Technical LUMPY IDLE Panda 1.2 2004

[mikehopper]

Hi guys I've got a panda 2004 1.2 petrol. It's pretty lumpy on idle and can here a missfire ar tailpipe .. it does not idle smooth but as soon as you rev it it seems to even out. Drives normally except when you rev it or put engine underload it sounds like there's a metal tapping knocking coming from the engine...

So far I've checked timing all good
Fitted new plugs, coil packs leads

Injectors, if I remove Injector 1 or 2 it bogs down for a second then back to lumpy.. remove 3 of 4 Injector and it runs worse as in barely runs.

All 4 plugs were looking good( no heavy carbon or wetness) but changed them anyway.

Mes comes up with no other fault other than lambda after cat...
Could that be the cause?

Any ideas?

 

[koalar]

pull a spark plug lead off the coil pack
start the car
make a note what the difference in running is

do the same one at a time for the other plug leads one jar a time

don't leave the car running too long with a lead disconnected a minute is fine

my guess one or more cylinders will make little difference these are the ones not firing properly

report back it will give us somewhere to. start

 

[The Panda Nut]

I would also remove and clean the throttle body and while its off check that the manifold isn't swimming in mayo. I have fitted catch cans in the breather line (c £15 off ebay) and find this has helped stop mayo building up in the manifold and gumming up the maf sensor. Occasional cleaning is still required but the difference in smoothe running, and power is substantial. on 2007 cars the maf may be elsewhere and cleaning may not be as straight forward as on my 2011 beast but a dirty maf does have a profound effect.

 

[mikehopper]

pull a spark plug lead off the coil pack
start the car
make a note what the difference in running is

do the same one at a time for the other plug leads one jar a time

don't leave the car running too long with a lead disconnected a minute is fine

my guess one or more cylinders will make little difference these are the ones not firing properly

report back it will give us somewhere to. start

Removing the leads from 1 and 2 make little difference, the car compensates without them
. Removing 3 and 4( each 1 at a time) the car struggles to run...
Both 1 and 2 removed and it still runs but very lumpy.

No noticeable difference between 1 or 2 unplugged

 

[mikehopper]

No gunk in throttle body

 

[redandwhite]

Have you tried an Italian tune up?

 

[koalar]

Removing the leads from 1 and 2 make little difference, the car compensates without them
. Removing 3 and 4( each 1 at a time) the car struggles to run...
Both 1 and 2 removed and it still runs but very lumpy.

No noticeable difference between 1 or 2 unplugged

dam

i would suspect there was a break in the cylinder head gasket between cyl 1 and cyl 2

before spending loads of time it would be a Good idea to do a compression test

lets see if I can find any other checks worth doing

but the symptom of less noticeable at higher revs would also fit

I will not call it yet. Give me half an hour to see if there is a direction to go

 

[mikehopper]

I've done a fair few cylinder head gaskets so it doesn't faze me... if it is just that I'd be happy...

Would that also give me a metallic knock on load acceleration/ or sudden rev from idle

 

[koalar]

I've done a fair few cylinder head gaskets so it doesn't faze me... if it is just that I'd be happy...

Would that also give me a metallic knock on load acceleration/ or sudden rev from idle

here the symptoms when its really bad, depending how big the beak is you will get some are all

driving symptoms

Knocking noise when accelerating cold engine, clear up when hot

poor power at lower revs, bogs down then picks up, clears up when hot

stalls at junctions

erratic idle, revs rising and falling, sometimes a bit shaky at idle

judder on pulling off

misfire can be heard from the exhaust

poor fuel economy

occasionally need the coolant top up and occasionally a gurgling noise after you switch the engine off

 

[mikehopper]

here the symptoms when its really bad, depending how big the beak is you will get some are all

driving symptoms

Knocking noise when accelerating cold engine, clear up when hot

poor power at lower revs, bogs down then picks up, clears up when hot

stalls at junctions

erratic idle, revs rising and falling, sometimes a bit shaky at idle

judder on pulling off

misfire can be heard from the exhaust

poor fuel economy

occasionally need the coolant top up and occasionally a gurgling noise after you switch the engine off

OK, so no coolant loss.

