Engine Hunting after Battery Swap - help
#1
Engine Hunting after Battery Swap - help
Hello all, had a really bad day today.
I just nipped to the petrol station on my break at work, filled up with petrol and the car wouldnt re-start.
Couldnt get it going so phoned up the RAC - bloke said the battery was knackered, one of the worst hes seen for a while and probably the original battery ( cars a MY99 UK Turbo - so 8 years old ).
I then took it to a garage and had a new battery fitted - I did this straight away as he couldnt guarantee the car would start again after switching the engine off.
New battery fitted - car starts / runs sweet. I drive home and upon pulling into my driveway i notice the engine is hunting - anything from 1200 rpms to 400 rpms - the car doesnt stall at all and runs excellent but its started this hunting all of a sudden.
Whats caused this sudden problem? All ive done is change the battery for a new one - and the bloke said it was the correct battery for the car.
Anyone any ideas as im getting fed up with the whole thing and ive had a ****ty day to boot.
Any help would be appreciated, sorry for the long post.
Adam
I just nipped to the petrol station on my break at work, filled up with petrol and the car wouldnt re-start.
Couldnt get it going so phoned up the RAC - bloke said the battery was knackered, one of the worst hes seen for a while and probably the original battery ( cars a MY99 UK Turbo - so 8 years old ).
I then took it to a garage and had a new battery fitted - I did this straight away as he couldnt guarantee the car would start again after switching the engine off.
New battery fitted - car starts / runs sweet. I drive home and upon pulling into my driveway i notice the engine is hunting - anything from 1200 rpms to 400 rpms - the car doesnt stall at all and runs excellent but its started this hunting all of a sudden.
Whats caused this sudden problem? All ive done is change the battery for a new one - and the bloke said it was the correct battery for the car.
Anyone any ideas as im getting fed up with the whole thing and ive had a ****ty day to boot.
Any help would be appreciated, sorry for the long post.
Adam
#2
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it sounds to me like a mass air flow sensor fault. this would my first point off call...
#6
How much are these Mass Air Flow sensors? And is it a complete thing that i need or just a particular part?
Suppose a subaru garage is the only place to get one quickly?
Lastly if i need to order one of these things, am i safe using the car? - seeing how it runs perfectly well ( apart from the hunting at idle ).
Adam
Suppose a subaru garage is the only place to get one quickly?
Lastly if i need to order one of these things, am i safe using the car? - seeing how it runs perfectly well ( apart from the hunting at idle ).
Adam
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Yup it does point toward the MAF sensor.
We can soon confirm it on the diagnostics either way.
£75 + vat from us.
Driving it normally would be prudent until it's sorted
Andy
We can soon confirm it on the diagnostics either way.
£75 + vat from us.
Driving it normally would be prudent until it's sorted
Andy
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#8
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hi i just bought a maf for my 99 £75+vat from subaru dealers but didnt sort my prob so if u want ill sell u my old one as its perfectly fine
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if you run a standard air inlet i would stick with the oe item, can change to othere make if you run a after market ecu
mark
p.s sorry for slow posts but i'm in the car on the way to france
mark
p.s sorry for slow posts but i'm in the car on the way to france
#11
Hia mate, i run the standard airbox with improved panel filter as id been told an aftermarket could upset the car.
I suppose most Subaru dealers have these things in stock constantly? Would i be able to take the car to my nearest subaru dealer and ask them to temporarily fir the sensor to see if it solves the problem - or do they not like doing that? Would they rather just take your money.
Dont worry about slow posting mate - im not gonna use the car again till the morning anyway.
Adam
I suppose most Subaru dealers have these things in stock constantly? Would i be able to take the car to my nearest subaru dealer and ask them to temporarily fir the sensor to see if it solves the problem - or do they not like doing that? Would they rather just take your money.
Dont worry about slow posting mate - im not gonna use the car again till the morning anyway.
Adam
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if it was me i would cheak that the air filter is a oil fee (dry) type filter. some air filters are oiled..
if the filter is oiled then it can sometimes can contaminate the maf sensor
if the filter is oiled then it can sometimes can contaminate the maf sensor
#13
OK mate, ill have a look at the filter - although im sure its not this as the current panel filter's been on the car about 8 months and this is the first time ive had problems with the car.
Anyone know the closest Subaru Parts dealer to Warrington? Used to be one in Northwich but not sure its still there or not.
Thanks
Adam
Anyone know the closest Subaru Parts dealer to Warrington? Used to be one in Northwich but not sure its still there or not.
