[jerry can]

I've often read about this strange issue with the 1.6 Duratec engined Ford Fiestas and Fusions where occasionally on cold starts the Engine Check/Service warning light would come on and the throttle would become unresponsive. Switching off and restarting the engine was the most common 'solution' that people found to work most of the time.
Since November i too was introduced to this annoying and rather worrisome issue on my recently acquired Fusion 1.6, and as the Delhi winters set in it became a daily morning exercise, sometimes requiring multiple restarts. Ford service as usual had no real solutions other than huge estimates for multiple sensor replacements et al. So i decided it was time for some hard thinking. There were a few clear givens:

1. It's a cold-start issue. So that ruled out a lambda/oxygen sensor issue as a cold engine running on choke bypasses the Lambda/oxygen sensor.
2. Can't be Intake leaks as the problem disappears when the engine warms up.
3. On cold starts immediate high throttle (>4k rpm) often prevented the issue from occurring. But its not good for the engine at all.

Thus, i figured it could be an air flow issue but not a leak. It could also be temperature related. Somehow the ECU was getting wrong info about either the air flow or the air temp and either over compensating or not compensating for the actual conditions. And AFAIK the 1.6 Duratech has a MAP instead of MAF sensor, it seemed a likely enough culprit here.
What's a MAP sensor?
The MAP or Manifold Absolute Pressure Sensor measures the absolute pressure in the intake manifold and compares it with a reference vacuum to enable the air mass to be precisely defined.
It then sends the appropriate voltage signal to the vehicle’s computer which decides whether to increase or decrease fuel supply to the engine and adjust spark advancement accordingly. Issues with MAP sensor can lead to various problems from excessive fuel consumption, miss fires, erratic idle, reduced engine performance, etc. A malfunctioning MAP sensor will almost always also result in the Engine Check warning light to come on. And before I start appearing like some amazing engineering whiz, i'd like to confess here that a lot of this is info gathered from various sources on the indispensable world wide web
Thus, I set about locating the MAP on the Fusion engine and to my horror discovered that it was almost inaccessible, buried deep beneath the Air Cleaner Outlet Pipe! The Air Pipe would have to be removed to access the sensor - not an easy job, especially the 'putting the pipe back on' part, as the Ford clamps that tighten the pipe ends are the clip types and not the screwed on ones. It was time for professional help and so, armed with all this info, a good Electrical Contact Cleaner spray, and a by now obsessive zeal I headed to my local mechanic.
The subsequent process of removal, cleaning and the results i am describing below:

The engine bay


Location of the MAP sensor and Throttle body


Close up of the Throttle Body and MAP sensor location, with air outlet pipe removed and the MAP also removed. Sorry the pic of the MAP sensor while it was in position didn't get saved.
Also notice the dirty throttle body. I spray cleaned it as well.


The MAP sensor (reference image). It fits in the above shown location with a single Torq screw, and the connector fits on the other end.


The MAP sensor up close


Top view. The sensor part, we cleaned this with a healthy dose of Electrical Contact Cleaner spray. It's very sensitive so do avoid touching the inside part.


The Cleaner


The Result:
I cleaned the sensor and the Throttle body, allowed them to dry for some time, and then put everything back. I started the car but felt no immediate difference in idling or performance. But the engine was warm at that time so no chance of checking for the dreaded warning light. Also it would take the ECU a while to adjust to the changes so no immediate perceptible difference in idling or performance also.
Next morning, it's 7 degrees C. I walked gingerly to the car and after a bit of a finger crossing moment, fire her up... And... no warning light! I waited but nothing at all. she was idling normally, sitting there ready to pounce
It's been 8 days now and the mercury has plummeted here, in fact it's 4 degrees C outside right now, but every morning she just starts like new and not once has the dreaded engine check warning come on, nor has the accelerator pedal become useless. The MAP sensor cleaning seems to have done the trick, and I'm keeping my fingers crossed.
I hope this is of use to those of you grappling with this issue since a while, it's fixed mine and i hope it fixes yours too. At least it's worth a shot.
Do let me know if you need any further clarifications. I'll also keep updating the thread as and when any new developments occur.

_

[vnabhi]

Fantastic revelation! Many thanks. I have been having the same symptom of the early morning engine/drive train warning light since last winter, but only when ambient temperature is below 22 deg celsius, which is rare in Hyderabad. So far the symptom vanishes after switching off and then on again. So I have decided to live with it, as it has happened only 5 times in the previous winter, and 3 times this winter. I wonder why Ford A.S.S has not been able to analyze this from the winter angle, that I'd suspected a year back (details in my LTO thread)

I wish you'd had a pic of the MAP sensor in position, after removing the air intake hose pipe. In any case, I might give this a try if things get worse.

I have a few questions for you:-

1. How difficult is it to remove and put things back in place? Which is the most tricky part?
2. How much does a new MAP sensor cost?
3. Can you please define 'erratic idling'? I'm asking because a year back, after a high-speed team-bhp drive, I switched off at a dhaba. But when I switched on again to park in a better place, I found the tacho moving from 800 rpm to 1400 on and off without any throttle input! This apart, last night, in bumper-to-bumper traffic, whenever the car came to a complete stop, the car was shuddering, but it vanished as soon as the car started crawling. I was thinking of fuel quality, but not sure.

[Jeroen]

Very good story! Thanks for that.

MAP sensor seems to be a known culprit for this sort of problems.

On many modern cars just cleaning items like throttle body, MAP (or MAF) and the respective electrical connectors might cure a lot of eratic behavior.

If it still does'nt solve take it to the dealer and ask them to read the codes. Or invest in a OBD scanner yourself. I have several and I have found them extremely useful in trouble shooting modern cars.

