Cleaning MAP sensor
Discussion
There's nothing to clean really, it's a silicone wafer sensor and as such in 99.999% of cases they either work or they don't. Significant aging can cause the sensor to read low/high for a relative pressure but even this is rare. Total failure is generally a loss of vacuum on the reference side of the wafer or failure in the resistor element of the wafer.
MAF's are a bit different as they majority of those are hot wire or hot film where contamination of the wire or measurement fields can lead to the calibration drifting.... although most modern hot film/dual field ones are pretty resilient.
MAF's are a bit different as they majority of those are hot wire or hot film where contamination of the wire or measurement fields can lead to the calibration drifting.... although most modern hot film/dual field ones are pretty resilient.
MAP sensor is a pressure sensor and is very unlikely to need cleaning to restore or fix it, so apart from wiping the outside to make it look visibly clean for whatever reason - there’s not much you can do to it
MAF sensor is an air flow sensor, which can in some cases be cleaned which will get a bit more time out of it.
MAF sensor is an air flow sensor, which can in some cases be cleaned which will get a bit more time out of it.
Reason for thinking about cleaning these is because I have a very slight hesitation/surge at low speed and slightly rough idle when warm. Not enough to show on the rev counter which is perfectly stable. Almost feels like ECU is weakening-off the mixture too much.
This is on a 90k Peugeot TU5JP4 engine (1.6 16v petrol). Economy wise getting just under 30mpg but that is on an average speed of 12mph so probably about right.
Have got the Lexia-3 diagnostic interface device and software but not sure what to look for in there to help solve this.
This is on a 90k Peugeot TU5JP4 engine (1.6 16v petrol). Economy wise getting just under 30mpg but that is on an average speed of 12mph so probably about right.
Have got the Lexia-3 diagnostic interface device and software but not sure what to look for in there to help solve this.
NickCLotus said:
Reason for thinking about cleaning these is because I have a very slight hesitation/surge at low speed and slightly rough idle when warm.
I don't know your specific car, but in my experience most modern petrol engine cars would be in closed loop mode in those situations. That means they'd be trimming the fuel based on lambda feedback, not just relying on the load sensor(s).The symptoms you're describing are occuring under conditions of high vacuum and might point to an air leak, EGR valve sticking, PCV fault and so on. I wouldn't go 'cleaning' sensors if I were you unless you have got evidence they are misreading.
NickCLotus said:
Have got the Lexia-3 diagnostic interface device and software but not sure what to look for in there to help solve this.
with the ignition on and engine off - get the map sensor reading (in millibar) and compare it to the atmospheric pressure in your area using a weather app.As I said before, there's no "cleaning" of this device to be done.
Turns out it wasn't the MAP sensor but a faulty spark-plug in the new set that I had fitted.
I had replaced the original Bosch FR7MEs with a set of NGK Iridium ILFR6Bs which are listed as compatible and suitable for this TU5JP4 engine. Had only just got the car and so was doing a full service and various other jobs at the same time and hadn't realised that was when the hesitation had started.
Now refitted the old Bosch FR7MEs and runs fine.
Question now is apart from refitting them one-by-one how can I identify which of the new plugs is faulty?
I had replaced the original Bosch FR7MEs with a set of NGK Iridium ILFR6Bs which are listed as compatible and suitable for this TU5JP4 engine. Had only just got the car and so was doing a full service and various other jobs at the same time and hadn't realised that was when the hesitation had started.
Now refitted the old Bosch FR7MEs and runs fine.
Question now is apart from refitting them one-by-one how can I identify which of the new plugs is faulty?
GreenV8S said:
If the problem is specific to a single plug which has been misfiring, I'd have thought it would be apparent from the state of the plug.
Interesting you say that, I would have thought the same but all plugs look fine certainly none that look any different to the rest.Make me wonder if for some reason the Iridium tipped plugs just don't suit this engine but can't see why.
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