Issue with wasted spark ignition

General Chat About Electrics, And Ignition Systems.

Moderator: phpBB2 - Administrators

minorv8
Knows His Stuff
Knows His Stuff
Posts: 571
Joined: Thu Nov 23, 2006 5:10 am

Issue with wasted spark ignition

Post by minorv8 »

My setup: Haltech E6X ECU, Bosch 407 wasted spark coils (same as P38), batch fire fuelling.

The problem: at steady speed like 55, 65 or 70 mph the engine occationally cuts for a second or so and then recovers. I had the laptop connected and there are no change of load site when this happens. So not anything weird in the maps. It is so sudden that I believe it is a problem on ignition side. Also, wideband shows rich mixture after this happens.

Now, what is really weird is that on full throttle it runs perfectly. I did 10 quarter mile runs today and it never missed a beat. Also, when it does cut you can go to full throttle and it revs clean.

I put new plugs in yesterday. Old ones were really good looking. Plug wires ard cheap P38 ones from Rimmers. I was suggested that it might be the plug wires. But it does not feel like dropping only a 1 cylinder.

Any ideas where to look for the problem ? crank position sensor, igniters, coils, ECU ?



unstable load
Top Dog
Top Dog
Posts: 1278
Joined: Mon May 04, 2009 6:53 am

Post by unstable load »

That is going to be difficult to find... If the engine is completely dying and not dropping a/a few cylinders, I'd think it's an ECU problem.

A quick Google with "Haltech E6X cutting out" reveals that you aren't alone....
Cheers,
John

minorv8
Knows His Stuff
Knows His Stuff
Posts: 571
Joined: Thu Nov 23, 2006 5:10 am

Post by minorv8 »

It does not die completely, but feels like it drops more than one cylinder, sort of resembles hitting a soft cut rev limiter.

DaveEFI
Gold Member
Gold Member
Posts: 4603
Joined: Fri Feb 26, 2010 4:27 pm
Location: SW London, UK

Post by DaveEFI »

Does this system allow you to log things?

If so, does RPM show a problem when this occurs? Or even the rev-counter?

With no tach signal to the injection, fuel and sparks are cut off immediately.

What sort of crank sensor are you using? Hall effect are more likely to go intermittent than VR.
Dave
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y

minorv8
Knows His Stuff
Knows His Stuff
Posts: 571
Joined: Thu Nov 23, 2006 5:10 am

Post by minorv8 »

Last time I tried to log the Haltech software refused to open its own data log :D :D so havent tried since. But rev counter does show a drop of rpm.

I have an intank 044 pump which is very noisy and it runs even when the engine cuts.

Crank sensors have been a nightmare, trigger wheel is a 36-1 for Rover from Triggerwheels. First sensor fitted was a generic Honeywell Hall sensor at could not read anything. Second one was a Opel Hall sensor that read rpm but could not see the missing tooth. Current one is Ford VR that seems to work.

Something to say about Haltech. Their manual lists Motronic wheels with setups but their tech support stated that the software never liked Motronic wheels... Go figure...

I guess I now have a good reason to buy a GoPro and try to get something on video.

DaveEFI
Gold Member
Gold Member
Posts: 4603
Joined: Fri Feb 26, 2010 4:27 pm
Location: SW London, UK

Post by DaveEFI »

If the software is designed to recognise a 36-1 then that should be OK. What is more likely is the tach input circuit isn't converting the signal from your CPS to nice clean pulses of the correct level that the processor can read reliably. A scope is the ideal tool for checking they are good. (It's also a very common problem with MegaSquirt installations, and likely others.

A hall sensor in theory should be best as this produces a constant level square wave - a VR gives a varying level sine wave which has to be converted to constant level square waves (pulses). But hall contain electronics, while a VR is just a simple coil. I've been using EDIS on my RV8 for years - and that used a VR sensor and 36-1. And was all bought used.

I'm not convinced any tach input is going to be truly universe and read any sensor ever made without some modification. So saying, Haltech should be able to recommend the best for their unit.

Cabling is important too. If the cable picks up stray pulses from the plug leads etc, you're in trouble.
Dave
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y

minorv8
Knows His Stuff
Knows His Stuff
Posts: 571
Joined: Thu Nov 23, 2006 5:10 am

Post by minorv8 »

E6X software has gain and filter adjustments for VR sensors.

But, if the signal is noisy/distorted or whatever, should it not get worse at higher revs ? Now the issue is at constant speed but it never cuts when accelerating.

Haltech loom has shielded wiring to crank sensor.

stevieturbo
Forum Contributor
Forum Contributor
Posts: 3979
Joined: Sat Nov 18, 2006 6:22 pm
Location: Northern Ireland

Post by stevieturbo »

Crank trigger etc is most likely place to be looking here....how repeatable is the problem ?

Can you make it do it, or is it just at random ?

The E6 really is an ancient old system, I think a lot of Haltech stuff of that century liked magnets on their trigger wheels ?

Does it record crank trigger errors at all ?

Has the setup ever worked well ? Or is this a new problem ?

Any HT leads routed near any crank trigger wiring ?
9.85 @ 144.75mph
202mph standing mile
http://www.youtube.com/watch?v=XgWRCDtiTQ0

DaveEFI
Gold Member
Gold Member
Posts: 4603
Joined: Fri Feb 26, 2010 4:27 pm
Location: SW London, UK

Post by DaveEFI »

minorv8 wrote:E6X software has gain and filter adjustments for VR sensors.

