As part of the various steps I've tried so far, I pulled the throttle body off and cleaned it thoroughly with isporopyl alcohol, and noticed that the alcohol pooled on the throttle plate rather than dripping straight through, so I'm hopeful that's reasonably airtight. Plugs should be good as only a few months old, but I'd wondered about leads, so have put them and coils are on my list of possible future items to change.
Technical Jerkiness on light throttle, esp when cold.
- Thread starter PacoJones
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Technical Jerkiness on light throttle, esp when cold.
Nobody is talking about the affect air/fuel mixture
I thought we already knew the problem, the MAP is covered in oil
When the MAP is cleaned the car works fine
The breather system works via vacuum
The original poster has two leaks one here
And one here
Unless the pipes are clear and properly connected, you will be for ever cleaning the MAP sensor as oil dips into the inlet manifold and fill it with oil
If the system is working properly the MAP should not get covered in oil, assuming the rest of the engine is okay
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They couldn't confirm measurements so ordered it anyway - and it's identical in size to the first one that was too small! But they'll give me a refund.
I'll just cut to the chase and pay for the overpriced one with the correct part number in a few days time I think, and see how it drives in the meantime. Will report back when correct sized seal has been purchased and fitted.
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The air filter rubber seat will have zero effect on oil in the inlet manifold. All breather pipes must be externally dry and MAP sensor should be clean.
If the MAP continues to oil up, its likely you have glazed cylinder bores caused be excess slow driving. The usual cure for that is some long (more than 100 miles) motorway drives where you go properly fast and work the car hard. It will free-off but it takes time.
If the MAP continues to oil up, its likely you have glazed cylinder bores caused be excess slow driving. The usual cure for that is some long (more than 100 miles) motorway drives where you go properly fast and work the car hard. It will free-off but it takes time.
Are you sure the crankcase breather works on vacuum
When I had a problem with mine oiling up every month or so I fixed it permanently
If it's less effective, due to leaks it gives the oil time to separate out
As I have already said there maybe another cause, but let's fix the two problems we can see first
But glazed bores is not a common issue on these cars, and slow driving is not the cause, mainly effect new or rebuilt engines
I have no idea what 100 mile of driving properly fast on a motorway is supposed to achieve, the only fix is to hone the cross hatching back
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Hard use of my Seicento 900 sorted out similar symptoms. Ditto my Brother’s 2004 Panda 1.2. Both were low miles of almost entirely town use. ”Proper” use free’d up the engines and they shopped using oil.
I may be wrong about the breather pipe connection but I see no point in stressing about the air filter seal. Unless it’s split of course. It will not affect the hesitation at low speeds.
I may be wrong about the breather pipe connection but I see no point in stressing about the air filter seal. Unless it’s split of course. It will not affect the hesitation at low speeds.
Mike1alike
Established member
What did you do there? You put a cloth in, or what is that?!
Basically it like sucking on a straw
If there's bits of ice suck up the flow isn't great
Yep I push a long handle screwdriver down the small pipe and rags down the rest
Back to the straw if there a hole in the side of it does not work as a straw
The ends of the breather pipes have to be a nice fit, as does the seal between the airbox and throttle body
Even a fairly worn out engine does not oil up the MAP sensor, I had two high miles one just under 200K miles one just over, they weren't well looked after or serviced
There is a service bulletin for the pipe, although manly for smell
109/03/2011./.Various Fiat Models10All 1.2 8v and 1.4 8v models, excluding LPG and methane versions - Idea, 500, Panda, Grande Punto, Punto Evo, Linea, Doblò (119 / 223)33.101080 1 581 BCOIL VAPOUR RECIRCULATION PIPEEngine oil vapour recovery pipe (blow-by) deterioration - Service Solution
Cancels and replaces SN 10.33.10 of 10/11/2010. |
Also vacuum leaks is also on of the many, many things asked to be checked here
101/06/2012./.Fiat various models10Version: 500, Panda (169) and Grande Punto with 1.2 8 V and 1.4 8/16 V engine29.121048 0 000 AAENGINE STARTINGLong/difficult starting and/or irregular idle - Network Information
FAULT COMPLAINED OF
Long and difficult starting and/or irregular idling.TECHNICAL CAUSE
Fouling of the combined sensor and of the intake ductThought I'd come back and round up this thread.
