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2004 i-CTDI low MPG

replied to you Natasha, just take a read of the ECU software and send it over, I'll check it out for you. No point changing an ECU if it's mapped, I can provide a stock file if it has been tuned.
 
^ Fahad, a question on the ECU in the 7th gen diesel .... is it K-line or CAN-bus ?

(I presume it's CAN-bus, and I presume that is why it is easier to reload a map into it)
 
Nope it uses K-Line protocol to read write.. it's the Bosch EDC16. It can support Canbus as we can use canbus to flash BMW/VW/Merc with the same ECU in canbus but Honda have implemented the slower (but more stable) K-Line
 
Rather than go off-topic here, I'll ask more in the "Facelift ECU in pre-facelift?" thread.
 
Emailed you back... not sure if it's good or bad news. The file you sent is a 100% perfect match with two known factory software revisions (I checked two to be sure).

The map is not your problem... i would look elsewhere..
 
CAR WAS NOT MAPPED! :(

Do we have any other options left?

Just to conclude:
Engine was replaced with all components.
Since then I'm experiencing smell of diesel inside the car after driving at high speed. There are no other signs such as smoke or lose of power.

Any suggestions welcome.
 
No Smoke, No loss of power, performance is good..........hmmmmmm.

Driving at 90mph will hammer the mpg - down towards 30mpg, flooring the throttle in town like an idiot will kill the mpg, do both and you'll have a car struggling to get towards 30mpg.

If you're genuine do this......Fill the tank to the brim, reset the trip meter to zero. Drive the car around town like you're Miss Daisy driving on ice with bald tyres around town. On the motorway do the same, do not go above 70mph, do NOT take the engine above 2000rpm in town in any gear, town or motorway.

After you've done at least 100 miles, refill the tank to the brim, and calculate the mpg. And post your answers back here.

If you are still getting 30mpg (ish) then you have a hole in your tank!

Or.............You've got a hole in the petrol tank.
 
Smells could be due to all the disturbed oily parts and might need some time to burn off. If it starts instantly without any delay, then it can't be a fuel leak. Does it take more than a second to start ?

The low mpg after install might be due to the disturbance of the ECU, I thought that they had some kind of learning feature they need to build up to settle....

Maybe it just needs a bit of time to settle in..
 
Truthfully I haven't read through all the posts, but I would want to check:

MAF
MAP
EGR
Injectors (and calibration)
High Pressure Pump
Turbo Charger/actuator
Cracked Manifold or leaking exhaust
Blocked Cat

Trust me, it's not your ECU. There is nothing to suggest your ECU is faulty.
 
F6HAD said:
Truthfully I haven't read through all the posts, but I would want to check:

MAF
MAP
EGR
Injectors (and calibration)
High Pressure Pump
Turbo Charger/actuator
Cracked Manifold or leaking exhaust
Blocked Cat

Trust me, it's not your ECU. There is nothing to suggest your ECU is faulty.
Click to expand...
She checked all that, and then swapped the engine.
Only thing in common now .... is the exhaust and the ECU. Surely an ECU can be faulty, could be firing the injectors badly i.e. too many bursts, or bursts too long, etc, etc.

EDIT: she has the ECU from the swapped engine, but scared of swapping that as well, thinks the immobiliser behind the ignition switch will also need to be changed along with the transponder in the key. IMO the immobiliser is just a "dumb" device that transmits the code from key to ECU, so doesn't need swapping.
And so what if it does anyway, it must be easier to swap an ECU and immobiliser and key transponder than it was to swap an engine.
 
I exchanged emails with her, she said she's using a generic diagnostic tool. The car needs to go on a Honda HDS where the preset values inside the tool can check whether each component is operating inside the thresholds that Honda have set.

My money is actually on incorrect injector calibration or a weak/non genuine MAF.
 
MAF, MAP, Exhaust+Inlet manifold, Turbo, EGR, Cat. etc as well as complete engine with injectors was all swapped from a different car with no luck.

The only original part left is flap on inlet manifold. Could that cause the problem?

ECU - so can somebody give 100% explanation in how we try to swap it. Yes, it's easier to replace the engine for us than deal with ECU :ph34r: , cause we do mechanical repairs and try to avoid electronics as much as possible.

It's not exhaust manifold and not cat. as they were swapped as well

I have been on the proper diagnostic once but that has been on the old engine and I was mainly interested in injectors at that time. They said injectors are ok, but they did mention something about turbo not giving enough boost on high rpm. but turbo was replaced since then anyway.

If I have chance tomorrow we will lift the car on the ramp and try to search for a leak, as I don't like the smell of diesel inside the car. I have newborn baby and now this car is useless for me with that kind of smell. Is there is a chance that something can be leaking only on high speed? I know it sounds stupid, but anyway.

If there is no leak I will go to Honda garage again and will get them to do all possible checks.

So plan is as follows:
1. Leak
2. Honda Diagnostic
3. ECU Replacement
? Can flap on Inlet manifold be the reason?

BTW Fahad if we decide to remap the ECU would it be possible to go back if it's not going to work out?
 
I wouldn't want to remap a car that has potential underlying problems.

An ECU swap will require for the imo system to be paired with the replacement. I've never done it in a Honda, but have in a Nissan with NATS and it's a pig of a job. There are various modules across the car that need to be swapped as a complete matching set.

