Fiesta ECU

Hi, We have a Ford Fiesta 1.1 classic on a '96 plate, (these are apparently left over stock from '95),which failed the MOT on its emmissions. I bought a Draper fault code reader but it didn't flash at all. I have tried the FCR on a '95 Escort and it works fine. Is it likely that the car would still run with a faulty ECU? Does anyone know the diagnostic sockets connections at the ECU so I can meter the wiring to the socket? Cheers, Tony.

Reply to
Tony Wilkinson
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If the ECU is faulty, more than likely the car will not run.

Post your emissions test sheet results and we'll give you some tips in rectifying the problem, which on these CFi cars is usually one of about 4 easily fixable things.

Tim..

Reply to
Tim (Remove NOSPAM.

Why do you think the ECU is faulty? It's *far* more likely to be a sensor

- or something gummed up.

Reply to
Dave Plowman (News)

I presume the fault code reader "talks" directly to the ECU, since the FCR works on one car but not on this, I think either the wiring between the diagnostic socket and the ECU, or the ECU itself is faulty. I understand that the emmisions fault is likely to be a sensor, but it will be much easier to find the fault if I can read the ECU's fault codes.

Cheers,

Tony.

Reply to
Tony Wilkinson

"Tony Wilkinson"

If it's the 1.1 CFi engine, I read that even perfect working order they still struggle to creep through the emissions and need to be really hot during the test.

Reply to
Mark

Hello, Unfortunately it didn't just fail to creep through, it totally blew it. Here are the results:

Oil Temp 81 Pass

Fast Idle Test

RPM 2983 Pass CO% 6.058 Fail HC 444 Fail Lambda 0.852 Fail

Second Fast Idle

RPM 2908 Pass CO% 10.195 Fail HC 627 Fail Lambda 0.737 Fail

Natural Idle Test

RPM 908 Pass CO% 6.741 Fail

Do these results indicate a particular fault?

Thanks for all the replies so far.

Tony.

Reply to
Tony Wilkinson

Tony Wilkinson ( snipped-for-privacy@NOSPAMblueyonder.co.uk) gurgled happily, sounding much like they were saying :

You're not wrong about it "blowing it"...

The lambda's WAAAAAY out - so probably chucking a sensor in as a good (and cheap) place to start. Sounds as if the ECU doesn't have a clue what's going on in the exhaust, so the fuelling's all wrong as it tries to correct the lambda.

Reply to
Adrian

First of all ignore this post!

With a CO of 6% + you have an engine which is running severely rich. No amount of replacement O2 sensors will correct this, as the ECU only trims fueling by about 12% upon info from this sensor. If its been running this rich for long however the o2 sensor may well be carbon fouled and need replacing after you have solved the basic problem, which is most likely a faulty CTS, or connector.

I'm surprised you are not talking abou black smoke from the exhaust or single figure mpg 's!!

Tim..

Reply to
Tim (Remove NOSPAM.

For the uninitiated CTS = Coolant Temp Sensor. And looking at the figures, it certainly looks like the ECU thinks the engine is still cold. Try putting an ohm meter across the temp sensor with the engine cold, and check to see that the resistance drops as the engine heats up.

moray

Reply to
Moray Cuthill

Hi, The car is my Mums and she doesnt do many miles so I dont think she would notice the fuel consumption. I'll have a look at the CTS and its connector tomorrow. Thanks, Tony.

Reply to
Tony Wilkinson

Wow, it must think the engines freezing, is the temperature sensor connected?

Reply to
Duncan Wood

Thanks for the suggestions folks, I'll check the CTS tomorrow and report back. Cheers, Tony.

Reply to
Tony Wilkinson

I know what your up against.................. Give me back a 1.3 xflow. you could rebuild most of it in a day. Give me an alen keys and a set of feeler gauges, I like to set up my rocker end..

Paul Miller iEng MIIE (elec)

Reply to
Paul Miller

First thing I'd check is the airfilter. It sounds like a car which hasn't been looked after.

Reply to
Dave Plowman (News)

Personally, I appreciate the lack of stink from modern cars when out walking. Any older one which goes past is immediately obvious. The price to pay for this is tight control of combustion. Just not possible on a 'carb and points' engine. Now if only they could do the same to diesels.

Reply to
Dave Plowman (News)

Hi, Checked the CTS sensor today, it was open circuit. Will get a new one tomorrow, hopefully that should sort the emmisions problem. Thanks for all the advice. Tony.

Reply to
Tony Wilkinson

Crikey - I'm amazed it still ran. When this happened on my SD1 EFI, it wouldn't idle at all when hot.

It will certainly help. ;-)

Reply to
Dave Plowman (News)

I'll remind the Newsgroup of this the next time somebody says something about unreliable Ford engines!

Reply to
DervMan

Hopefully, otherwise you'll be needing new sensors...

Reply to
DervMan

Well, it's just that an open circuit sensor tells the engine it is cold, so sets the mixture for a cold start. Bit like pulling out the choke. And few cars would run on full choke when hot.

Reply to
Dave Plowman (News)

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