Ignition fault or vacuum?
Ignition fault or vacuum?
Nothing else to do so went for a spin bearing in mind the car has been running great!
I join the motorway and accelerate to 70mph no issues drive for about 15 mile and decide to come off the motorway and head back. Drive down the exit ramp to the roundabout and the traffic lights are on red the car comes to a halt and the engine starts to bog down so much it stalls. The car is Auto. It fires up on the button and runs sweet I then select drive to move off and it bogs down again so much it is rocking the car so I flick it into neutral until ready to move off.sets off up the access road back onto the motorway sweet as a nut and accelerates to 70mph no issues. Come off the motorway again and same thing bogging down until accelerating any ideas?
I join the motorway and accelerate to 70mph no issues drive for about 15 mile and decide to come off the motorway and head back. Drive down the exit ramp to the roundabout and the traffic lights are on red the car comes to a halt and the engine starts to bog down so much it stalls. The car is Auto. It fires up on the button and runs sweet I then select drive to move off and it bogs down again so much it is rocking the car so I flick it into neutral until ready to move off.sets off up the access road back onto the motorway sweet as a nut and accelerates to 70mph no issues. Come off the motorway again and same thing bogging down until accelerating any ideas?
Type 411 Le four door auto .
- purplepeter
- Posts: 2339
- Joined: 8th August 2006 - 4:41pm
- Location: Bath, Avon
Re: Ignition fault or vacuum?
I can't be much help with FI
But have you thought of Fuel Filter?
Talk nicely to her
But have you thought of Fuel Filter?
Talk nicely to her
Re: Ignition fault or vacuum?
Agree with peter, check for a fuel issue first. Im not very expereinced on FI either.
The sultan of swing
- 937carrera
- Posts: 1190
- Joined: 7th June 2013 - 11:54pm
- Location: North Yorkshire
Re: Ignition fault or vacuum?
Bogging down because it is too weak or too rich when in D on idle. I'm thinking too rich, rather than lean ?
Being an auto makes things more difficult to diagnose too.
Does it bog down when cold and in D as well, or only when hot.
I'm thinking maybe the cold start injector is staying on, but that's just a guess. You could always pull the electrical connector off and see if that makes a difference
Being an auto makes things more difficult to diagnose too.
Does it bog down when cold and in D as well, or only when hot.
I'm thinking maybe the cold start injector is staying on, but that's just a guess. You could always pull the electrical connector off and see if that makes a difference
David
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon
Re: Ignition fault or vacuum?
Cheers guys for the input. It’s definitely running rich the plugs are jet black but it’s always run rich, the thermal switch is also disconnected. I’ve never had this issue before. The throttle valve is correctly adjusted as well. I wouldn’t know about cold injector, but no issue when first started all was smooth.
Type 411 Le four door auto .
- 937carrera
- Posts: 1190
- Joined: 7th June 2013 - 11:54pm
- Location: North Yorkshire
Re: Ignition fault or vacuum?
Which "thermal switch" is disconnected ?
Auxilliary air valve and thermo time switch are necessary for proper running
The 5th / cold start injector is located on the central manifold. If you remove the electrical connection it cannot inject (but if it is broken it might just dribble fuel in)
Have you downloaded and read the a D-Jet diagnostic manual ? It's worth spending an evening or two getting an understanding of how it all works
Auxilliary air valve and thermo time switch are necessary for proper running
The 5th / cold start injector is located on the central manifold. If you remove the electrical connection it cannot inject (but if it is broken it might just dribble fuel in)
Have you downloaded and read the a D-Jet diagnostic manual ? It's worth spending an evening or two getting an understanding of how it all works
David
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon
Re: Ignition fault or vacuum?
Hi David, that makes sense the switch is brand new but was not connected I asked the previous owner why that was he said for some reason it didn’t work properly he replaced the switch and still no joy. However he said it’s only employed for a couple of minutes so can be left disconnected.search me! I’m wondering if the air distribution box is faulty hence the rich running but that’s another matter, however it runs really well plenty of power. Yes I have a few manuals on the D tronic system all a bit over my head.
Type 411 Le four door auto .
Re: Ignition fault or vacuum?
Id be surprsed if the thermal switch is only working for a short period? Or is there more than one? The engine will need some means of knowing how warm it is in order to adjust the mixture accordingly.
The sultan of swing
Re: Ignition fault or vacuum?
Exactly what I thought! But he says it’s cold start only. Been having another play today and plug lead no 3 was not clicked on properly and refuses to. I’m ordering a new set from Just Kampers. Hopefully this will cure the problem.
Type 411 Le four door auto .
- 937carrera
- Posts: 1190
- Joined: 7th June 2013 - 11:54pm
- Location: North Yorkshire
Re: Ignition fault or vacuum?
I would get a better quality set from elsewhere.........
David
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon
- purplepeter
- Posts: 2339
- Joined: 8th August 2006 - 4:41pm
- Location: Bath, Avon
Re: Ignition fault or vacuum?
Speak to Mike Dempster
Re: Ignition fault or vacuum?
Cheers. I don’t know of Mike Dempster, does he have a company or a member on the site?