On the reving 800 - 1400 rpm; I've owned and still own a Fiesta and this has happened on all of them at some point in time; Usually related to the idle control valve (or whatever Ford calls it these days). Not sure on the latest engine version, but on all earlier model it's a valve (on/off or with a step motor) somewhere in the inlet circuit.

Jeroen

[vnabhi]

Originally Posted by Jeroen

On the reving 800 - 1400 rpm; I've owned and still own a Fiesta and this has happened on all of them at some point in time; Usually related to the idle control valve (or whatever Ford calls it these days). Not sure on the latest engine version, but on all earlier model it's a valve (on/off or with a step motor) somewhere in the inlet circuit.

Jeroen

Many thanks. But did you do anything to cure the issue with the idle control valve, or did it cure itself on its own? I've had that symptom only once so far.

[Jeroen]

Depends, I've had just about every variation.
Once I managed to fix it by just cleaning it rigorously, once I seem to recall I had to replace an o-ring and once I replaced the whole valve. Can't remember what it cost, but it wasn't very expensive.

One of my other cars, an Alfa Romeo Spider, suffers from the same problem, especially the series IV. Actually, on that one I just pull the electric connector off. Cars runs fine, might be a bit more tricky to start when cold.

Jeroen

[dhanushs]

Hi,

Can you please let me know what was the fault code you were getting?

[Jeroen]

Wish I could, but this was before I had my various OBD scanner I currently have.

In all honesty, hunting can also be caused by the MAF, faulty O2 sensor or just an air leak on the air intake somewhere. An OBD code reader will tell you.

But again, easy test, just disconnect the Idle valve and see what happens. If it stops hunting you have most likely found your culprit, if not keep searching. My next item would be an air leak somewhere. But again, these days I have several OBD readers so that helps. Now I'm not sure what a generic OBD reader would give you for these sort of troubles of whether you would need a make/type specific one.

Jeroen

[Jeroen]

Thought I'd check my OBD manual; here's what it says for Ford specific OBDII codes:

P1504 Idle Air Control (IAC) circuit malfunction
P1505 Idle Air Control (IAC( system at adaptive clip
P1506 Idle Air Control (IAC) overspeed error
P1507 Idle Air Control (IAC) underspeed error

The above comes from the Haynes OBD-II manual & Electronic Engine Management Systems. It is specific for OBDII, hence the US market. I'm not sure what OBD system is used in India. Is it the European variant?

As a matter of fact, I'm in my home country the Netherlands. That's why I have access to my manuals, as I did not bring them to Delhi. But a few days ago my next door neighbor and me were chatting about our cars and OBDs and we run all my American OBDII scanners on his very European Opel which has EOBD. As far as we could tell all scanners ran fine and gave correct readings. So I assume the above codes would be good for India as well

Good luck,

Jeroen

[jerry can]

Originally Posted by vnabhi

1. How difficult is it to remove and put things back in place? Which is the most tricky part?
2. How much does a new MAP sensor cost?

Hi @vnabhi; sorry for the delayed response, it's not very tricky at all. The only thing to careful of is to take off and put back the Air Outlet Pipe. It's got metal clamps on both ends but these unlike Japanese ones don't have screws but are tightened with tension clamps. You have to use needle-nose pliers to loosen these and then tighten them back. It's this part that's a bit tricky as you don't want to leave them loose. In my case we didn't loosen them much, though putting them back on without opening the clamps was a little tough but we managed in 15 min.
Once you take off the pipe you'll be able to see the MAP sensor, it's got a connector with wires attached to it, you'll first need to pull out the connector carefully and then just unscrew the one Torq screw that holds the sensor in place.
I checked with Ford and they said a new MAP sensor would be around 8 or 9k.
.

[ghodlur]

@jerry can

A quick question
What was the reason for the gumming on the MAP sensor in your car? Does it have any rubber O ring or something to hold the sensor and gum formation must have been due to heat?

I mentioned the same to the Ford SA during the recent servicing of my Fiesta and the blank look on his face said it all. Unfortunately I had gone on a Sunday when most of the knowledgeable SA's take an off. Hence could not get an answer.

[jerry can]

@ghodlur; from whatever i have gathered most deposits are from oil and combustion gases transferred from the PCV (crankcase ventilation)system and depend on the quality of fuel, the worse the quality more the deposits. Some deposits can also form if there's a leak in the intake hoses. In fact, in places where the fuel quality is bad, most experts recommend cleaning the MAP sensor at once a year.
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[vista_qjd]

The problem you have described is very similar to what i am facing in my Vista. Everyday morning the engine light comes and vanishes in 5 minutes, only to come back next day morning. I have it described in the link below:
http://www.team-bhp.com/forum/techni...ml#post3010462

I think with this info you have provided, I should probably have the MAP cleaned up.

[jerry can]

Originally Posted by vista_qjd

I think with this info you have provided, I should probably have the MAP cleaned up.

Yup your problem seems similar. It's worth giving this a shot, also try getting the throttle body cleaned as well. Good luck

[vnabhi]

@jerry can---when you 'cleaned' the map sensor and throttle body, did you just spray that cleaner on both and let it dry, or did you clean with a cloth also?

Sorry for bugging you with so many questions.

[jerry can]

@vnabhi: I sprayed the MAP sensor, then waited for a couple of minutes for it to dry then wiped the outside with a lint-free microfibre cloth. The inside part is the actual sensor and i didn't want to damage it so didn't wipe it, just let it dry completely.
As for the Throttle body, i sprayed it with throttle body cleaner and wiped the outside with the microfibre. You check out a few videos on youtube to see the process of spray cleaning the throttle body without taking it out.
Feel free to write in if you have any more queries, i'm happy to be of help

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