Yes knocks occasionally when cold

Erattic idle, no stalling

Yes can hear misfire at exhaust

 

[koalar]

I would do a compression test

Garage would do one for you

I bought on recently for around £10 on offer on Amizon. Not great but does the job

 

[koalar]

It’s one of those. You can spend a lot of time trying to eliminate everything else. Or do a quick test for what’s likely. And if it’s not move on.

Unfortunately most people don’t own a compression tester in there tool box.

 

[mikehopper]

It’s one of those. You can spend a lot of time trying to eliminate everything else. Or do a quick test for what’s likely. And if it’s not move on.

Unfortunately most people don’t own a compression tester in there tool box.

Just ordered a kit off Amazon. Eta tomorrow

 

[koalar]

I think it’s a wise move

Most garages will charge more than its cost

At the end of the day it can save so much time going round in circles.

Once bought you have it for future use and help friends.


The rubber cone adapter is fine for this. As long as someone is there to turn the key. You do have to push down hard. Can’t remember what my good cylinders were around 220 PSI I think

 

[mikehopper]

I think it’s a wise move

Most garages will charge more than its cost

At the end of the day it can save so much time going round in circles.

Once bought you have it for future use and help friends.


The rubber cone adapter is fine for this. As long as someone is there to turn the key. You do have to push down hard. Can’t remember what my good cylinders were around 220 PSI I think

I'll use the screw in type. Should be better result than push in bit.. if its not level or seated correctly could get a false reading.

I'll post back tomoz with test results

 

[mikehopper]

Bingo.

Head gasket gone between cylinder 1 and 2.

I pre empted the issue and bought all the parts this morning..

40 mins for head off not too bad..

 

[koalar]

ditto

Running bad, cylinder head | FIAT Panda (Mk3)

Right let's start with the driving symptoms Knocking noise when accelerating cold engine, clear up when hot poor power at lower revs, bogs down then picks up, clears up when hot stalls at junctions erratic idle, revs rising and falling, sometimes a bit shaky at idle judder on pulling off...

www.fiatforum.com

be carful ordering parts,

head gasket kits, there's more than one, euro 4 and euro 5 are different but most eBay list the same up to 2012
head bolts are all the same

 

[mikehopper]

I've bought from the supplier before...

It's now all back together and running sweet as a nut...
No splutter, no tapping..
Spot on..



Only other issue is an abs light on, says rear RH sensor but there is no abs, so I'm assuming it's a different ecu with higher spec..
I know punto 1.2 1999 to 2006 you can tell the ecu it's none abs but there is not a function for it on the Pandas.. ( using MES and in proxy alignment , you can set abs, gearbox type etc)

 

[DaveMcT]

Probably not an issue this time, but idle speed that doesn't settle quickly or runs at higher revs yet stalls easily can be an air leak after the throttle body. The O2 sensors and ECU often hide the symptoms but it's easy to test with a spray of easy start around the inlet side of the engine.

 

[koalar]

I've bought from the supplier before...

It's now all back together and running sweet as a nut...
No splutter, no tapping..
Spot on..



Only other issue is an abs light on, says rear RH sensor but there is no abs, so I'm assuming it's a different ecu with higher spec..
I know punto 1.2 1999 to 2006 you can tell the ecu it's none abs but there is not a function for it on the Pandas.. ( using MES and in proxy alignment , you can set abs, gearbox type etc)

Well done on sorting it


Strange there’s no ABS on a 1.2 ? I was under the impression only early 1.1 active were the only ones that didn’t have ABS?


A lot of the functions in multiECUscan are missing for the Pandas and what is available is often also year dependant Such as swapping the fog lights over is on the post 2012 but not earlier years. It’s a shame it is what it is. I miss short and long fuel trims.