Panda (Classic) New member Engine cut out at speed

[little miss milly]

Hi Fiat Forum,
I'm a new member and have no experience of forums so here goes...
Have run classic pandas for 20 years. Current car is made up from an 1100 Selecta 1994 which I converted to manual gearbox using a 750 4 speed box.
Good round town with lower gearing and surprises many as I put 750 badge on boot! It has single point injection + 2 coil packs/no distributor.
Got a little problem though- At speed on motorway, say 60mph, when throttle is lifted off when going down hill, after a few seconds engine cuts out completely. Pushing the throttle has no effect for about 5-10 seconds when suddenly engine leaps into life and continues normally until next lift off.
Also (!) intermittent red injection light comes on for a bit during normal driving - at speed or whilst idling giving lumpy idling.
Plugs were sooty so thought about ignition fault so changed plugs, leads and Lambda sensor (also sooty).
My next plan is to change engine temp sensor in case ECU is thinking engine cold & making mixture rich..

Words of wisdom appreciated and hello to members

Little Miss Milly (my wife's name for the Panda)

 

[kolza]

Welcome to the forum.

Regards the issue - i would check the stepper motor.

What is the engine code? sounds like P55 engine.

 

[little miss milly]

Welcome to the forum.

Regards the issue - i would check the stepper motor.

What is the engine code? sounds like P55 engine.

Thank you for quick response & hello. Regret I don't know where to find engine code.
Stepper motor- I understand stepper motor powers butterfly position to provide correct idling speed? My idling speed is fine.. What do you think?

thanks and I hope I drive the forum thread correctly, apologies if not...

 

[Didge3]

Sounds odd. When this happens I assume the clutch is disengaged so the car is rolling along and the engine is returning to idle but instead it dies?

 

[kolza]

Also (!) intermittent red injection light comes on for a bit during normal driving - at speed or whilst idling giving lumpy idling.

Engine code is stamped or dot printed on the top of water pump housing.

 

[firstcar-Y10]

My stab would be throttle position sensor, fuel cut off would be right if the car is running with a completely closed throttle in gear, but it sounds like there's a delay picking up when you open the throttle again. Other alternative would be the ecu is looking for some info from that Selecta box that you don't have fitted any more maybe but I'm really not clued up on Selecta electronics, anyone?

Oh and hello!

 

[panda1408]

Welcome to the Forum,

Rather than guess and change parts I would see if you can get a diagnostics machine plugged in, that might give you some clues as to what is wrong and will enable you to see if the various sensors are giving correct readings. A garage should be able to do this for you, or if you have a laptop then you can buy the required cable for around £20 and the software you need is free.

Alternatively, they may be a forum member nearby who already has the kit that could help you out

 

[little miss milly]

Happens when clutch is engaged and throttle pedal released- thanks

 

[little miss milly]

My stab would be throttle position sensor, fuel cut off would be right if the car is running with a completely closed throttle in gear, but it sounds like there's a delay picking up when you open the throttle again. Other alternative would be the ecu is looking for some info from that Selecta box that you don't have fitted any more maybe but I'm really not clued up on Selecta electronics, anyone?

Oh and hello!

Thank you- it was fully OK for 4 years so guess it's not selecta ECU?

 

[little miss milly]

Welcome to the Forum,

Rather than guess and change parts I would see if you can get a diagnostics machine plugged in, that might give you some clues as to what is wrong and will enable you to see if the various sensors are giving correct readings. A garage should be able to do this for you, or if you have a laptop then you can buy the required cable for around £20 and the software you need is free.

Alternatively, they may be a forum member nearby who already has the kit that could help you out[/QUOTE

Excellent advice- I didn't know free software was available for my laptop.
What cable do I search for? I'm at Woking Surrey if anyone has gear.

Thanks for info

 

[Didge3]

Happens when clutch is engaged and throttle pedal released- thanks

The clutch is engaged? Surely with the clutch engaged in a gear the momentum of the car moving at 60mph keeps the engine from stalling?

