The engine started, but then stopped!

[Ben Fung]

The engine has finally started but all too briefly. This is a new build with a Duratec and while it starts it wont fire without a little prod of the throttle and it stalls shrotly afterwards unless I keep the throttle in.

 

Now for the newbie questions. Are we supposed to adjust the throttle cable till the throttle is open enough for the engine to continue to idle? I thought it should just start on its own and idle. Is it just an adjustment that needs to be made or should is this odd behaviour from the engine.

 

Also there appears to be a little moisture being spat out of the exhaust, this is accompanied by quite a bit of black grit or soot. Is this normal for a new engine?

 

Lastly the oil pressure seems to sit at about 6bar - is this normal?

 

(the battery was discharged diagnosing an earlier fault but was left charging overnight, so while it is running a little low, I don't think this should be too big a deal unless someone can tell me otherwise).

[Stationary M25 Traveller]

The cable should have a tiny bit of slack when throttle shut. The butterfly should be closed. Definitely don't adjust the cable to open it !!! 😳

 

Quite normal for water and soot to be spat out of the exhaust.

 

Oil pressure sounds quite healthy - it is a new engine. My old (30,000 mile) k-series starts at around 4.5 bar, when hot and idling it falls to 2 bar, but 4 bar on throttle.

 

Can't tell you why it won't run - but someone will be along soon.

 

 

[Ben Fung]

Could it be a possible issue with the IACV/throttle position sensor? The sensor was replaced because the original ones retaining clip had snapped. Is there a position that the rotating sensor needs to be in other than just mated to the spindle on the IACV?

[CageyH]

Try the reset of IACV/ECU procedure (if one exists for the Duratec).

 

Only dead fish go with the flow....!

 

Edited by - CageyH on 28 Feb 2009 16:50:00

[Ben Fung]

Any ideas on how to reset the ECU or if it's possible n the Duratec? I did a search and found this post http://blatchat.com/t.asp?id=147752 I tried the five prods of the throttle method but I didn't get the buzzing/clicking. Guessing there might be a different way to reset it.

[Gordon C]

Worth a little read through this. Whilst you might not have an Alpha Engine Management system installed it will certainly give you a few pointers in setting up throttle bodys etc. Food for thought.

 

You say she only runs with a little throttle applied. Worth looking at the butterflys then. Should have a little gap at the bottom. If it doesn't you'll not get the all important airflow through the intake manifold.

Further to that the throttle postion sensor may need a tweak one way or tuther to get the revs up for starters. Once the engine is then running you can then start to balance things out between the bodies, adjust idle speeds etc

For the balance side of things you'll need a syncrometer. Reasonable price on ebay if you need one.

 

Might have nothing to do with you problem however i mention it because i was setting up my xflow SS only last week following a head rebuild. Alpha Plus Engine Management / throttle bodies & injectors installed. Following a very cagey start she just wouldn't stay running to start with. Then got her to run albeit roughly. Following the above guide i have now balanced, adjusted idle speed and have a good CO reading.

 

Just a thought.

 

_________________________

Gordon.

[CJS]

Ben, did you get it sorted?

 

I had an issue that sounds similar on my recent build - R400 (Duratec). The engine would promptly die without the help of a little bit of throttle and would (when given more throttle) cough and splutter. Turned out the engine loom, and the replacement loom from Caterham, were faulty with breaks in a couple of places (including the 5v line to the TPS). Took the local distributor (I live in Dubai) a month to diagnose and get it all sorted. Maybe you have a bad one too?

 

Once fixed the engine idles without adjustment to the throttle (i.e. no need for adjustment to hold it open a little). The TPS on mine is a sealed unit too - no adjustment possible.

 

Anyway, good luck.

 

Chris

[Ben Fung]

Thanks for all the replies, unfortunately this is still going on. The R400 is running a plenum chamber as opposed to the throttle bodies so adjusting the butterflies wasn't really something i could do rather I could only really put more tension on the throttle cable, which didn't sound like the right thing.

 

I missed the obvious method of resetting the ECU being to unplug it and leave it without power for a minute before reconnecting it so I'll have to try that. "Have you tried rebooting it?"

 

Chris - thanks for the advice on the TPS/Loom problem, I saw your post earlier and checked the plug. It seems I've getting the 5V on the outer pin and just under 5V from the middle pin so connectivity to the TPS looks OK. Different positions of the spindle on the TPS didn't seem to make a difference either - not that it was even adjustable.

 

Just spoke to Chris at Caterham and he's advise loosening the Idle Bypass Screw (a grub screw somewhere apparently) which is on the plenum but I don't seem to remember seeing one, guess I'll have another look tonight.

[Ben Fung]

OK so adjusting the grub screw didn't work and neither did disconnecting the battery for a few minutes to reset the ECU.

 

Would this coils in the wrong order generate these kind of symptoms? ie won't start without throttle application, won't idle and stalls? It's slso quite spluttery too when it starts with throttle applied)

 

I looked at the wiring diagram but the colour of the wires don't seem to match what is attached to the coils.

 

Is there another way I can confirm its firing in the right order? And this might be really obvious but and I haven't noticed which cylinder would be cylinder #1 on a Duratec?

[Stationary M25 Traveller]

No. 1 should be at the front of the car.

 

 

[akakubi]

A wild guess, but could it be that you were sent a wrong/faulty ECU of MFU? There were many bits missing in my R400 kit when I was building it.