Again if you had a HDS system, I believe you can use it to recode an ECU to a donor car (although I've never used mine to do this yet).

I'm honestly not sure why anyone is thinking it's the ECU.

And what exactly is wrong with your MPG? what are you comparing it to? What is the full mileage range you are getting on a full tank and is the car a saloon or tourer?
 
Ok, so ECU swap is a bad idea, so we better leave it alone.

It's 4th Honda accord I have and it's saloon. Before I had 2005 (Sport), 2008 (Executive) and new shape 2008 (Sport) models all diesel. So basically I'm travelling same roads and distances every day to and from work. On all previous Accords I was getting about 600-660 miles per tank and this one it's around 380-420 miles. We did proper calculations before and it works out about 30 MPG may be even less.
 
I've mentioned this one before .... is it possible that the odometer is reading too low, that could explain low MPG.

Athough I don't know how an odometer could read low without the speed also reading low on mechanical instrumentation, is it possible for the odometer to be running differently from the speedomoeter on modern instrumentation ?

(I know that Natasha has said that she uses the car for the same journeys as on previous cars, but this is anecdotal and not scientific).

Just another wildcard to explain something that is getting more and more inexplicable. Maybe the car needs an exorcism.
 
Checked for leak today. We have some serious leak from exhaust manifold. That definitely was not there last week when were welding crack on that.

Any surgestions?
 
Natasha said:
Checked for leak today. We have some serious leak from exhaust manifold. That definitely was not there last week when were welding crack on that.

Any surgestions?
Click to expand...
It's a bit difficult to tell without looking! Hard to imagine that it isn't related to the manifold being worked on recently (I should think you took it off completely to weld the crack?), so I'm guessing that a gasket has blown?
 
The whole point is WHY DIESEL IS IN EXHAUST MANIFOLD???

My opinion is that engine is over-fueled and excessive diesel gets in exhaust. The question is still open WHAT IS OVER-FULLING ENGINE? If all parts has been replaced?
 
Natasha said:
My opinion is that engine is over-fueled and excessive diesel gets in exhaust. The question is still open WHAT IS OVER-FULLING ENGINE? If all parts has been replaced?
Click to expand...
My opinion too.

If there isn't an active device between the ECU and the injectors (I don't know if there is or not), then faulty ECU e.g. faulty circuitry causing extra bursts after the piston has gone past TDC.

Or maybe a fault in the loom, so that two cylinders are "paired" e.g. two injectors firing at the same time, so that each cylinder fires on the exahust stroke as well as the compression stroke. This reminds me of the Citroen 2CV, which fires both spark plugs at the same time i.e. the spark plugs fire on compression stroke and on exhaust stroke.

Just a hypothesis, I don't know how the power circuitry in an ECU would sustain itself in such a condition. But that hypothesis explains why there is not smoke, the ar is simply pouring diesel down the exhaust pipe, probably not enough to see/smell when idling, but certainly dipping out when the engine is under load. That's why I recommended doing an MPG test at steady 40 mph and an MPG test at steady 70 mph. You should see better MPG at 70 mph than at 40 mph. You could also try the car on a dyno and look at the exhaust.

As I say, just a hypothesis, but it does explain the facts you give us.
 
Natasha said:
The whole point is WHY DIESEL IS IN EXHAUST MANIFOLD???

My opinion is that engine is over-fueled and excessive diesel gets in exhaust. The question is still open WHAT IS OVER-FULLING ENGINE? If all parts has been replaced?
Click to expand...
BUT, MRS SHOUTY, YOU DIDN'T SAY IT WAS DIESEL, YOU JUST SAID IT WAS A LEAK!!!

How the devil do you know there's diesel inside the exhaust manifold anyway?
 
Jon_G said:
BUT, MRS SHOUTY, YOU DIDN'T SAY IT WAS DIESEL, YOU JUST SAID IT WAS A LEAK!!!

How the devil do you know there's diesel inside the exhaust manifold anyway?
Click to expand...
Mrs Shouty :lol:

There's probably neat diesel seeping out the cracked manifold :eek:

Natasha if you still have the old engine, take a look at the exhaust ports to see if there's any evidence of diesel in any port i.e. does one or more port look very different frrom the rest
 
freddofrog said:
There's probably neat diesel seeping out the cracked manifold :eek:
Click to expand...
But they welded up the cracked manifold! And they run a garage, so I'd ***ume it was done properly.

So if it's leaking then it's probably a gasket? But a garage is unlikely to fit these wrongly (and would at least realise they'd done it badly and so put it right).

So - if it's no longer cracked and the gaskets are OK - how can anyone know that actual diesel (not diesel fumes, mind) is getting into the manifold? Removal of the manifold for a second time hasn't been mentioned, neither has undoing the exhaust in order to take a look, nor anything else that would allow internal inspection of the manifold. Is neat diesel dripping out of the tailpipe?

I don't think I properly understand the details being reported, let alone suggest a likely repair... your previous suggestion of performing an exorcism might actually be an option?
 
I've stayed away from this thread for a while but, having come back to it, I see we're no further forward. Still, no proper diagnostics have been done - and I don't mean just a fault code read. Instead parts and a whole engine have been thrown at it but the problem persists. If proper diagnostics are not going to be done (ideally on HDS) then the best suggestion I can make is a gallon of petrol and a match!
 
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