Here's something I don't understand. 3 days ago our Panda - 2010 1.2 60hp engine Dynamic Eco - Failed to fire up on the first turn of the key. She always fires first turn after going over compression about half a dozen times. She cranked for at least twice as long before I released the key and tried again when she them fired up after just slightly longer than usual. Also she "stuttered" a wee bit before settling down to even running, probably due to a bit of excess fuel lying about? Mrs J drove the car later in the day and reported no problems but I doubt if she would know the difference as long as the engine managed to fire up eventually. Then she did it again the next morning when I went out to start her.

We both follow the same start procedure - Turn the key to the "run" position and wait for the padlock light to extinguish then turn it onwards to activate the starter motor. As the key is turned to the first position I always listen for the fuel pump running, which it did.

Yesterday though she fired up just as she always used to. I'm not sure why really but my mind is thinking it's more likely to have been an ignition problem because of the need she showed to "clear her throat" when she did fire up. I suppose it'll take a "no start" before I can really track it down as there are no DTCs posted at this time. Most likely a poor connection with the crank sensor being most suspect? Just wondering if this is a "known issue" and if so what's most likely to be the problem? Thanks to anyone who might like to speculate.

Our car has suffered a crankshaft sensor failure within the last two weeks, and the symptoms differed sightly from what you've described.

The reluctance to start sounds the same as in sometimes starts fine, sometimes cranks without firing.

But, when ours did fire there was no stuttering, she behaved fine as if there had never been a problem.

Then the engine would abruptly stall, and sometimes kick back in, sometimes not.

On these occasions, the tacho needle would drop suddenly to zero and the EML would come on (as the engine is effectively off, but with ignition on). When she started again, the revs would bounce straight back to normal and EML went off (until it stayed on permanently).

What happens with the rev counter when yours is stuttering? And does the EML come on? If your car abruptly stalls or revs drop to zero, this could indicate crankshaft sensor.

I would imagine your car has both crankshaft and camshaft position sensors? I understand cars with no camshaft sensor won't generate a fault code, it is the difference in signal between these that generates the fault code P0335 when the crankshaft sensor plays up, and surely this DTC would still be stored if this had been the case?

rmjbn1 said:

Our car has suffered a crankshaft sensor failure within the last two weeks, and the symptoms differed sightly from what you've described.

The reluctance to start sounds the same as in sometimes starts fine, sometimes cranks without firing.

But, when ours did fire there was no stuttering, she behaved fine as if there had never been a problem.

Then the engine would abruptly stall, and sometimes kick back in, sometimes not.

On these occasions, the tacho needle would drop suddenly to zero and the EML would come on (as the engine is effectively off, but with ignition on). When she started again, the revs would bounce straight back to normal and EML went off (until it stayed on permanently).

What happens with the rev counter when yours is stuttering? And does the EML come on? If your car abruptly stalls or revs drop to zero, this could indicate crankshaft sensor.

I would imagine your car has both crankshaft and camshaft position sensors? I understand cars with no camshaft sensor won't generate a fault code, it is the difference in signal between these that generates the fault code P0335 when the crankshaft sensor plays up, and surely this DTC would still be stored if this had been the case?

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Hmm, so let's try and remember. One thing for sure, once started she runs absolutely fine, just as she always has, no misfires.

Yes she has both cam and crank sensors. So should post up a misfire code? However when she fired up after these events she's not "misfiring" it's much more like when you put too much choke on in the old days of manual chokes and the engine "hunts" for just a second or too as it clears itself. Runs fine after that. When she's misbehaving there's not the slightest sign of life, it's just as if you're cranking with the ignition off. Then, in this instance, after cranking for the second time with no sign of firing, she just suddenly lights off, hunts slightly for a few seconds and settles down to running normally.

Regarding the dash display. Definitely no EML - which I suppose is consistent with no trouble codes being stored in the ECU? I don't remember seeing what the Tacho was doing as I wasn't really paying it any attention. However i think if it had been jumping around it would have attracted my attention as I was looking at the immobilizer padlock light to see if it was lit - it wasn't. Once running she continues to run fine, on the second occasion, after she fired up, we drove right across town and out the south side to my boy's house - a good 10 miles - and she never missed a beat.

Ah well, as I sometimes had to say to a customer, Just go on driving it sir and we'll see if something more definite develops.

rough running and difficult starting. I always look at the map sensor First


its one screw to undo


the eco seems susceptible to oil contamination

Thanks very much koalar. I've been looking at how MES displays it's equivalent of Fuel trims and having some very interesting and stimulating discussion with Grant at Gendan about it. Of course the MAP sensor often becomes part of these conversations. I've also seen several videos showing a vacuum pump being used to test Map sensors and I've long promised myself a vacuum pump! I've had trouble with MAF airflow sensors before on other makes of vehicle but never needed to look at a MAP before.

