We have a frustrating problem with my daughter's 1.2 Pop.

She has had the car from new since she learned to drive in 2011. I've offered to buy her a new car several times but she loves this one and wants to keep it.

All the time she has lived with us, or local to us, the car has been as good as gold. However, she moved up to London a few weeks ago and it now starts to throw a wobbly. Great!

She will be driving along at a pretty constant speed (70mph ish) for a few miles, then the MIL comes on, power starts to drop. Come to a halt, switch off engine, re-start and all is ok.

I've plugged in OBD reader software and no messages.

I have noticed a slight hesitation or 'miss' just about 1,700 rpm if you blip the throttle and then let the revs drop back to idle.

Any thoughts so far?




Now the really strange part.
Her journey from us back up to London is about 74 miles. On the way up the car has failed twice at exactly the same place (Thursley, just north of the Hindhead tunnel) about 35 miles into the journey. Ever odder, it has also failed on the return journey about 3 miles away from that same place! Again, around 35 miles into the journey.


Any ideas short of calling Mulder and Scully?

When was it last serviced?

D

AREA said:

then the MIL comes on
...
I've plugged in OBD reader software and no messages.

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I thought that illumination of the MIL always resulted in a stored Diagnostic Trouble Code (DTC), even if the problem is no longer present.

rallycinq said:

When was it last serviced?

D

Click to expand...

Serviced start of April including cambelt change.
Problem started about 4 weeks later.

Is servicing more likely to result in problems (e.g. sensors, wiring dislodged) ?


Re OBD - scanner isn't even picking up pending codes (those that happen before threshold met to make them a full blown error)

Needs a live scan while driving through Hindhead tunnel...

Although, crank sensor could be a culprit.

Cheers

D

Sounds like it's going into limp mode, though why there's no stored code for the light is a puzzle?

Rather than there being no code I'd say it's more likely the code reader can't read the car correctly. Pretty sure 99.9999% of the time EML means a fault code present.

Pathaleon said:

Rather than there being no code I'd say it's more likely the code reader can't read the car correctly. Pretty sure 99.9999% of the time EML means a fault code present.

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I would agree if the mil light is on there should be a code, new reader ?

My daughter has brought the car back for me to spend more time on...

Good news is that I've now have more info:
1) the MIL light flashes Orange when she has a problem (car 'feels funny' = if she stops, ignition off and on then MIL goes away and car is fine)
2) I've run scanner and have following error codes: P0300, P0302, P0303 and P0172

Before I delve in much deeper does this info ring any bells with anyone?

That's cylinder 2&3 misfiring and the engine is running too rich.

Pathaleon said:

That's cylinder 2&3 misfiring and the engine is running too rich.

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Indeed --- question is, "why?"

Old Ferraris, Lancias and Porsches I understand and can sort. These new fangled ECU things though !

;-)

A spark plug lead failed on our 59 pop causing a misfire(you could hear the spark jumping across and see it on no.4) £15 and all fixed, try new leads first and possibly plugs?

AREA said:

Indeed --- question is, "why?"

Old Ferraris, Lancias and Porsches I understand and can sort. These new fangled ECU things though !

;-)

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the probe is sensing over fuelling ( due to the misfire)

I'd do;

1, plugs checking for burn colours

2, leads - feeling for the "fit" of the ones coming off

a compression test if you've got the kit..

then test-run again.

I wouldn't expect anything major if switching off and back on "fixes" things


Grandes have a thing where the ECU sees differing timing signals after a belt-change.. , the ECU needs to be given an "alignment" to get things back in sync..
It's possible this is the issue..,

Charlie