Technical Odd twinair question

[varesecrazy]

Hi all,

Brought about by recent events.. a question

Your Digital Temp display..

Does it show COLD ..or tend to stick at '1 block' ?

Backstory.. car seem to display '1 block' most of the time.. and if started in that state it will run poorly Pretty much 100% reliably

This week on a @20'c evening I set off 1 block showing dugger dugger lumpy running

4 minute trip

Sat for 10 minutes

Restarted the motor..selected reverse and got a Chime from the dashboard
Message scrolled 'Liquid Temperature'..or similar

Car drove perfectly back '2 blocks showing'

Coolant level still perfect.. driven 15 miles today..all good


'Poor Running' :
Anybody remember the old twinchoke Webers used to 'vapour lock' stuck in traffic and motors ran rough 'fuel evaporation'

Thats basically how it feels its done it from purchase at 9k..now on 35k

Runs fine Hot..or Cold

Ok through a warming cycle

BUT STARTING ON 1 BLOCK is almost guaranteed to run sick for 1 minute.. then fine as it warms

Will get the error code in coming days

In the meantime
I might build a POLL for temp gauge readings

Thanks for looking

 

[varesecrazy]

Nobody will be shocked to read that there were NO ERRORS STORED..

Here are a couple of the relevant pics though

As you can see outside air 20 everything under the bonnet @35

Been parked for 3 hours after the commute.. so all 'normal' to me

 

[Panda IIs]

Your Digital Temp display..

Does it show COLD ..or tend to stick at '1 block' ?

So, my TA 4x4 2013 84k miles runs up to 3 blocks pretty quickly and sits there - no lumpy running as you describe. Even with short trips and stops.

It's not entirely clear to me whether you are saying it never gets above 1 block? If that is so then I'd suggest the thermostat is not functioning?

The symptoms you describe do, however chime with me (no pun intended) but with a VW Golf 4 which would run lumpy after a short run and have a very stinky exhaust (running rich). I resolved the issue by changing out one of the coolant sensors (the Golf appears to have a couple one of which just feeds the ECU). My analysis of what was going on was that the ECU was getting a dodgy temperature signal at low(er) coolant temperatures and was fuelling for a cold start. Maybe something similar is going on? Can you look at fuel trims (live data) with multiecuscan? Perhaps this would give some insight?

Incidentally the FIAT has just been started for the first time for 4 weeks or so. It did start on one cylinder with its companion picking up after 10 seconds or so. This I think was oil draining from the UniAir actuators. It's been fine subsequently.

 

[varesecrazy]

Thanks for that @Panda IIs

The temperature reads 'normally'

Blank when COLD and gets to midway pretty quickly
( my euro5 ta in a punto does NONE of this.. but has a needle display..so I cant make a direct comparison..)

It warms just like my other TA


AS i said it drives just like those old Weber carbs

From Cold start and Runs strongly

From Hot starts and runs strongly

But if display shows 1 block of Temp when starting it'll run poorly fo around a minute.. then fine

Had it checked over at supplying Fiat Alfa specialist..no fault found

Its covered another 10k + still the same

Ive changed plugs.. but wasnt anticipating any change

Convinced its purely fuelling.. :-(

Conversely.. my euro 5 can stumble if I half.stall it , this euro 6 never has

Im kind of living with it.. but had considered swapping sensorts between the 2 x twinairs



Experience tells me they will then BOTH run differently.. and I will be none the wiser..

 

[varesecrazy]

I have never tried 'live data'

Maybe a comparison between the 2 x cars would highlight a major difference

 

[The Panda Nut]

Surely if the air temp and the engine temp are so similar the thermostat has gone? I would change that and the temp sensor to start with.

My two TA's current and previous have both been the same and start on no bars move to 4 in about 3 miles on a cold day. In really hot weather last year they started on 1 bar.

The only rough running has been after lack of use in the pandemic and I think was oil pressure building back up.

Sometime the noise are most peculiar. I have decided if it doesnt sound immediately expensive I will ignore it and the oddness seems to disappear.....

 

[varesecrazy]

Surely if the air temp and the engine temp are so similar the thermostat has gone? I would change that and the temp sensor to start with.

Its all in one warm box.. (engine stopped for 3 hours)

Under the bonnet

My two TA's current and previous have both been the same and start on no bars move to 4 in about 3 miles on a cold day. In really hot weather last year they started on 1

Thats pretty much how this Panda is

I am driving the Euro 5 today..

Will make some comparisons

 

[Panda IIs]

I have never tried 'live data'

Maybe a comparison between the 2 x cars would highlight a major difference

I don't know that MES has live data (I don't have access) but I use another ODBII on the mentioned VW and others and find it more useful than simply having codes reported that are just generic.

 

[The Panda Nut]

Mes allows you to graph many sensor outputs while you drive or just run the engine. It does help build a better picture of what is going on. You can monitor engine temperature so while I have not tried I think you could watch warm up and thermostat and fan operation and effectiveness..

 

[varesecrazy]

I am driving the Euro 5 today..

Will make some comparisons

Pics for comparison:

All temps are higher.. but Needle of Gauge shows 'zero' ( a warmer evening.. parked for 4 hours)

 

[varesecrazy]

I had a quick look at 'Graph' on the MES

Not really sure where to start..