GTV6 Dreaded Start then Stall

[shane wescott]

Hi Guys
Now that I have a repaired Dual relay (see other post) I ASSUMED the GTV6 would fire up and all would be forgiven.

I was dreaming.

So during my research to repair the relay I found a web page a guy called Greg  http://www.hiperformancestore.com/Ljetronic.htm

Which tells all about the GTV6 fuel injection system - good thing too as I needed it.

So here is what happens now.

I have fuel, I have fuel pump, I know this because I can hear it start.

Turn the starter and the starter kicks in and the engine fires briefly. If you start again you will get a second kick.

Any touch of the accelerator and it stops dead and you have to wait  a minute or so before a second attempt, and it kicks again and then stops.

So reading through all the info Greg referes a couple of times to the "Dreaded Starts then stalls" issue.

Congratulations Shane, this is what you have.

So it sounds to me like the cold start injector is working, and there is obviously some sort of timer (maybe part of the ecu ) which will only let this fire once and then it assumes the engine will kick in.

Things I have tried.

Checked hoses, I have relatively new silicon ones so they feel and look o.k. I did find the consatina hose to the Air Flow Meter wasnt on properly so put that one correctly - all excited - no luck.

Checked earths, found the earth from the plenum to the engine was broken, so repaired that - all excited - no luck.

I found that MOST of my fuel connectors to the injectors were loose and one of them was leaking !!! - tightened them up - all excited - no luck.

By this stage I was getting pretty pissed off and the Ducati was having a chuckle in the corner so I threw a cleaning rag at it and now I need to clean the tank again :-(

I read the bit about the AAV and realised I had never cleaned it so off it came, cleaned it out, chucked it in the freezer, it sort of opened but not fully so maybe an issue - comments from anyone ??

I also noticed that a couple of the fingers inside the connector for the throttle sensor were missing so maybe the top wire is not connecting properly - likely to be the cause anyone ??

For some reason it will not fire more that using the cold start injector. I checked the other part of the relay I fixed and volts are getting sent to the Injectors.

So I am at a loss at the moment, any ideas would be welcome.

Thanks in advance.

[dehne]

how are the injectors maybe a couple are blocked/knacked this can cause a car to stall have had it happen before in a engine transplate for one of my old 90's engine ran great before the did not work after put clean injector in and all was good again, maybe something to look at if not done already

[shane wescott]

Cool Mate.

Have never had them out, they could be blocked. I've seen where the guy talks about testing the cold start one so I imagine it would be the same. Not sure if you can just pull them out and clean them and put them back ??

Ta

[shane wescott]

Good tip MAte.

Will do.

[Al Campbell]

Shane,

The cold start injector is controlled by the "Thermo time switch" which is mounted on the thermostat housing on the driver's side. It is supposed to disable the cold start injector when the temperature reaches 30 to 40 C. See Greg Gordon's tuning guide for how to test the sucker.

Throttle switch sounds a worry. Should be three contacts on that. If you carefully move the throttle by hand you'll hear a faint click. That's a switch telling the ECU that you aren't at idle anymore. The ECU then works out injector duration based on all the sensors. If you keep moving the throttle, a bit after half way you'll hear a second click, which is the flat out setting. Greg Gordon's tuning  guide explains it all in more detail.

If contacts are missing off the connector then it could be the middle stage  and when you first touch the accelerator the ECU knows you're not idling but isn't getting the right signals and does the wrong thing. Those connectors are pretty robust so maybe one of the contacts is just bent.

Good Luck,
AL.

[shane wescott]

I will check out these clicks tonight Mate.

I did read something last night which sort of said if you pull this connector off the car should idle. I think it was a BMW preso on the bosch FI which is the same as the GTV6 one.

Anyway I will let you know and at a pinch I might even gerryrig the wiring to bypass my potentially dodgy connection.

catch ya

Shane

[Al Campbell]

I actually drove my car for about an half an hour with the throttle connector unplugged, after working on the car the day before. The most noticeable effect was when backing right off after acceleration the motor would stumble, almost stalling before quickly recovering. It must have been mostly using the AFM. Popped the bonnet to find the connector flapping around.

AL.

[aggie57]

Shane,

Are you sure that there is 12 volts getting to the double relay?  It comes directly off the back of the fuse box and not having that connected will show exactly the symptoms you describe.

Alister

[shane wescott]

I am pretty sure.

After spending a couple of hours mucking around with a rebuilding the relay over the weekend I measured the 12 volt input to the injector relay points, and also the output and there was 12 volts there.

I will recheck tonight and I will make sure I can hear the second relay click and see the volts.

I might also see if I can get volts on the injectors. The cold start one obviously has volts but this comes from the new relay I instaled, not the second one.

Thanks for the prompter.

Catch ya

Shane

[wombat]

I am not sure if you have covered this as I haven't read all the advice but I had an issue with my GTV6 which turned out to be the inertia switch. I bipassed it and it ran with no problems.

[dehne]

just a quiock thought shane does the car run with the cold start plug not cliped on mine stuffed up and sort of had the same probs cant remember as its been 3 years or so but i just pulled clip of and have not ran cold start since then maybe same prob for you

[shane wescott]

Thanks for all of the advice so far Guys.

Bit side tracked tonight but went out just then to discover the Alfa Fairy has not fixed my car - bugger - maybe if i leave an espresso on the bonnet tonight I may get lucky :-)




So firstly, normal start, still the same starts runs for a few seconds and dies. Does this about three times in a row, must be because it is colder tonight - yesterday it would only do it twice in a row.


So firstly disconnected the power connector from the cold start injector - now it didnt kick at all so this proves that the only reason it's starting at all is due to the cold start injector :-)

Put that back on and now disconnected the throttle sensor connector, just incase a broken wire means dodgy stuff goes back to the ECU and causes the prob - no luck same symptoms, starts then dies.

Hopefully tomorrow night I will get a bit more time and will do the inertia switch bypass (any ideas where it lives), and pull out the AAV again and set this for full open.

Catch ya

Shane

[shane wescott]

OK Guys

Getting excited now.

When I pulled the Dual relay off, it came off a number of times. I tried to keep the wiring in it's little groups so I didnt mix things up.

Now, when I was doing a check on the second relay, just to be sure to be sure, i noticed that the colour codes seemed out of whack with the wiring diagram that I have.

In fact it looks like some of the wires are on the wrong connectors and this would certainly cause my issue.

Now I am trying to be cautious, if I did stuff up which wire is on which connector I am cool with that but I dont want to misswire anything and blow the ecu for example.

So I will probably just meter out the wires and make sure the diag and the markings on the outside of the relay are correct, put the wiring as per the diagram I have and "hopefully" this wil make it run.

Catch ya

Shane

[aggie57]

Sounds like you're on the right trail Shane.   

[shane wescott]

Quick Update.

Did some rewiring and I am now able to get consistent crap running for a longer period of time. Thought I had positioned the relay wires so I couldn't stuff it up but looks like I have.

The benefit of this is I will meter out and create a map of the wiring and also what each one does and how the dual relay works so hopefully this will help someone in the future.

I will post the info when I finish. In the meantime if someone with a 84 - 86 GTV6 would possibly post a photo of the underside of the dual realy that may help. I could see how someone elses is wired.

Catch ya

Shane