Problem was much improved with the actions noted above, but still the odd kangaroo petrol scenario on light throttle in 2nd gear when cold.
Finally bit the bullet and forked out a ludicrous 28 quid inc postage for the rubber ring that seals between the airbox and the throttle body. Part number is 46528828 and it was an oem replacement part at least.
On the plus side, the problem now appears resolved - have driven it a few times since fitting the new seal and have tried to provoke the issue each time while cold and so far, all good. So 28 quid well spent, even if I didn't think so at the time!
I've ended up with an unneeded brand new seal for a Doblo 1.2 (p/n is 71748095) as the supplier refunded me but didn't want it back when it didn't fit, so if anyone can use it, it's yours for whatever the postage costs.
Thanks everyone for your input, especially @koalar
Problem was much improved with the actions noted above, but still the odd kangaroo petrol scenario on light throttle in 2nd gear when cold.
Finally bit the bullet and forked out a ludicrous 28 quid inc postage for the rubber ring that seals between the airbox and the throttle body. Part number is 46528828 and it was an oem replacement part at least.
On the plus side, the problem now appears resolved - have driven it a few times since fitting the new seal and have tried to provoke the issue each time while cold and so far, all good. So 28 quid well spent, even if I didn't think so at the time!
I've ended up with an unneeded brand new seal for a Doblo 1.2 (p/n is 71748095) as the supplier refunded me but didn't want it back when it didn't fit, so if anyone can use it, it's yours for whatever the postage costs.
Thanks everyone for your input, especially @koalar
Just a bit more on this - the issue came back just after Christmas, but much worse - not just jerkiness when cold but stalling when coming to a stop, missing when running at speed or accelerating.
Was wondering what to do next, when I noticed that in the cold weather, the clock was resetting to 00:00 when starting the car first thing in the morning. That lead me think the battery might be on the way out, confirmed after a few searches on here showed that the reset clock is Fiat's helpful way of telling you to replace the battery. Battery tester also confirmed battery wasn't in great shape.
Long story short, stuck a new battery in it, runs like clockwork.
Was wondering what to do next, when I noticed that in the cold weather, the clock was resetting to 00:00 when starting the car first thing in the morning. That lead me think the battery might be on the way out, confirmed after a few searches on here showed that the reset clock is Fiat's helpful way of telling you to replace the battery. Battery tester also confirmed battery wasn't in great shape.
Long story short, stuck a new battery in it, runs like clockwork.
More modern vehicles, especially the latest ones with multiple computer modules, seem very critical of battery condition. I'm assuming these modules have "threshold" voltages and when the voltage drops below that they stop working properly? Of course, in a vehicle, drain on the electrical system varies depending on load so it's reasonable to assume that when the voltage approaches a critical threshold things will start to intermittently malfunction? Having grown up with electrical systems which had very little by way of electronics, it's taken me some time to factor this into my diagnostic regime. Long gone are the days when a vehicle with a poor battery will run satisfactorily as long as you can get it running and us oldies need to get our heads round this!
Clock resetting
Faulty battery
Faulty battery can cause the car to stall at junctions
Here's mine from 2017,
www.fiatforum.com
Faulty battery
Faulty battery can cause the car to stall at junctions
Here's mine from 2017,
1.1 cold start idle problem | FIAT Panda (Mk3)
Girlfriends active has started to play up. Its difficult to start. If you take your foot off the throttle it stalls. If you hold the throttle down for a minute then it will drive fine. Multiecuscan says the desired idle is 1400 RPM but it starts at 750 RPM and lowers to 700 and stops...
www.fiatforum.com
So, the problem is back, and with a vengeance. The new battery was only a temporary fix.
