Mk6 Fiesta in Limp Mode

snips86x

snips86x

snips86x

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My '02 Mk 6 1.4TDCi has gone into Limp mode showing 'EAC fail' on the dash. The i've got diagnostics booked for 8AM tomorrow morning (£24) but being a non-ford dealer, they cannot update.

The earliest I can get an update (assuming one is available) is on the 29th which means I have to drive my car in this state for a week.

I know the EAC Fault can relate to a number of things, but I don't really have a choice and without knowing the actual fault, its hard to gauge additional damage.

Do you think it would be OK to drive? I've got no mis-firing issues and I've disconnected the battery for 2 hours which made no difference.
 
Do you think cleaning the throttle body would actually make a difference? I know without the code its hard to know what the exact issue is, but still!
 
Last edited:
troops said:
Apparently the throttle body is a common fault on that engine.
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Yes, but its not quite a throttle body apparently, its an air shut off.Either way, mine is as clean as a whistle so it could be something else.

The wiring loom and acceleration pedal electronics have been mentioned before. I guess I'll have to see what the diagnosis comes up with tomorrow.
 
The 1.4TDCI Duratorq is actually a PSA (Peugeot / Citroen) unit. I don't know if they come with an air cutoff valve. Which is really only useful to prevent runaway. By the amount of French diesels I've seen on Youtube going into runaway, I'd wager they don't have an air cutoff valve.

The EGR valve on the other hand, is the one that gets bunged up with crap on diesels.
 
OhEsEcks said:
The 1.4TDCI Duratorq is actually a PSA (Peugeot / Citroen) unit. I don't know if they come with an air cutoff valve. Which is really only useful to prevent runaway. By the amount of French diesels I've seen on Youtube going into runaway, I'd wager they don't have an air cutoff valve.

The EGR valve on the other hand, is the one that gets bunged up with crap on diesels.
Click to expand...

Yes, I felt slightly cheated when I found out, but it has been sound so no real issues with their engines!

OhEsEcks said:
Came across this which should give you some info: http://www.justanswer.com/uk-ford/4ujrq-fiesta-eac-fail-light-came-losing-power-local-garage.html

I've also seen a couple other posts pointing out dodgy connections being the problem.
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This is what every other forum has been saying, on previous threads, that its down to the code which really helps determine the issue. Hopefully tomorrow will provde fruitful.

I had the injector seals replaced a few weeks back, will get getting the garage to fix this if its related!
 
Here are the results of the diagnostics:

263bqeg.jpg


What does it mean?

The garage have cleared the codes and the car drives as it should, which is really nice!
 
The first one "circuit low input" would make me think that there's a problem with the voltage being supplied to the fuel temp sensor. If that's "permanent" then despite code clearing, it'll probably be back soon.
http://engine-codes.com/p0182_ford.html

The second one, again I would think is down to a problematic connection.
http://engine-codes.com/p0571_ford.html

The last one is possibly the one causing the car to go into limp mode. Diesels work by regulating fuel into the cylinders. Put your foot down, more diesel is injected. Take your foot off, less diesel is injected (hence no need for a throttle body, insofar as I understand it). If there's a dodgy connection or wire between the engine and the pedal(s) that is breaking or reducing voltage this could possibly be what's causing it to go limp.
http://engine-codes.com/p0002.html

The P0002 is a generic code and you'll probably need to go to a Ford garage to get a proper diagnostic done.

But I'm guessing, based on what I was reading yesterday and the link I posted above in an earlier post, that it is mostly down to electrical connections being iffy. Despite code clearing, those faults will probably be back if the connection between pedals and engine need looking at.
 
Oh wow, thanks for the update, that really help - well, to a degree!

Do you think using an electrical cleaner spray could stop it going into limp mode?
 
snips86x said:
Oh wow, thanks for the update, that really help - well, to a degree!

Do you think using an electrical cleaner spray could stop it going into limp mode?
Click to expand...

It may be that the contacts on the PCM connectors are grubby, so that's causing loss of voltage or complete shorts, so could be helpful. If pin contacts have started to corrode, that might be a bigger problem and possibly require a replacement connector.

It may also be that the wires into the PCM connectors are loose / broken and shorting, producing those codes. This will require an auto electrician to strip back wiring and look for problems.

It may also be something failing and dropping signal back to the PCM/ECU completely. It could be that the fuel temperature sensor (the first error listed) has failed. If it was something like an injector failure or problem you'd notice because the engine would idle roughly. A temp sensor failure I have no idea what the symptoms would be. But as they're for emissions / economy, I suppose the car could throw itself into limp mode if it doesn't know the temperature of the fuel it's injecting into the cylinders....

This is, of course, all guess work (but something I'm interested in as I also own a diesel Ford [Focus C-Max]).
 
Thanks again - well I'm looking to change my car in light of this issue and since its gone away, it may be the best opportunity!
 
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