Technical Engine light on - diagnostic showed a misfire
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Technical Engine light on - diagnostic showed a misfire
Hello,
I have the same problem with my TIPO 1.4 16V 95CV with 70 000 km. Do u remember which one sensor was faulty?
Lambda failure is only a result of running too long with poor spark plugs. It looks like that the dealer doesn't automatically change the spark plugs each 18600 miles (30 000km). It takes a little more miles to get a misfire, but why even wait for the fault code to show up. It has already damaged the cat and the lambdas by then. The wrong fix is to ignore the plugs and clear the code and just keep driving. 
Lambda failure is only a result of running too long with poor spark plugs. It looks like that the dealer doesn't automatically change the spark plugs each 18600 miles (30 000km). It takes a little more miles to get a misfire, but why even wait for the fault code to show up. It has already damaged the cat and the lambdas by then. The wrong fix is to ignore the plugs and clear the code and just keep driving.
I changed plugs at 30kkm and 60kkm, when this error displayed for a first time I had 70kkm and the first thing what i did was new plugs...
Redzio, you could go ahead and google what things cause misfiring and start from the cheapest. Like a leak in the pcv breather hoses or blockage. Very easy and cheap to replace.
Does it show lambda and catalyst test failed in the monitors? Probably still fine when u find the cause.
Does it show lambda and catalyst test failed in the monitors? Probably still fine when u find the cause.
155Ringman
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Other than replacing the lambdas, has anyone actually got a definitive cause for this? I have 2 Tipo's, both 1.4Tjet Estates, both with EML's on with the same fault. I have replaced the spark plugs and a degraded breather hose that leads to the inlet as it may have leaned out the mixture. Every time, the EML comes back on on the first drive afterwards with the same codes relating to the Lambda's. I've looked at some live data while driving and there's not a lot of drift in the signal so I'm reluctant to change the sensors out if they are just indicating an issue elsewhere.
I replaced both lambdas, ignition coils, put on new spark plugs, replaced the mapsensor and cleaned the throttle body. Unfortunately, the error still pops up ... I looked with the inspection camera inside the catalyst and it seems to me that it is clean. Unfortunately, everything indicates that it is a catalyst.
I plan to replace the crankcase breather hose.
155Ringman
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I replaced the breather hose that passes through the engine cover and heads down to the crankcase as they were badly deteriorated / cracked and leaking, but that didn't solve it either unfortunately. I've got an MOT coming up in around a month so I'm going to have to spend a bit more time trying to resolve it as any EML is an instant fail now.
Why change the map sensor? Did you buy genuine Bosch sensor? Are Lambdas Bosch too? Other brands don't work so well.
Probably nothing wrong with the sensors. Hard to tell you could list all the current codes.
Also keep in mind that after changing the sensors, you also need to reset all the trouble codes.
It's quite a new car still. Shouldn't you be taking it to a Fiat garage? It may be an intake manifold leak if there's a fault code for MAP sensor.
Probably nothing wrong with the sensors. Hard to tell you could list all the current codes.
Also keep in mind that after changing the sensors, you also need to reset all the trouble codes.
It's quite a new car still. Shouldn't you be taking it to a Fiat garage? It may be an intake manifold leak if there's a fault code for MAP sensor.
The tipo has be out since 2016 I'd say most of the cars made are now out of warranty
I tried to clear the P0420 error. No other errors. All the things I replaced came from a friend's Tipo which don't have any errors and all was original parts. After replaced i reset the trouble code.
What date of production are your tipo's? I heard that the end of 2017 and the beginning of 2018 had some faulty catalysts... my is 12.2017.. so mby that is true.
It's still pretty recent model and you should take the car to a Fiat service center to get it fixed. The catalyst probably failed too early and Fiat could make you a good offer. They do have some goodwill policies even for cars out of warranty. It does not come easy though. You might be able to find a good replacement catalyst and it replaced a lot cheaper though.
Does the monitors show catalyst check failed? Then it is possible that it failed.
Does the monitors show catalyst check failed? Then it is possible that it failed.
155Ringman
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They are registered 2017 & 2018 but not sure of date of production. I'll check it again at the weekend and see what codes I have now. I think my code was the pre cat lambda iirc so if that is the case, it shouldn't be the cat hopefully. I don't do service centers, always do everything myself wherever possible.
155Ringman
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Update, checked the codes again and was getting pre cat Lambda errors, bought both and fitted along with an oil/air filter service. Found that the last service done by a main fiat dealer had not changed the oil filter, only the oil. This is why I do all my own servicing. Anyway, lambda's changed, codes cleared, MOT passed and has been fine for around a week now with no further codes. I've put the 'good' post cat lambda off to one side to fit to my other tipo and see if that works without having to buy another 2 sensors.
