Bravo 1.4 12V
1998 S.
Hold your breath...162,000miles


Hi welcome to my first post, sorry it will probably be long.

Please can anyone make a suggestion as to the cause of last nights drama. We were at a local Retail Park, and as you would expect with the sales got stuck in traffic for a week or two ... The car was running absolutely fine through all the traffic and madness. Until near home, we stopped for my girlfriend to jump out and go to the shop. As we got out the Car sort of ... POPPED ! nothing loud or dramatic. Just a little POP (sounded like more from the engine than the exhaust). But then started to run rough and missfire.


I stayed in the car with the kids, and gave it a rev to try and clear it, but it just kept on missfiring and struggling to rev upto about 2500rpm. Turned it off and checked under the bonnet for any sign of loose wires or damage, but all was fine.


On trying to restart it when she came back, it again struggled and missfired but ran. But we could Smell a sort of acrid plastic smell coming from the exhaust and it did not like being put under strain when trying to pull away to get home. After about 30 yards I pulled over and checked it again under a street light but couldn't see any problems. Ended up driving it back in First, Second and at one point Third gear at low revs doing about 15mph with the hazards on. By the time we got back (about 3 miles) the car stank of burning plastic/chemicals ?!


No previous major problems, Oils fine, resonably new plugs (10 months ish), leads seem o.k. Only that the fuel consumption has started to increase over the last two weeks, but with the car running o.k I put it down to having the heater and lights on more, it being winter.


Spoke to a decent Exhaust place this morning for some advice, he reckons that the Cat has gone, possibly over fuelling. Said to take it down and they can take a look to find out for sure, but without finding and fixing the cause then it will happen to the new one the same. Looking through the forum it seems the concensus for this type of problem is the Coil Pack, but I can't see how a simple and reletively mild missfire could dump so much fuel in such a short space of time to cause the Cat to melt its self inside out.


In Summary ( finally ! )

Rough Misfiring Idle
Misfiring
Hesitation
Struggling under Strain
Kagarooing when driving under strain(More so in 3rd)
Backfiring , sounds like into Inlet manifold
Increased fuel consumption
ACRID SMELL !

Sorry for the essay, hope someone can help.
Thanks.

Oh - Just had its MOT on the 17/Dec/09 Passed and sailed through Emissions test

Is the managment light on?

Cheers

SPD

Hi,

Yes the Injector Light is on, but that flickers on and of to its hearts content as they all seem to. But it only came on a little while after the misfiring started. There are NO other lights, engine managment etc.

There really was no warning of a problem, other than the increased fuel consumption.

I'm just about to go and check the resistance figures on the Coil Pack now. Its sat on the drive so should only take 10 mins.

get the ecu read to see why its on

Managment/injection/ecu light on indicates that the management system can't cope with whats happening.

It is possible that a coil pack has gone down, this results in unburnt fuel heading down the exhaust to the cat.

The injector sqiurts a few thousand times a minute, doesn't take long to contaminate the cat.

Should 'clean up' once you get the car firing on all four.

Cheers

SPD

How did the coil test go? The ECU management light should never be on/flicker while your driving, the ECU is detecting a fault.

Welcome to the forum, 162,000 miles is impresive

Right, Sorry it took so long. But forgot that you have to remove the battery and its Bloody cold out there...

I checked:

Injector - 4.72 kOhm (Spec 3.3 - 1.5kOhm @ 15 - 30oc)
Coolant Temp Sensor - 5.78 kOhm (Spec 5,000Ohm @ 0 oc)
RPM/TDC Sensor - 661 Ohm (Spec 774 to 946 Ohm @ 20 oc)
Lambda Sensor - 4.5 Ohm (Spec 4.5 +- 0.5 Ohm @ 20 oc)
Coil Pack
- Primary A (Cyl 2 & 3) 1 Ohm (Spec 0.45 to 0.55 Ohm)
- Primary B (Cyl 1 & 4) 1 Ohm (Spec 0.45 to 0.55 Ohm)
- Secondary C (Cyl 1 & 4) 12.36 kOhm (Spec 12,000 to 14,600 Ohm @ 23 oc)
- Secondary D (Cyl 2 & 3) 12.53 kOhm (Spec 12,000 to 14,600 Ohm @ 23 oc)

So now I even more confused, I expected at least one of them to be out. even though there is a little variation, you have to take in to account that its about 2-3 oc outside at the moment and the car hasn't been ran today.

I did just try to sart it after doing the tests and it was as if it struggling to get the fuel through. I nearly got it to start 2 / 3 times. But it wouldn't bite. And there is still a strong smell coming from the exhaust, lingering from last night.

Any ideas?

Is primary A and B readings ok? they are both 0.45Ohm to high.

Have a look at this link, it fits all symptoms except backfire and CAT smell.
https://www.fiatforum.com/bravo-bra...v-throttle-potentiometer-position-sensor.html

when my puntos throttle position sensor ****ed, it used to die above about 2000 revs, misfire, pop etc so it could well be that!

I was really lucky Beau, found a brand new throttle body on a scrapped car. Got it for £10.

Adrian Bravo said:

I was really lucky Beau, found a brand new throttle body on a scrapped car. Got it for £10.

Click to expand...

i got mine from a scrap yard for £5 lol but it wasnt 'brand new'

has the timing belt jumped a tooth?

the fact you can smell stuff burning suggests to me it's something nasty gone on. if the timing jumped and it started chucking fuel into the cat, it'd get v hot - and explain burning smells.

sniff round the engine, try and locate where / why it smells burnt.

i suspect the ECU light flickering was just due to the car misfiring / knock sensor going loopy

id ignore the electronics and look at the mechanics of it. check your plugs, are they all the same colouring, any oil in the coolant, coolant in the oil?

arc said:

has the timing belt jumped a tooth?

the fact you can smell stuff burning suggests to me it's something nasty gone on. if the timing jumped and it started chucking fuel into the cat, it'd get v hot - and explain burning smells.

sniff round the engine, try and locate where / why it smells burnt.

i suspect the ECU light flickering was just due to the car misfiring / knock sensor going loopy

id ignore the electronics and look at the mechanics of it. check your plugs, are they all the same colouring, any oil in the coolant, coolant in the oil?

Click to expand...

Good call on the timing, well worth a look.

Cheers

SPD

162K on a 1.4! wow my 1.2 was on 135K.
Same engine all through at a guess, which means it will be breathing quite heafty by now, so have you checked the oil breather circuit it could have poped a hose off some where which now means the engine emissions circuit is breached so it may be sucking more air than needed , the acrid smell could be the fumes from the engine as it runs.
At around 130k I started to get throttle housing problems as in rough running so once a year I would spray it with carb cleaner to clear out oil residue from in side it, if I pulled the oil breather pipe off it it ran like an old pig missing, shaking flat off the throttle, what I am trying to say is it could well be age of engine, trying looking at air filter it may be contaminated with oil fumes, which is like a film, so it would start blocking your air filter = lower MPG - less air getting in through air filter, it could also be contaminating your carb, blocking jets, 162k on a small petrol engine is quite a run for it and it may be now looking to retire, or it could be as simple as a blocked breather pipe which has poped off, cat problems are usually like a sulpher smell but that could be a by product of the drive home at low speed with a dieing engine flooding it with fuel, the poping sound is the key? sounds to me like something has blocked, caused presure, poped off and now runs like a bag of crap, on your mileage I would check the emission system, and breathers. Incidentally with a breather hose off mine hated starting, some cars wont start with them off as they need a closed circuit to run, good luck! great mileage! keep it going. feed him nice oil! not cheap crap and he wil love you for it