should be able to elininate the piggy back ECU being faulty etc.

Also you mention sensors, these would typically be wiring issues so you can check all connectors for being fully seated or contamination from oil or water and make sure no wires/cables are chaffed or shorting if they are too tight or under tension. I assume the piggy back ECU uses the MAP sensor input to determine boost, ensure the boost control pipe is not kinked and preventing the boost signale from getting to the MAP sensor - depending on where it is located. Also ensure the map sensor electrical signal is reaching the ECU, this is the most essential input for operation under boost. A faulty map sensor can also impact idle on a turbo car as it throws fuelling out - and certainly did on my GT4 when I rebuilt the engine and forgot to re-connect the MAP sensor !! A map sensor measures negative boost aswell as positive and under idle and part throttle there is a lot of negative boost hence the impact if it is not working correctly - even when the engine is not boosting.

The crank position sensor is also important so check this too for signal. If the Wiki has the wiring diagram for the car there should also be sensor diagnostic checks that can be done i.e. with a multimeter etc. I would have thought if the stock sensors are retained - can you confirm, the piggy back ECU would not impact these and so the engine diagnostics on the stock ECU should be OK. Again my GT4 had a piggy-back HKS ECU and all OEM sensors were retained and all engine diagnostic functions and warnings were fully working. The piggy back ECU's typically intercept the sensor signals from the wiring loom and also fuel injector signals from the stock ECU with an additional boost signal and then create a new fuel injector signal based on an additional engine map. This is also why I suggest seeing if you can run the car on the stock ECU only to eliminate the piggy back ECU.

Anyway if any of this is any help or you want to speak to me feel free to PM me and I will be happy to help or discuss things. I am not a proffessional in the motor/tuning trade but am quite good at problem diagnosis on most things mechanical and eletrical - normally anyway LOL

Martin
 
You must log in or register to reply here.
Back
Top