I know exactly where the MAP is and can see the screw that holds it in and just have never got round to pulling it yet. Interesting that you mention they are prone to contamination as I've seen others mention this too. I think I should pull it and give it a clean. Is this what it looks like when you've pulled it https://www.ebay.co.uk/sch/i.html?_...057.m570.l1313&_nkw=Panda+map+sensor&_sacat=0 With a MAF hot wire I'd start off giving it a good spray of carb cleaner and often that's all that's needed so with a MAP do you just spray the "business" end with carb cleaner or is it liable to be damaged by doing this? Also should I stick a bit of rag up the hole to clean it out too? Thanks for any advice you might like to give. - cheers, Jock

Pugglt Auld Jock said:

Thanks very much koalar. I've been looking at how MES displays it's equivalent of Fuel trims and having some very interesting and stimulating discussion with Grant at Gendan about it. Of course the MAP sensor often becomes part of these conversations. I've also seen several videos showing a vacuum pump being used to test Map sensors and I've long promised myself a vacuum pump! I've had trouble with MAF airflow sensors before on other makes of vehicle but never needed to look at a MAP before.

I know exactly where the MAP is and can see the screw that holds it in and just have never got round to pulling it yet. Interesting that you mention they are prone to contamination as I've seen others mention this too. I think I should pull it and give it a clean. Is this what it looks like when you've pulled it https://www.ebay.co.uk/sch/i.html?_...057.m570.l1313&_nkw=Panda+map+sensor&_sacat=0 With a MAF hot wire I'd start off giving it a good spray of carb cleaner and often that's all that's needed so with a MAP do you just spray the "business" end with carb cleaner or is it liable to be damaged by doing this? Also should I stick a bit of rag up the hole to clean it out too? Thanks for any advice you might like to give. - cheers, Jock

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yes

if its a problem it will have a blob of oil on the end. To clean make sure it pointing downward. the sensor is not sealed and you dont want any cleaner running inside. I have not cut one open to see if anything would get damaged, but probably not worth the risk

I will wait to see if its a problem First

to stop it happening again is a bit involved

here me cleaning the air filter pipe

seen this a few times now, but never on my older 05 and 06 cars

I sold Panda, now I have 500x, 1,6 etorque.
Before the sale I had to change the alternator because it was completely blocked.
The starter could not actually turn the motor.

Hi koalar, is that photo the underside of the air filter housing, where it connects to the throttle body?

Pugglt Auld Jock said:

I know exactly where the MAP is and can see the screw that holds it in and just have never got round to pulling it yet. Interesting that you mention they are prone to contamination as I've seen others mention this too.

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I cleaned the MAP with brake cleaner when I first got my car, it had quite a build-up of soot around the sensor.

I took it out to check 2&1/2 years later when my car started misbehaving recently and it was still clean.

Does your car have a fly-by-wire throttle, Jock? So no Idle Air Control Valve?

The only other similar symptoms I've had on my Panda was stuttering from a cold start during wet weather - turned out to be a plug lead slightly loose on the coil. Removed, cleaned and reconnected the HT leads and it hasn't happened again.

Pugglt Auld Jock said:

Thanks to anyone who might like to speculate.

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How much has it been used lately?

I'm wondering if the fuel may be getting stale; E5 hasn't got much of a shelf life, and E10 has even less.

Maybe try running a tank of super through it?

rmjbn1 said:

Hi koalar, is that photo the underside of the air filter housing, where it connects to the throttle body?

I cleaned the MAP with brake cleaner when I first got my car, it had quite a build-up of soot around the sensor.

I took it out to check 2&1/2 years later when my car started misbehaving recently and it was still clean.

Does your car have a fly-by-wire throttle, Jock? So no Idle Air Control Valve?

The only other similar symptoms I've had on my Panda was stuttering from a cold start during wet weather - turned out to be a plug lead slightly loose on the coil. Removed, cleaned and reconnected the HT leads and it hasn't happened again.

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From what I've been able to find out the car has never been owned by an "enthusiast" and initially was maintained by Arnold Clark somewhere in the midlands but then around year 4/5 it seems to have found it's way up here and service history becomes much more sketchy. I managed to trace the last garage that serviced it on the west side of our central belt who told me the gentleman who owned it was in very poor health and did very annual mileage. They were able to tell me that quite a bit was done to it just before he sold it - new sump and wishbones etc. As the chap is said to be in poor health I've not tried to contact him so I don't know how the car ended up for sale here in Edinburgh. There were lots of pointers to only intermittent use though. An old but clean looking air filter, a pollen filter which looked like it hadn't been changed in decades, loads of surface rust on the discs, and more. My guess would be that the old fella hardly used it for some time before I bought it. We've had her for over 3 years now and the way she ran steadily improved over the first year and she really runs pretty well now.

