r32 engine difficult to start

[quicky1980 0]

Hi all.

 

I've posted up on the r32 forum, but not positive results. Anyone on here able to give some input?

 

"Hi

 

I have a converted corrado which now runs a mk5 style R32 engine.

 

Each morning the car starts first time no problem so Im able to get to work (8mile journey on dual carriage way), but when I return to the carpark after work I sometimes have trouble starting. It's been getting worse and I dont recall having any issues over winter.

 

Today was so bad that after several engine cranks, probably a dozen or so it didnt fire and ended up running the battery flat. Had to get a jump start using a friends car which made mine start on second crank. My battery initially seemed fine.

Drove to the post office, go back to the car and again wouldnt start. 4th attempt it attempted to start (heard a knock) and died. 5th attemp started fine (backfired though, most likely due to the fuel in the chambers)

Then though maybe the fuel may be causing the issue as I ran a full tank of tesco momentum so filled up at the station with tesco 98ron, again it wouldnt start, several times it sounded to start ie slight fire but didnt burst into life finally it ran so got myself home and checked under the bonnet.

 

Nothing seems wrong under the bonnet, but I did notice that the top coolant hose was pressurised quite allot, more than I have ever noticed before. Coolant level looks ok with no oil. Oil looks ok with no mayo, checked under the oil cap while running and there was pressure, not sure if this is normal, and the engine ran rough until i refitted the cap.

 

Is there anything that could be a likely culprit, I wont be able to get it scanned for faults for a while and I need the car daily to get to work and back."

 

Fuel pump seems to prime ok, well I can hear it running anyway.

[mimjed 0]

cant claim to be an expert on r32's by any means. so it only does it at night? or randomly?

 

seems the issue is with spark, so id prob be looking at the coil packs/plugs/leads as a starting place.

 

engine management light flashing up at all?

 

as always though with a modern car, plug it in. saves faffing around.

[quicky1980 0]

Ill change the coil packs over just incase they are on their way out. Its wierd I know. But also very annoying

[chazrad 0]

Give someone like Tim at The Phirm or Vince at Stealth a ring. I'd trust Tim to give you some pointers, matey...(contact details for both on the web)

[Supercharged 2]

ECU relay or ignition switch??

 

Could be something stuck on maybe draining the battery - how about disconnecting when you get to work and then seeing what happens later...

[junkie 0]

I was going to say ecu relay too as mine did exactly the same and eventually never started again but I'm not sure how yours is been run with the management and modded wiring etc.

 

Get it changed immediately as if it is that it will die imminently. For me it was 2 in the morning and called the AA out which I said just send a low loader for me I don't want you to try and fix it. Then a "fixer" turned up and said I can't fix it and I can't tow you, I shall get somebody else out. Yea I told them that already. Then another turns up oh I can't tow you either. Then get the call saying we can't recover you. Thanks. So I'm stranded and it's now 6am. Walk home then shall I and sort it out myself. Wasters.

[Kevin Bacon 5]

If you hear the fuel pump prime, it won't be the ECU relay, nor obviously the fuel pump relay.

 

R32's always start immediately. If they don't, get it on VAG-COM. The ME7 ECU tells you everything you need to know.

[quicky1980 0]

I didn't think it would be the fuel pump relay would cause the issue as the fuel pump primes, however does it switch when key is turned to start and switch back when key is left in the run position?

 

Why wouldnt it be the ECU relay?

 

I need to find someone with VAG com near me, lets hope that Mark from SWICT allowed for connection via the plug.

[Kevin Bacon 5]

Because in a normal setup, the signal for the fuel pump comes from the ECU. If the ECU isn't working because the ECU relay is dead, how would the fuel pump relay get a signal? I know MK4s on have a door opening pump prime aswell, but the idea of the ECU and pump relays talking to eachother is for safety. If the ECU loses a crank signal, the fuel pump shuts off to prevent fires. As yours is a conversion, god knows how the ME7 box and Corrado relay board co-exist.

[fla 9]

if you haven't got the new relay, perhaps just bridge the two contacts to simulate a closed circuit and try it. Make sure its the relay contact connectors not the power + & - though!

[quicky1980 0]

hmmm, makes sense but not sure how it's been wired. I did wonder if the crank or cam sensors are playing up, until I get vag com'd I wont know, damn!

[fla 9]

not too difficult - look at the relay cover it'll have a wiring diagram illustrating power and operation sides. Just check the op sides and use a piece of wire or a twin spade connector if you have one made up.

[quicky1980 0]

right, Im returning from my business trip tomorrow but wish to order the fuel pump and ecu relays new from TPS. Tried asking for relays 167 (fuel pump) and 109 (ecu) but they said that they cant find these on the new system

 

Can anyone give me the full VW part number for these so I can get them in ready for my return? These may not be the root cause of the issue but it's worth a try, worst case Id end up replacing old tired weak parts with brand new items so would be a worth while activity.

[quicky1980 0]

just got back form Germany and found that the relays are 167 and 80 (thought this should be 109??), PN's are 357906381A and 191906383 respectively.

 

Both seem to klick so I now think they arent at fault. can they still click but still cause issues? Ill bridge the connections tomorrow once Im over the the travel tiredness.

 

Anyone in/near Peterborugh able to do VAG COM? My car is now not starting. :-(

Edited March 25, 2011 by quicky1980

[fla 9]

to check the relays, apply 12V to them directly - they should close and remain closed as long as power is applied to them. There should be no buzzing from them. I mention this because when i first checked my relays i pulsed them and they 'seemed' ok - time consuming mistake it took me 1 year to come full circle and find that just the ecu relay was faulty :( Are you getting fuel or spark or neither? Just sounds like something basic (hopefully)....

[quicky1980 0]

tbh I did a quick check so cant say for certain if i have spark or fuel to engine. will be going through these things this weekend.

 

if the relays are intermittently faulty, wouldnt this mean the engine would stop as your driving. not just when cranking?

[fla 9]

could do, but will also affect cranking if the circuit is open when you are turning it over. I'm a bit far off otherwise i could brought my laptop over - i'm sure there's someone not too far from you though.

[quicky1980 0]

thanks, will give updates as I go.

[junkie 0]

Mine did die mid driving sesh as you mention.

[quicky1980 0]

well, I check fuses, relays and all seem ok. I even bridged the relay terminals and still no joy and ended up without battery power to continue, so got the charger out and tried cranking with everything as normal and it started!

 

I still dont think its the battery being flat but just incase Im going to get a new one from TPS and will hope that sorts it. The reason I dont think its the battery is that the car cranks quickly without struggle but just wont fire

 

Changed all coilpacks just incase they were causing issues.

[Jim 2]

I'm not very good with electronics, ampages and voltages but.. is it not possible that the battery could make the effort to turn the car over several times but simply not be putting out enough power to actually start the car?

[quicky1980 0]

possibly, but not sure. Anyone else know?

[Reggit 0]

It's definitely possible for a battery on it's way out to be able to turn the engine but not start the car - seen it before.

 

have you checked the earth straps battery to chassis and engine to chassis are good and haven't gone high resistance. worth a check by using a jump lead to connect a metal part of the engine to the battery -ve terminal.

[quicky1980 0]

well its very unlikely the battery as I had plenty of charge and was connected to a van with jump leads and it wouldnt start. took about 20+cranks before it fired into life.

 

Im fearing the worst, the engine seems very hot and the top coolant hose is pressurised more than I ever remember seeing it. could it be head gasket related? Or am I just being over paranoid.

 

Still struggling to find someone with vag com!!

[mic_VR 3]

If you're really struggling to find someone with Vag-com you could try mrbeige. He's based near Ely.