 

One annoying bit was the missing fuel pump cut-off diode (something) near the MFU. The pump would not prime without it. Spent six hours tracking down the problem as the manual failed to mention it at all. But when I called to order it the CC mechanic said that the MFU or ECU could be faulty as well. Neither was on mine luckily, but you may want to ask.

 

Edited by - akakubi on 3 Mar 2009 14:35:39

[CJS]

Ben,

 

This sounds exactly like the issue I had. I'll try to find out more details of the solution from the workshop that sorted my car. One thing they did mention was that the firing order was wrong at some point (this may have been their doing though to be fair to CC).

 

Chris

[CJS]

Ben,

 

I hope you've fixed the problem making this post otise, but if not this is the explanation I received, when asked to help you, from the regional (ME) Caterham distributors that fixed a similar sounding issue with my newly built but poorly car:

 

"We were fighting with 2 problems at the same time. The original wiring loom had a fault with the 5 volt feed to the sensors which caused the over fuelling and running issues you had at build. We then replaced the loom and the car would start - run and then die after 20 sec then not restart. When the cam position sensor was disconnected it would fire once and then flood up - blip the throttle to give the TPS an input and it would run although very roughly. The problem we had was the cam position sensor polarity wiring was back to front in the new loom and while carrying out tests we managed to get the plug leads crossed which cost another hour of confusion!

 

The ignition system uses a sequential spark and injector system, if the ECU looses the cam position sensor it defaults to wasted spark system ** as it only has the crank position sensor to use as reference for where each piston is and when to fire each cylinder. On a 4 stroke engine the crank does 1 revolution to the cams 2 revolutions so it loses the ignition timing without the cam sensor. After we corrected the polarity of the connector it would only run with the cam sensor disconnected as by this time we had the plug leads in the wrong order (if you take off your carbon cover you will see the loom to the coil packs fits perfectly in the reverse order and not so nice in the correct order!). Because it was firing the wasted spark system without the cam position sensor it would run but not as smooth as it should, when we reconnected the cam sensor the engine would die instantly as it reverted to sequential spark. We then spotted our mistake with the plug leads and off she went!

 

Hope this helps, it a highly condensed version of a huge amount of head scratching and testing that went on.

 

**(it sparks 2 cylinders at the same time, one spark is on a compression stroke which fires the other is on exhaust stroke and does nothing hence the term wasted spark)"

 

Hope this helps in some way if it's not already sorted. As is mentioned above it took a long time to get this sorted; over a month of headscratching and to-ings and fro-ings between them at Caterham. That's electrical issues for you I suppose.

 

All sorted now though and the car is going great!

 

Good luck

 

Chris

[Colin S]

I know this sounds stupid but how much fuel do you have in the tank. My Duratec wouldn't run until I had put 10 litres in. The book says 5 litres but the book is wrong.

 

Ignore me if if it's something you know.

 

Colin

[Ben Fung]

Chris - Thanks for digging up that info for me, certainly sounds like quite a saga you endured. Glad to hear all is going well now.

 

Akakubi - I hope not but I've mentioned it to them

 

As for fuel had around 30L in the tank so we could rule that out too - plus fuel is getting into the cylinders quite happily.

 

The other stuff I tried was

- Checking for 5V on TPS

- Starting without TPS

- Sacrificing a goat

- Starting without crank sensor

- Starting while manually manipulating TPS spindle

- Reversing TPS

- Dancing a little engine start jig

- Different idle bypass screw settings

- Double checked the spark lead order (that took a while, wire colours didn't match)

- Sacrificing another goat

- Resetting ECU and crossing fingers in between all these steps

 

Still no luck! After troubleshooting this over the phone with Chris Weston at Caterham he thought it best to just trailer it up and let them sort it out at post build this week.

 

So CC have had it a couple of days now and still getting to the bottom of it. That means its out of my hands now but I'll be sure to update the post once they come up with the solution.

 

Thanks for all the help guys, I've really appreciated all the suggestions. 😶‍🌫️

[TheManAlive]

Well, there's your problem. Bleedin obvious when you think about and so easy to fix. If only people would read the blooming manuals.

 

It says quite clearly on page two eighty two of McGuffin`s 'Ninety-Three Easy Steps to Alinement With the Cosmic Deities', that a spluttering Duratec is a THREE goat job. Two just wont cut the mustard. It also says that if you dont strangle a four year old chicken before firing her up for the first time your mpg figures will be crazy!

[Ben Fung]

My kit only arrived with the two goats and Halfords were out of stock, I'll be sure to keep pick up an extra one next time they go on sale guess you never know when one might come in handy. Guess it'll save of the upkeep of the front lawn too.

 

Now should I choke the chicken 😳 pre or post SVA? I want to make sure I get past emissions test.

[John Vine]

On a 4 stroke engine the crank does 1 revolution to the cams 2 revolutions

Surely it's the other way round?

The book says 5 litres but the book is wrong.

Perhaps CC have now corrected this, as my Assembly Guide (Sect 14, para 26) clearly says 15 litres.

 

JV

[Ben Fung]

Woohoo! They've resolved the issue and I just picked up the car this morning for a lovely sunny maiden blat. The fix was just tweaking the ECU so nought to be done by me. Glad it wasn't anything I missed.

 

Thanks for all the suggestions. 😶‍🌫️