 

[panda1408]

No problem, I would offer to help but I'm little bit too far away I think!

This is the cable:

http://www.scantool-direct.co.uk/fiat--alfa-romeo-multiecuscan-kkl-cable-and-3-pin-connector-31-p.html

And this is the software:

http://iaw-scan2.sourceforge.net/

Can be a little tricky to get it set up with the drivers etc but is very useful once working.

 

[little miss milly]

The clutch is engaged? Surely with the clutch engaged in a gear the momentum of the car moving at 60mph keeps the engine from stalling?

It's like switching off ignition as engine ceases firing completely. Speed then drops as max engine braking occurs until engine starts firing normally again and then power returns with a jolt as my foot is then on throttle willing the engine to get going again! Thanks for your help.

 

[little miss milly]

Thanks for diagnostics info- very helpful.

 

[Didge3]

It's like switching off ignition as engine ceases firing completely. Speed then drops as max engine braking occurs until engine starts firing normally again and then power returns with a jolt as my foot is then on throttle willing the engine to get going again! Thanks for your help.

That is certainly strange, has it always been a problem or somethings that has developed more recently? As I'd be tempted to say its something to do with the car previously being a Selecta if its been a problem since the conversion?

If so I'd imagine the ECU can see the throttle has closed but doesn't know what the transmission is doing whereas the Selecta box probably has sensors that the ECU picks up on and maybe for some reason that is causing the engine to stop firing? Only a guess, does the engine have the same ECU it had when it was a Selecta or was that changed to one from a manual car?

 

[Dragon Man]

the sensors i would check would be the crank position sensor, the throttle position sensor and the manifold absolute pressure sensor.

also a diagnostics would be a good thing to do

the sensors should all be the same as the Cinquecento Sporting and Punto 55 mk1. (anything with the 1108cc FIRE engine)

 

[little miss milly]

That is certainly strange, has it always been a problem or somethings that has developed more recently? As I'd be tempted to say its something to do with the car previously being a Selecta if its been a problem since the conversion?

If so I'd imagine the ECU can see the throttle has closed but doesn't know what the transmission is doing whereas the Selecta box probably has sensors that the ECU picks up on and maybe for some reason that is causing the engine to stop firing? Only a guess, does the engine have the same ECU it had when it was a Selecta or was that changed to one from a manual car?

No problems at all for 4 years after conversion, then one day it happened.

thank you for your info.

 

[little miss milly]

No problem, I would offer to help but I'm little bit too far away I think!

This is the cable:

http://www.scantool-direct.co.uk/fiat--alfa-romeo-multiecuscan-kkl-cable-and-3-pin-connector-31-p.html

And this is the software:

http://iaw-scan2.sourceforge.net/

Can be a little tricky to get it set up with the drivers etc but is very useful once working.

Thank you for your help. Got the software running and it indicated lambda sensor, which I had replaced. Bought another and bingo, all fixed!! Didn't help having the cam belt out by one tooth either. Now goes like a dingbat.
I need a 5 speed gearbox and front bumper moulding- any advice on sources?
thanks

Tony

 

[kolza]

I need a 5 speed gearbox and front bumper moulding- any advice on sources?
thanks

Tony

Please put wanted add for the parts required.

There are two types of gearboxes but as your panda have lambda i assume you need the cable driven one. There is one 5 gear cable drieven un the classified as well.

I can help you withthe front bumper, it would be spotless OE one. CAn get some photograps made if youre interested? Do you need the mounting brackets as well?

here is the g/box
https://www.fiatforum.com/classifieds/showproduct.php?product=33582

 

[little miss milly]

Thank you for your reply. Can you give me price for bumper?
ref gearbox- I have fitted a 4 speed 750cc gearbox with rod change to the 1100 engine in place of old selecta box which died. The top speed is a bit limited and it is worn so looking for 5 speed. can you tell me if I need to find a 5 speed rod change lever as well or will my 4 speed one fit a 5 speed box?
Many thanks
Tony