My missus drove to Reading yesterday in very wet conditions, roughly 1hr15 each way. Car was fine on the way there. She parked up for about three hours and then came home and the car was terrible - jerky, hesitant, missing, stalling (including when part way round a roundabout). Not sure if the fact it was wet is related.
She was considering parking up and calling for recovery it was so bad, but in the end made it home, but was too worried about the problem to risk going on the A3 and came cross-country instead. EDIT: Forgot to say I took the car out within 30 mins of her return and it drove fine. Most confusing.
I've ordered a CReader 3001 code reader so hope that might give some pointers if any codes are stored.
I'm thinking the issue is electrical or intake related as my prior fiddling in those areas (cleaning the MAP, changing the battery) have yielded positive, if temporary, results, so these are my current thoughts:
I've seen that there's an injector wire issue that can be solved temporarily at least by wiggling the ECU plugs/wires - but think this is only on the 1.1 and ours is a 1.2 Dynamic. But will pull and reseat the ECU plugs in case.
Failing alternator? Leading to low battery and recurrence of problem that new battery seemed to fix? How can I check this?
Cam or crank sensor issue? Not sure how to test them though.
MAP oiling up again - will pull it and clean it. Not sure how to test its functionality though.
Poor grounding? Would this be made worse by wet weather? Not sure where they are but worth pulling them and cleaning the ground wires and the body connection points to make sure they are grounding correctly?
Any thoughts on the above would be most welcome! Or any other areas to investigate?
TIA
My missus drove to Reading yesterday in very wet conditions, roughly 1hr15 each way. Car was fine on the way there. She parked up for about three hours and then came home and the car was terrible - jerky, hesitant, missing, stalling (including when part way round a roundabout). Not sure if the fact it was wet is related.
She was considering parking up and calling for recovery it was so bad, but in the end made it home, but was too worried about the problem to risk going on the A3 and came cross-country instead. EDIT: Forgot to say I took the car out within 30 mins of her return and it drove fine. Most confusing.
I've ordered a CReader 3001 code reader so hope that might give some pointers if any codes are stored.
I'm thinking the issue is electrical or intake related as my prior fiddling in those areas (cleaning the MAP, changing the battery) have yielded positive, if temporary, results, so these are my current thoughts:
I've seen that there's an injector wire issue that can be solved temporarily at least by wiggling the ECU plugs/wires - but think this is only on the 1.1 and ours is a 1.2 Dynamic. But will pull and reseat the ECU plugs in case.
Failing alternator? Leading to low battery and recurrence of problem that new battery seemed to fix? How can I check this?
Cam or crank sensor issue? Not sure how to test them though.
MAP oiling up again - will pull it and clean it. Not sure how to test its functionality though.
Poor grounding? Would this be made worse by wet weather? Not sure where they are but worth pulling them and cleaning the ground wires and the body connection points to make sure they are grounding correctly?
Any thoughts on the above would be most welcome! Or any other areas to investigate?
TIA
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Has the stalling at junctions come back
Has the clocks resetting come back
I see the MAP sensor covered in oil again, this will cause hesitation on acceleration
Pull the breather from the valve cover off and drive the car for a bit see if the symptoms go away
Jerky on very light throttle is often the accelerator pedal on cars with flyby wire throttles but I see yours is a cable throttle
The CReader 3001 is a good choice for the money as it does data logging, you will be able to graph the output of the throttle body
You will be able to log the inlet temperature and pressure, it normally the temperature that's wrong
Got to be a clue here, don't know what though
What are the plugs like, wet with fuel, wet with oil, black with carbon, fine,
Post a picture in the order they come out
Has the clocks resetting come back
I see the MAP sensor covered in oil again, this will cause hesitation on acceleration
Pull the breather from the valve cover off and drive the car for a bit see if the symptoms go away
Jerky on very light throttle is often the accelerator pedal on cars with flyby wire throttles but I see yours is a cable throttle
The CReader 3001 is a good choice for the money as it does data logging, you will be able to graph the output of the throttle body
You will be able to log the inlet temperature and pressure, it normally the temperature that's wrong
Got to be a clue here, don't know what though
What are the plugs like, wet with fuel, wet with oil, black with carbon, fine,
Post a picture in the order they come out
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OK, first things I've checked:
Battery/alternator - battery shows 12.6v with engine off, 14.02 with engine running but no lights or AC and 13.9 with lights and AC. On switching off, battery shows 13.1V dropping slowly down over time, so I think this shows alternator and battery are good.
