Hi guys, Hope you can help me.

I have recently bought a Fiat Brava SX80, 1242cc on a 51 plate (late 2001) 53000 on the clock.

The problem is that as I pull up at lights or a junction the engine stalls. (orange engine management light is on permanently)

Otherwise, it runs perfectly. If it`s possible, a blip on the throttle as soon as the clutch is depressed stops it stalling, but that can be difficult sometimes in traffic.

Reading other threads on this wonderful forum gave me some ideas, but I don`t really understand these modern vehicle electronics.

Things I`ve tried:

Removed and cleaned crank sensor. - no effect

checked for obvious signs of air leaks - none found

General check of wiring and connectors for corrosion - nothing found

Reset EMU by disconnecting battery neg for 1hour reconnecting and leaving on tick over for 5mins then restarting and driving normally. - Light went out and stayed off for about 16miles before problem re-occurred and stalling returned.

Took car for diagnosis at local garage (they said they could do this OK) that showed that the MAP sensor was faulty so had it replaced (cost of everything £102.25) - was OK for about 5 miles then problem re-occurred.(the garage said the map sensor was the only fault shown so can`t understand why it didn`t work)

After reading more posts here, it seems that by resetting the EMU I now need to have the throttle position sensor reset by a main dealer,(tick over is 800 rpm) but was wondering if you could help narrow down the problem or give a better idea of what might actually fix it. I can`t afford to keep replacing bits in the hope that that cures it.

Any help would be very much appreciated

Regards

shunter2150 said:

After reading more posts here, it seems that by resetting the EMU I now need to have the throttle position sensor reset by a main dealer,(tick over is 800 rpm)

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if after the reset your idle sticks at 1500rpm or is erratic then you need a TPS relearn. you are fine if the idle is at 800rpm, it means the ecu did not lose the TPS range during the reset. if the idle was not correct then i would think the stalling problem was the TPS (or coolant temp sensor), but not in your case.

check that the hose for the MAP is not leaking or blocked.

lambda sensor faults do not show up on a diagnsotic, and they are well known to cause stalling at idle, however the clue to a lambda fault is if the stalling only occurs after the engine has warmed up. if the engine never stalls in the first few minutes of driving that would be a good clue that the lambda is to blame.

a diagnostic at a fiat dealer is often better becuase they have the correct equipment. unfortunately that costs about £65 usually even if they find no faults.

Thanks jug,

On this engine there seems to be 2 lambda sensors, (upstream & downstream) can you suggest which one to replace first or should it be both?

I`m guessing it will be cheaper to replace one than go to a fiat dealer for a diag that finds no faults (possibly)

I`ve attached a pic of the 2 lambda locations

Thanks again.

the diagnostic sensor (the most rear fitted sensor) can not cause any problem other than illuminating the engine management light so you can be fairly sure that is not your problem.

the regulating sensor (fitted first in the exhaust) is the one that has a big impact on fueling. that is the one that would be likely to cause problems if it failed.

scrapyard sensors are the cheapest way to go about this, fitting a new sensor cant do any harm, but it costs more.

try disconnecting the regulating lambda sensor to see if it has any effect.

jug said:

scrapyard sensors are the cheapest way to go about this, fitting a new sensor cant do any harm, but it costs more.

try disconnecting the regulating lambda sensor to see if it has any effect.

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Thanks jug, I`ve found one for £10 + postage. Brilliant.

I guess its the top one, No13 in the pic, that probably needs replacing. Would you be kind enough to confirm thats the one you meant.

Thanks a lot for your help.

Had the same problem several weeks ago with our 1.2 80 sx, see Brava running problem pg4.
Mates garage said it was the MAP/MAF sensor.
Forum member Jug pointed out where to find it (number 8 on your pic) and on inspection it was covered in oil, cleaned it and all was ok but only for a few days.
Took it to Fiat dealership who diagnosed throttle sensors and needed a complete new throttle body, cost - several hundred ££'s!!!
No way could we afford that??
Decided to clean throttle body just in case it too was dirty.
Half a can of carburetor cleaner and guess what??
Working PERFECT, light has gone off and runs better than before!!!!
Just removed the intake pipe, gently opened the throttle butterfly with my thumb and gave it several long blasts of cleaner.
Also i placed a lint free cloth slightly inside the throttle and hanging out of it to mop up all the dirty solution.
Good luck!

Dave.

shunter2150 said:

I guess its the top one, No13 in the pic, that probably needs replacing.

Click to expand...

correct.

Thank you, thank you, thank you

Just to let you know that my problem is now sorted.

Thanks to everybody for your help.

davevandamm, I did exactly as you described, that stopped the engine stalling and turned off the ECU light.

When I looked inside the throttle body it was coated in a black tar like substance, so much that the butterfly couldn`t close properly.The carb cleaner dissolved it in seconds.

BTW jug, I eliminated the lambda sensor by following your instructions, that saved me a few bob.

Thanks again,

do you guys have induction kits that you use filter oil on?

I think the K+N panel filter played a hand in our problem.
Was very dissapointed in Fiat dealerships £38 diagnostics test.
Ok it pointed out the throttle body, but i did tell them about oily K+N.
They would rather just charge a fortune and fit a new throttle body rather than attempt to clean it.
Anyone can slap on a throttle or clean one for that matter!!
Strange how there are no parts that can be replaced, it has to be the whole unit???
I've been told that some throttles, Ford? have a coating inside to prevent oxidization and carb cleaner can damage it. Hope it has no affect on Fiats!

Sorry for delay, been away.

As far as I know, my engine is factory standard with no mods.

Showing my ignorance, I don`t know what a K&N panel filter is, sorry. Just happy its cured, thanks to you guys.