Type 411 Le four door auto .
- purplepeter
- Posts: 2339
- Joined: 8th August 2006 - 4:41pm
- Location: Bath, Avon
Re: Ignition fault or vacuum?
Miketyp3 on here
Re: Ignition fault or vacuum?
Just tried to send Mike a message, doesn’t seem to seem to be successful. I clicked on message icon wrote message and added Mike as recipient pressed submit. Doesn’t appear to have sent. Is this the correct way?
Type 411 Le four door auto .
- 937carrera
- Posts: 1190
- Joined: 7th June 2013 - 11:54pm
- Location: North Yorkshire
Re: Ignition fault or vacuum?
It goes into the outbox.
When read it moves to the sent messages
You have an unread message from me
When read it moves to the sent messages
You have an unread message from me
David
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon
Re: Ignition fault or vacuum?
Yes read your message, wish I was more techie it’s a struggle being thick.
Type 411 Le four door auto .
- 937carrera
- Posts: 1190
- Joined: 7th June 2013 - 11:54pm
- Location: North Yorkshire
Re: Ignition fault or vacuum?
Nah, you've got it now, the question on sent messages comes up frequently for new users
David
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon
- packers1712
- Posts: 196
- Joined: 7th October 2010 - 8:58am
- Location: Bedfordshire (nr Luton)
Re: Ignition fault or vacuum?
Rob,
Regards the temp sensors/thermal time switches, I'm not too familiar with Type 4 set up but the Type 3 uses 2, one for measuring temp at the cylinder head above no 4, if it is disconnected the engine wont run its kind of a failsafe as long as it has an out put that is too hot the engine will run, the other is more of a traditional sensor that tells the ECU to inject for longer when it reads cold and progressively shortens injection duration as the engine warms up, if this one is disconnected the ECU defaults to a long injector open duration equalling a rich mixture.
Doug.
Regards the temp sensors/thermal time switches, I'm not too familiar with Type 4 set up but the Type 3 uses 2, one for measuring temp at the cylinder head above no 4, if it is disconnected the engine wont run its kind of a failsafe as long as it has an out put that is too hot the engine will run, the other is more of a traditional sensor that tells the ECU to inject for longer when it reads cold and progressively shortens injection duration as the engine warms up, if this one is disconnected the ECU defaults to a long injector open duration equalling a rich mixture.
Doug.
Re: Ignition fault or vacuum?
Yes I get that, however if I connect the thermal switch in the centre of the intake manifold it hunts, disconnect no hunting. I’ve no idea.
Type 411 Le four door auto .
- packers1712
- Posts: 196
- Joined: 7th October 2010 - 8:58am
- Location: Bedfordshire (nr Luton)
Re: Ignition fault or vacuum?
Unfortunately looks like you are going to have to do some in depth component tests to try and diagnose the cause of the hunting!
- 937carrera
- Posts: 1190
- Joined: 7th June 2013 - 11:54pm
- Location: North Yorkshire
Re: Ignition fault or vacuum?
I agree
Hunting generally used to be put down to the auxiliary air valve IIRC.
From what we know the system does not have all the components connected, and as each of them performs a function it isn't going to run properly until each of them is sorted. Then it will all be sweet
Starting point I suggest would be ensure each component is actually wired correctly against the wiring diagrams. Assume nothing as it seems like a previous owner may have been messing.
Hunting generally used to be put down to the auxiliary air valve IIRC.
From what we know the system does not have all the components connected, and as each of them performs a function it isn't going to run properly until each of them is sorted. Then it will all be sweet
Starting point I suggest would be ensure each component is actually wired correctly against the wiring diagrams. Assume nothing as it seems like a previous owner may have been messing.
David
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon
1974 412LS Variant
1973 412LE 4 door Fastback / Saloon
Re: Ignition fault or vacuum?
Yes I agree I need to sort a few things out. I don’t think it’s that far off, overall it runs very well just a couple of issues occasionally.
I need to sort the stalling issue first then I think move onto the hunting, I’m feeling optimistic well let’s face it I’ve got plenty of time to get it sorted! Thanks for the input guys.
I need to sort the stalling issue first then I think move onto the hunting, I’m feeling optimistic well let’s face it I’ve got plenty of time to get it sorted! Thanks for the input guys.
Type 411 Le four door auto .
- packers1712
- Posts: 196
- Joined: 7th October 2010 - 8:58am
- Location: Bedfordshire (nr Luton)
Re: Ignition fault or vacuum?
You're welcome good luck and let us know how you get on as its all good info for help trying to diagnose problems for others in the future!
Doug.
Doug.
Re: Ignition fault or vacuum?
Update, my new plug leads turned up, and yes the quality is not good in comparison to the originals. So I just replaced the faulty plug cover with a new one, locked in ok. Fired the motor up all seemed well no missing, went for a quick spin down the motorway to the (supermarket) it ran smooth with plenty of power. Then disaster came off motorway to set of lights same problem missing and stalling. Some of the guys think fueling is the problem, would that more than likely be a sticking injector?
Type 411 Le four door auto .