2.0 gti AGG misfire

[soniquethedog]

hello , i have a 2.0 gti mk3 AGG engine fitted to my ex 1.6 jx 1981 devon , it has been running well for 10 months an has developed a kind of misfire when under load going up hills or when i put my foot down , it seems ok at low revs , when plugged into to a fault code reader the fault came up as hall sender out of range , any ideas ? cos its like driving my old jx again : (

[Titus A Duxass]

I've had the same problem - the MAF is probably dirty.
Taken it out out of the housing and clean the two filaments with carb cleaner, do not physically touch the filaments.

Mine gave an error for the intake temperature sensor.
I had a good clean tick over and it would rev cleanly when not under load.
Coughed and splutter like a Capstan smoker under load (uphill or accelerating).

[Kermit'skeeper]

Haven't come across this before but the fault code sounds like a distributor problem. Any chance the timing could have moved?

[Titus A Duxass]

My thinking is that with a dirty MAF the engine/ECU is confused.
The engine is running bad but everything sensor wise is working but the feedback to the ECU shows that something is off kilter.

Mine tells me that the Intake Air Temp sensor is at fault, it's not - I've checked and replaced the sensor and I've checked the wiring back to the ECU.

Mine was caused by running with a dirty K&N filter.

[Kermit'skeeper]

The readings from the MAF and intake air temp. sensor are used in the same calculation by the ecu to work out the volume of air being drawn into the engine. The ecu doesn't know the maf is dirty but it knows the readings from the two sensors don't make sense which is why you were getting the intake air fault code. Later maf's have the intake air temp sensor built into them.

[Titus A Duxass]

Aah thank you.
You've confirmed my thoughts.

[soniquethedog]

i disconnected the plug for the MAF and took it for a test run up a steep motorway near me and it run really well and was back to normal 75-80 no probs , so i guess it needs cleaning or replacing , thanks for the help

[Titus A Duxass]

i disconnected the plug for the MAF and took it for a test run up a steep motorway near me and it run really well and was back to normal 75-80 no probs , so i guess it needs cleaning or replacing , thanks for the help

Good to hear.
Give it a good clean and you should be okay but.....YMMV

Some say that you should never clean the MAF......I've done it once with no problems.