My engine is the older 60hp version with a throttle cable and IACV (which I'm very pleased to have - the throttle cable that is) The IACV may be playing some part in this but I doubt it as she runs and idles perfectly with the revs picking up when the air con kicks in just as you would expect. The only possible pointer to the MAP is that in the mid rev range - so around 2,000 to 4,500 if you floor the throttle she doesn't pull quite as strongly as she should - sort of "hangs back" slightly just like an engine running too lean. It's not a big effect and certainly nothing approaching a missfire. In fact Mrs J doesn't notice there is a problem at all and thinks I'm off my head but I know it does it which was why I'd been thinking earlier to remove the MAP and see what I could see. She cruises perfectly, very smooth, but if you hit an incline and press down on the throttle you get that same, very slight, withholding of power. Our old 999cc Panda Parade (1992) started doing the same thing towards the end of it's life and that turned out to be a slow responding O2 sensor. However Becky's shows a perfect graph trace using MES so I don't suspect it. I don't think any of this explains the intermittent starting problem - she's been behaving perfectly today, fired up almost instantly and took us down to Aldi. Then fired up beautifully again to bring us home with not a trace of a stutter at any time. By the way I took all the HT leads out and checked end terminals and sockets on the coils when I did the cam belt and it all looked to be in very good condition. I took care to push the leads full home when I reassembled it all but it might be worth me just checking again.

I think could waste an awful lot of time looking for the poor starting problem because it's so intermittent - and she does actually fire up so she's not stranding us - so I'm going to just leave it. I will be removing the MAP and giving it a clean though and maybe that'll give me more "pull" up Kirk Brae, a very steep and long hill on the way out of the city to see either of my boys.

jrkitching said:

How much has it been used lately?

I'm wondering if the fuel may be getting stale; E5 hasn't got much of a shelf life, and E10 has even less.

Maybe try running a tank of super through it?

Click to expand...

The car is very much a second car - and one of my main hobby activities. It does everything you shouldn't do to a car, goes local shopping. Takes Mrs J to the swimming pull and other short journeys. However maybe twice a month it goes out one of our boy's houses south of the city and then it gets a good run with the engine fully up to temperature and some faster main road running. It runs maybe 3 or 4 days a week but even so only does 2 to 3 thousand miles a year and during Covid it's probably only going to have done about 1,500 to 2,000 this year. She gets through a tankful of fuel around every 6 to 8 weeks - maybe less now with the restricted recent use?

An interesting thought about the fuel though - but wouldn't that affect not just starting? She's still on her last tank of fuel put in about a fortnight ago, so must be E5, and still only just below the full mark. Maybe we should be thinking about filling up to only the half way mark with the E10? The strange thing though is that this intermittent starting problem is very intermittent. I don't think she's done it more than about 6 or 7 times in total so if it was fuel quality she'd be doing it all the time, wouldn't she? I think I'm unlikely to track this one down until she starts doing it more often.

rmjbn1 said:

Hi koalar, is that photo the underside of the air filter housing, where it connects to the throttle body?

I cleaned the MAP with brake cleaner when I first got my car, it had quite a build-up of soot around the sensor.

I took it out to check 2&1/2 years later when my car started misbehaving recently and it was still clean.

Does your car have a fly-by-wire throttle, Jock? So no Idle Air Control Valve?

The only other similar symptoms I've had on my Panda was stuttering from a cold start during wet weather - turned out to be a plug lead slightly loose on the coil. Removed, cleaned and reconnected the HT leads and it hasn't happened again.

Click to expand...

Yes

Unless there is oil on MAP you can move on

I do a visual check. One bolt leaving the wire connected

It’s quicker than putting on a scanner. Which normally shows the wrong ambient temperature.

Soot is fine. Just move on to diagnostics

If there is oil mainly 68bhp model then it requires a clean of the pipes. New seal between the air box and T/B. Possibly a oil change also.

Pugglt Auld Jock said:

The only possible pointer to the MAP is that in the mid rev range - so around 2,000 to 4,500 if you floor the throttle she doesn't pull quite as strongly as she should - sort of "hangs back" slightly just like an engine running too lean.

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I've actually mislead you here by saying that the, albeit slight, "hanging back" effect happens at full throttle (foot flat on the floor) In fact this effect is noticed most in the mid rev range with large throttle openings but not absolutely flat on the floor. It actually pulls quite well with full throttle, probably because it's bypassing the fueling and timing modifications applied by the likes of the O2 sensor, MAP sensor, etc. As the O2 sensor signal looks Ok when graphed on MES I would guess a dirty MAP could cause this sort of effect. My reasoning being that as the inlet depression lessens due to the throttle opening the MAP signal should command the fueling to increase. If it's dirty it's signal may not be causing a sufficient increase in fueling?

Anyway I'm completing the repairs to my wee granddaughter's dolly's pram tomorrow. She managed to completely break the front axle away from the chassis and my friend - a demon welder - stitched it back on last night. Lots of plastic brackets etc had to be removed and the paint on the tubing has suffered burn back. So tomorrow I've got some rubbing down and painting to do and the brackets and plastic wheels to be refitted. If that all goes well I'll maybe get round to having a look at the MAP.

PS we did an Aldi shop today and she fired up absolutely fine.