Pulled the MAP sensor and it's oily.
Will try car with breather pipe detached next, and pull the plugs and take pics.
Edit - clock not resetting. But stalling at junctions was back yesterday.
Battery/alternator - battery shows 12.6v with engine off, 14.02 with engine running but no lights or AC and 13.9 with lights and AC. On switching off, battery shows 13.1V dropping slowly down over time, so I think this shows alternator and battery are good.
Pulled the MAP sensor and it's oily.
Will try car with breather pipe detached next, and pull the plugs and take pics.
Edit - clock not resetting. But stalling at junctions was back yesterday.
Withe a multi meter measure across the battery terminals
engine off, after it stood for an hour or so
At idle no electrical load
At idle withe the blowers on full, rear heated window and main beam on
Raise the revs to approx 3k
You beat me to it
If you raise the revs at this point the voltage should go back to 14V if it does the alternator is almost certainly fine
With the multimeter on volts one lead on the battery negative, one on the engine block
Crank the car, if you have a good ground the reading should be just under 0.2V
Crank the car, if you have a good ground the reading should be just under 0.2V
You've tried so many things already but I'll try to help.
The Launch is a very big and trusted name but there have been many posts on our forum about how our cars don't really "like" generic code readers and how they often lead you down a "rabbit hole" by throwing up erroneous results. I find Multiecuscan works well but there are one or two others which also get recommendations on the forum - Alfaobd being one? - Maybe others could make recommendations?
A simple way to check if the alternator is charging the battery would be with a voltmeter. Let the car stand for about an hour so the battery can stabilize then apply the meter to the battery terminals. You should see around 12.5 volts. A good battery may show a little more, ie 12.8, a poor one a little less, ie 12 .3. However if it's in this range it's likely Ok. now start the engine and run it at a fast idle - 1500 to 2000 rpm. Actually most alternators will charge strongly even at idling but running the engine just a little faster will ensure a good output. The Voltmeter should now be showing somewhere between 13.5 to 14.5 volts. If it does then it's probably charging just fine.
As you say, there is a known loom fault with the 1.1 but not, as far as I know, with the 1.2 But I like your idea to reseat the plugs. I apply a light coat of Contralube to any electrical connector before I reassemble it https://www.autoelectricsupplies.co.uk/p/contralube-770-the-terminal-connector It waterproofs, protects and improves electrical pathways.
Cam or crank sensors should leave a trouble code you can look for but sometimes they don't. "Misbehaving" when they get hot but working normally when started from cold is not unknown. Sometimes you can make them "misbehave" by lightly tapping them with the engine running. But do be very careful you don't get anything tied up in rotating parts!
Here's a pretty good video about checking MAP sensors:
One of the advantages of buying into Multiecuscan is it lets you watch stuff like this live on the screen but the video also shows you how to do it using just a voltmeter (multimeter)
Poor ground? The earth lead under the battery tray is always worth checking as they are known to corrode and fail. The exposed woven type is easy to check but the type with an insulating outer covering can, I'm told, corrode internally where you can't see it. I imagine a good "wiggle" will find it? I've only ever had the woven one on any of our Pandas.