Thanks
Adam
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the reason it is most likely the maf sensor is that the ecu learns to the failing maf sensor and adapts as it fails slowly.. then you disconnected the battery long enough for the ecu to forget it's settings and therefore run with the classic failed maf sensor sympthoms on the new battery..
#17
Christopher Neil didnt have one in stock - then they tried to fob me off saying i needed to buy the full unit - £160's worth stating that "my model of car needs the complete unit and not just the sensor" !!!
Anyway ive sent a few pm's to try to get one off here for a reasonable price.
Powerstation - youve got PM
Thanks
Adam
Anyway ive sent a few pm's to try to get one off here for a reasonable price.
Powerstation - youve got PM
Thanks
Adam
#18
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What they said at Christopher Neil is complete ****e. Haven't looked at all the posts in this thread but just incase anyone hasn't said it - don't gun your car till the maf is sorted as it's possible that your £75 bill may turn into a £3k one
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Christopher Neil didnt have one in stock - then they tried to fob me off saying i needed to buy the full unit - £160's worth stating that "my model of car needs the complete unit and not just the sensor" !!!
Anyway ive sent a few pm's to try to get one off here for a reasonable price.
Powerstation - youve got PM
Thanks
Adam
Anyway ive sent a few pm's to try to get one off here for a reasonable price.
Powerstation - youve got PM
Thanks
Adam
Would probably be better to call though.
01684 296675.
Andy
#20
Hia mate, thanks for that.
I'll give them a shout on Monday then and see if i can get one sorted. Any idea how long delivery takes on one of these?
And are they relatively easy to fit?
Looks like ill be leaving my car at home for a few days next week so i dont cause any damage to the car.
Adam
I'll give them a shout on Monday then and see if i can get one sorted. Any idea how long delivery takes on one of these?
And are they relatively easy to fit?
Looks like ill be leaving my car at home for a few days next week so i dont cause any damage to the car.
Adam
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Hia mate, thanks for that.
I'll give them a shout on Monday then and see if i can get one sorted. Any idea how long delivery takes on one of these?
And are they relatively easy to fit?
Looks like ill be leaving my car at home for a few days next week so i dont cause any damage to the car.
Adam
I'll give them a shout on Monday then and see if i can get one sorted. Any idea how long delivery takes on one of these?
And are they relatively easy to fit?
Looks like ill be leaving my car at home for a few days next week so i dont cause any damage to the car.
Adam
to remove is easy, pull off wiring plug and undo two screws.
As I stated earlier though and also the last poster comes back to it but on a different tack.
You should get it checked to confirm it IS definitely the MAF before spending £75 quid!
Andy
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[Davey] I agree, But i think that you'll find that this one is genuine. I had exactly the same problem with my year 2000. The clinic did explain why disconnecting the battery (or going flat) causes this problem but TBH i anit got time to put it in to text.
#26
OK, well what sort of places could i take the car to have it checked over - and to make sure its definately the MAF sensor?
Im not sure its something your average garage would have a clue about!!
Adam
Im not sure its something your average garage would have a clue about!!
Adam
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You could try reading your fault codes but it might not show up but its a start,
Read Memory Mode
Ensure ignition switched OFF
Connect Engine Diagnostic Link connectors (Black)
Switch ignition ON, DO NOT start engine
Check that CEL illuminates
Count CEL flashes
Troubles codes are indicated as follows
Long flashes indicate the tens of the trouble code
Short flashes indicate the units of the trouble code
A short pause separates each flash
A long pause separates each trouble code
Switch ignition OFF
Disconnect engine diagnostic link connectors (black)
Dynamic Check Mode
Engine at normal operating temperature
Ensure ignition switched OFF
Connect engine diagnostic link connectors (Green)
Switch ignition ON. DO NOT start engine
Check CEL illuminates
Start engine
If CEL does not flash: Drive vehicle for 1 minute minimum at 7mph minimum
Increase engine speed to 2000rpm minimum for 1 minute minimum
Count CEL flashes
Troubles codes are indicated as follows
Long flashes indicate the tens of the trouble code
Short flashes indicate the units of the trouble code
