Problems with the exhaust temperature sensor.

[Juggler]

I have a 2015 Autotrail Apache 632 which has only done around 12000 miles. It has the 2.3l Ducato engine. A few weeks ago the engine management warrning light came on. It simply says "Check Engine". A local mechanic checked the signals and he said it was the exhaust gas temperature warning. He reset the signal and it remained off for a few days and then the warning reappeared. The mechanic said it needed a new sensor. He ordered a new one which proved to have only one wire whereas the original had two. Eventually he ordered the correct Fiat part and fitted it in only 10 mins. I gave the MH a test drive of 20 miles, all OK!

Two days later, on starting the engine, the warning light came back on and stayed on. Also if I start the engine at low revs, the engine will not rev above idling unless I switch it off and restart it at higher revs. The mechanic is so busy he cannot look at it again until Tuesday. I was planning to travel to Spain next weekend for the summer.

Has any one any ideas of other tests I can do in the mean time?

 

[gus-lopez]

No idea but hope someone else might be able to help.

 

[pappajohn]

The OBD fault code may well point to that sensor but it can be anything related to that sensor such as the DPF sensors or even something as simply as a wire rubbing on something to earth.

I had 7 codes relating to glow plugs on my car. The ECU couldn't communicate with the glow module and couldn't see any of the six plugs.

£106 for a new module and £42 for new glow plugs.... Same fault codes.
Obviously a wiring fault... Or is it another sensor, maybe an engine or coolant temperature sensor to tell the module the engines cold.... Who knows.

 

[Carolyn and Kev]

Check out my reply on Lambda sensors on a 2016 Autotrail Apache 634 2016. We found a problem after a £3000 bill (warranty was up to date thank god) due to an issue with the wiring to the ECU. Fiat acknowledged a fault and sorted it . It appeared to be a crimped terminal near to the fuse box Factory fitted!!
The Engine would perform like a good one but the warning light would flash up after 40/60mile. Fiat Italy got involved and found a fault in the wiring at the ECU. Just make sure that yours is checked at the same point. The Lambda sensor was supposedly at fault. 3 new lambda sensors later...crimped terminal fault found by Fiat Italy!
Do not accept the first OBD results.
Ours may have been a one off..yours sounds a little to coincidental to be honest? It could be possible that it is something similar?

Kev

 

[Juggler]

Further to my post above. The Fiat part number is 55272702. There is actually two exhaust sensors. The old one causing the problem is located before the exhaust and looks like a resistor. At room temperature the impedance is 21.8k. In boiling water it drops to 5.8k. I suspect that it is working OK!
I have been thinking of the circumstances when the fault occurs. It seems to happen after the drivers seat has been adjusted or rotated. Is this likely or am I on a wild goose chase?

^{_{Subscribers  do not see these advertisements}}

 

[Carolyn and Kev]

Cant see why the seat would make any difference to be honest? `Then again...could not see the fuse box wiring causing mine!

Kev

 

[Juggler]

Cant see why the seat would make any difference to be honest? `Then again...could not see the fuse box wiring causing mine!

Kev

The sensor is underneath the floor of the van directly below the drivers seat. The sensor cable enters the van through the floor below the drivers seat.

 

[Jonny5davies]

Hi Juggler, did you get to the bottom of this? My 2.3 ducato engine is doing the exact same thing. Had it in to fiat professionals and the same happened. Diagnosed exhaust temp sensor. Replaced it. Still no good. Couldn’t diagnose it

 

[Juggler]

Hello Jonny5davies,
I had amazing troubles finding the problem. All sorts of sensors etc were blamed. It went to 5 garages before the true fault was found. I took it to a Fiat Pro garage who did not rely on the codes from the OBD system. It was caused by damp entering a connector/cable near the nearside wheel arch. Fiat sell a kit to replace the connector with a better one. No problems since.
Good luck

 

[Jonny5davies]

Brilliant thanks for this. I think I know which connector this is. Does it have a grey plastic slide lock on it? I’m thinking I will just solder the wires together and delete the plug

^{_{Subscribers  do not see these advertisements}}

 

[Juggler]

It was some time ago, I think it was blue. The moisture was easy to see.

 

[Juggler]

Hello Jonny5Davies,
Its a month since you were asking about sensor problems. Have you solved your problem?

 

[Jonny5davies2]

Hi juggler. I tried to reply but didn’t have permission so I quickly made a new account. I fixed it thanks to your advice. There was a plug behind the ns headlight that was full of water. I dried it out with an air line then sealed it with tiger seal. Saved me a LOT of money so thank you very much