But, if the signal is noisy/distorted or whatever, should it not get worse at higher revs ? Now the issue is at constant speed but it never cuts when accelerating.

Haltech loom has shielded wiring to crank sensor.
Sounds the same sort of input as earlier MS. My view is if you need a filter, better to sort the noise at source.

Sadly, it's difficult to diagnose what could be any one (or more) of a number of things.

I'd try and get the logging working. That should show if is is a tach signal problem, or not. Or is there a real time error display for the tach signal?
Dave
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y

stevieturbo
Forum Contributor
Forum Contributor
Posts: 3979
Joined: Sat Nov 18, 2006 6:22 pm
Location: Northern Ireland

Post by stevieturbo »

9.85 @ 144.75mph
202mph standing mile
http://www.youtube.com/watch?v=XgWRCDtiTQ0

minorv8
Knows His Stuff
Knows His Stuff
Posts: 571
Joined: Thu Nov 23, 2006 5:10 am

Post by minorv8 »

It is random. Only way is to drive at constant speed and wait for it to happen. It would be lovely to get the logging working but it might require a fix in Haltech software. Which is not going to happen since it is obsolete. I even got a reply from Haltech that this ECU is an old product, get a newer one.

Yes, Haltech did recommend ditching the Motronic wheel and buy one with magnets.

I bought the ECU new roughly 10 years ago but only got to fitting it 2 years ago. Local legislation did not allow me to replace the carb with EFI. Apart from this random issue it works as it should. I bought a new crank sensor today and will try it. The next step will be better plug wires.

User avatar
Ian Anderson
Forum Contributor
Forum Contributor
Posts: 2396
Joined: Sun Nov 19, 2006 9:46 pm
Location: Edinburgh

Post by Ian Anderson »

Sounds like a problem a mate had been n his GT40
He has a speedo that counts the pulses of CV bolts passing the pick up sensor, similar to yours

Every so often his speedo would drop to zero. Then it would start again.

Turned out the sensors are quite temperature sensitive, and heat from the engine block, headers etc was enough to cause the sensor to "fail" intermittently.

He made a scoop from air under the chassis and directed it onto the sensor which solved the problem.

Ian
Owner of an "On the Road" GT40 Replica by DAX powered by 3.9Hotwre Efi, worked over by DJ Motors. EFi Working but still does some kangaroo at low revs (Damn the speed limits) In to paint shop 18/03/08.

DaveEFI
Gold Member
Gold Member
Posts: 4603
Joined: Fri Feb 26, 2010 4:27 pm
Location: SW London, UK

Post by DaveEFI »

An intermittent fault like this means something is occasionally faulty, then clears. :D
If it didn't work at all, perhaps magnets would be the answer.
It might well be heat related - but at speed airflow would normally keep things cooler than at other times.

Intermittent electric faults are usually connectors, or a dry solder joint in the electronics.

If the tach input circuit on the Haltech is known to be iffy, I'd be inclined to fit a newer one. Add on twin input VR boards can be easily bought for MS, and are self adjusting. But you'd need someone who knows Haltech to fit one.

Of course it could also be a software glitch.

Really, you need to find out what the cause is before you can fix it.

Is there a Haltech forum you could ask on? It's very rare to have a unique fault.
Dave
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y

minorv8
Knows His Stuff
Knows His Stuff
Posts: 571
Joined: Thu Nov 23, 2006 5:10 am

Post by minorv8 »

Yes there is a forum: http://forums.haltech.com/viewforum.php?f=11

But, very infrequent visits by tech support since it is an obsolute product.

Yes, I just have to keep looking for the cause. Apart from the random cutting it runs just fine.

stevieturbo
Forum Contributor
Forum Contributor
Posts: 3979
Joined: Sat Nov 18, 2006 6:22 pm
Location: Northern Ireland

Post by stevieturbo »

DaveEFI wrote:An intermittent fault like this means something is occasionally faulty, then clears. :D
If it didn't work at all, perhaps magnets would be the answer.
It might well be heat related - but at speed airflow would normally keep things cooler than at other times.

Intermittent electric faults are usually connectors, or a dry solder joint in the electronics.

If the tach input circuit on the Haltech is known to be iffy, I'd be inclined to fit a newer one. Add on twin input VR boards can be easily bought for MS, and are self adjusting. But you'd need someone who knows Haltech to fit one.

Of course it could also be a software glitch.

Really, you need to find out what the cause is before you can fix it.

Is there a Haltech forum you could ask on? It's very rare to have a unique fault.
There is a forum...given how old it is, I doubt he'd ever get much response.

Are you sure all triggering settings are correct ? Exactly what sensor are you using ?

Hall will be far more reliable than VR simply because no conditioning needs to take place and they are fer less susceptible to interference..
Looking at the instructions you should be able to use either NPN or PNP as it offers you an internal pullup on the input.

If you were getting no signal from a hall sensor....how were you testing it ?
9.85 @ 144.75mph
202mph standing mile
http://www.youtube.com/watch?v=XgWRCDtiTQ0

Post Reply

Return to “Electrical & Ignition Area”