A short pause separates each flash
A long pause separates each trouble code
Switch ignition OFF
Disconnect engine diagnostic link connectors (Green)
The ECM fault memory can also be checked using suitable diagnostic equipment connected to the data link connector (Yellow)
Erasing Trouble Codes
Engine at normal operating temperature
Ensure ignition switched OFF
Connect engine diagnostic link connectors (Green and Black)
Switch ignition ON. DO NOT start engine
Check the CEL illuminates
Start Engine
Drive vehicle for 1 minute minimum at 7mph minimum
Increase engine speed to 2000rpm for 1 minute minimum
Check that CEL flashes: Code 11111. No fault found
Switch ignition OFF
Disconnect engine diagnostic link connectors (Green and Black)
Trouble Code Identification
Trouble Code - Fault Location
11111 - No Fault Found
11 - Crankshaft Position Sensor
12 - Starter Switch
14 - Injector 1
15 - Injector 2
16 - Injector 3
17 - Injector 4
21 - Engine Coolant Temperature Sensor
23 - Mass Air Flow Sensor
24 - Idle Air Control Valve
31 - Throttle Position Sensor
32 - Heated Oxygen Sensor
33 - Vehicle Speed Sensor
35 - Evaporative Emission Canistor Purge Valve
49 - CO Adjustment resistor If Fitted
51 - Neutral Switch (MT)
Or you could act on the advise given by other members with the same problem
Read Memory Mode
Ensure ignition switched OFF
Connect Engine Diagnostic Link connectors (Black)
Switch ignition ON, DO NOT start engine
Check that CEL illuminates
Count CEL flashes
Troubles codes are indicated as follows
Long flashes indicate the tens of the trouble code
Short flashes indicate the units of the trouble code
A short pause separates each flash
A long pause separates each trouble code
Switch ignition OFF
Disconnect engine diagnostic link connectors (black)
Dynamic Check Mode
Engine at normal operating temperature
Ensure ignition switched OFF
Connect engine diagnostic link connectors (Green)
Switch ignition ON. DO NOT start engine
Check CEL illuminates
Start engine
If CEL does not flash: Drive vehicle for 1 minute minimum at 7mph minimum
Increase engine speed to 2000rpm minimum for 1 minute minimum
Count CEL flashes
Troubles codes are indicated as follows
Long flashes indicate the tens of the trouble code
Short flashes indicate the units of the trouble code
A short pause separates each flash
A long pause separates each trouble code
Switch ignition OFF
Disconnect engine diagnostic link connectors (Green)
The ECM fault memory can also be checked using suitable diagnostic equipment connected to the data link connector (Yellow)
Erasing Trouble Codes
Engine at normal operating temperature
Ensure ignition switched OFF
Connect engine diagnostic link connectors (Green and Black)
Switch ignition ON. DO NOT start engine
Check the CEL illuminates
Start Engine
Drive vehicle for 1 minute minimum at 7mph minimum
Increase engine speed to 2000rpm for 1 minute minimum
Check that CEL flashes: Code 11111. No fault found
Switch ignition OFF
Disconnect engine diagnostic link connectors (Green and Black)
Trouble Code Identification
Trouble Code - Fault Location
11111 - No Fault Found
11 - Crankshaft Position Sensor
12 - Starter Switch
14 - Injector 1
15 - Injector 2
16 - Injector 3
17 - Injector 4
21 - Engine Coolant Temperature Sensor
23 - Mass Air Flow Sensor
24 - Idle Air Control Valve
31 - Throttle Position Sensor
32 - Heated Oxygen Sensor
33 - Vehicle Speed Sensor
35 - Evaporative Emission Canistor Purge Valve
49 - CO Adjustment resistor If Fitted
51 - Neutral Switch (MT)
Or you could act on the advise given by other members with the same problem
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the reason it is most likely the maf sensor is that the ecu learns to the failing maf sensor and adapts as it fails slowly.. then you disconnected the battery long enough for the ecu to forget it's settings and therefore run with the classic failed maf sensor sympthoms on the new battery..
And be thankful...that dead battery may have saved you the cost of an premature engine rebuild
(depending on how long its been running with a semi-failing sensor and how its been driven with it in that state).
If in any doubt find a freind with a MY98 to MY00 car and swap it to see if it works
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Find an ecutek dealer or someone with access to the diagnostics port, either with deltadash (ecutek) or the Select monitor (Subaru) May be others as well but not so sure,
Reading fault codes wont tell you a thing unless it completely fails.
Someone worth their salt will be able to see what "load" it's reading and tell you whether it's FUBAR or not.
Reading fault codes wont tell you a thing unless it completely fails.
Someone worth their salt will be able to see what "load" it's reading and tell you whether it's FUBAR or not.