Ecu codes and MAF help

[baz995]

Hi all

drove home today all normal then suddenly car started making a misfire sound and was running really rough then flashing ECU light came on, reading the codes I get

P0101
P0102
P0104
P0108
P0110

A few google searches reveal MAF type stuff, I have taken the MAF off and cleaned it with aerosol tric but no difference. A few questions I have, is it safe to drive as my nearest good scooby mechanic is over an hour away, will it definately be the MAF sensor and if so where would the best place to get one from be?

Many thanks for looking and your help.

[ScoobieWRX]

Before blaming the MAF sensor have a look under the bonnet at all your boost pipes starting from the Turbo and see if one of those pipes has blown off the turbo or intercooler.

Sounds to me like this may be the case.

[baz995]

Hi mate

Spoke to Rowley at Rowleys performance and he suggested the same before i checked back here, so took intercooler off this afternoon and could not find anything wrong. Gave Dynamix a call as he is always really helpful and he said disconnect the O2 sensor to see if there was any difference at all and sadly no. Are there any other pipes other than the intake and intercooler ones i need to check?

Dynamix said the easiest way would be to swap out with a known serviceable one but i dont know any other blob owners in the Yeovil area

[ScoobieWRX]

I'm not sure why Duncan recommended you disconnect the O2 sensor when it's MAF/Pressure related issue just from the error codes.

If you notice your error codes are related to the MAF and MAP sensor. Normally these go off at the same time when you get a split in a boost hose or boost hose blows off, or Air Bypass valve spring dies and won't hold boost.

I presume you are running a top mount intercooler. It's not uncommon for one of the ends of the silicon/rubber Y-pipe to either blow off the turbo or intercooler connections. Equally the short hose at the front of the intercooler that connects it to the throttle body might have a split in it.

I don't think your MAF or MAP sensor are at fault. Put it all back together and make sure all the hose clips are nice and tight.

Put soapy liquid solution into a hand spray bottle. Spray all the boost pipe joins, vacuum pipes and the BOV with the solution. While the engine is running rev it up a few times to make some positive pressure, at the same time look for bubbles where you've sprayed. If you see bubbles you have leaks.

My guess is though if it's running that rough and your problem happened so quickly that you have a big leak and it shouldn't be too hard to spot. 2 of us have given you the same answer so i would be looking in that direction.

[baz995]

Will try that tomorrow mate, many thanks for the post. Whats the going price for a MAF? just trying to gauge my worst case solution!

[ScoobieWRX]

Don't go to a main stealer for it, you'll be robbed blind!!

Have a look online with either a subaru specialist or eBay for a Denso MAF sensor for your scoob, should be about £80-£90 or thereabouts.

ETA: eBay linky.....

http://www.ebay.co.uk/itm/SUBARU-IMPREZA-2-0-WRX-M...

Edited by ScoobieWRX on Thursday 8th March 18:21

[baz995]

legendary mate, that is well cheap. I have been offered one at £75 second hand but its a risk when I am not 100% sure its that so £33 brand new sounds great to me, shame I dont know any other Scoob owners local in Somerset :-(

[ScoobieWRX]

I'm certain there must be other scoob owners or a specialist somewhere in your neck of the woods, or at least within reasonable driving distance/time.

If you get really stuck shout!!

[baz995]

Thanks mate can you think what else it could be other than the MAP if the leak checks come up negative? It runs really rough exactly like a misfire on a normal car. Its my daily drive to work etc so I am pretty stuffed without it

[ScoobieWRX]

If it runs OK off boost upto 3000rpm or so but then runs really badly thereafter, holding back, misfiring, coughing, and not letting you rev much further, specially when you put your foot down and ask for boost, then you have a massive boost leak.

As i said before....when you get MAF and MAP error codes together at the same time and it runs the same as you ahve described it's normally because of a sudden massive boost leak.

Edited by ScoobieWRX on Thursday 8th March 22:58

[JollyGrnMonster]

imho it sounds like a wiring fault..

air temp sensor is in the maf but a separate sensor, the pressure sensor is on the manifold but shares the same 5volt supply voltage..

check all plugs under the bonnet, the bigger plugs behind the battery etc for good clean connections and no water in them.

Simon

[ScoobieWRX]

The MAF sensor shares the same supply as the wastgate solenoid. MAP sensor shares the same supply as the TPS.

[baz995]

ScoobieWRX said:

If it runs OK off boost upto 3000rpm or so but then runs really badly thereafter, holding back, misfiring, coughing, and not letting you rev much further, specially when you put your foot down and ask for boost, then you have a massive boost leak.

As i said before....when you get MAF and MAP error codes together at the same time and it runs the same as you ahve described it's normally because of a sudden massive boost leak.

Edited by ScoobieWRX on Thursday 8th March 22:58

Its rough from start mate and idles like a bag of spanners at around 500 rpm, will do the snoop test today, why is it never easy

[baz995]

JollyGrnMonster said:

imho it sounds like a wiring fault..

air temp sensor is in the maf but a separate sensor, the pressure sensor is on the manifold but shares the same 5volt supply voltage..

check all plugs under the bonnet, the bigger plugs behind the battery etc for good clean connections and no water in them.

Simon

Thanks Simon,

I will admit I groaned when i read the word wiring, what a nightmare, I will have a good look over all the connections today I dont suppose anyone would have a picture of where these bits are?

[JollyGrnMonster]

Check the ecu plugs (passenger footwell) as one of the plugs has those listed on it and if it were lose etc

[ScoobieWRX]

Have you got anything like a hand held OBDII/EOBD diagnostic tester?

[baz995]

you are not going to believe this, took it to Rowleys today and it was the coil pack on no2 cylinder! WTF right? all i can think is that the snap on code reader my local garage used either didnt read right or the codes were wrong. First thing Phil said was its misfiring, read the codes yep all the codes for the MAF etc were there but also No2 cylinder misfire.

Thanks for all the advice and i was glad it was only that great price as well so smiles all round

[ScoobieWRX]

Shame the no2 cylinder misfire code wasn't there at the start

It's pretty odd though that MAF and MAP codes came up. That is definitely a WTF moment!!

[baz995]

definately i do reckon that the original code reader which wasn't a subaru one (flame suit on) didn't read it properly, even looking through the Impreza service manual two of the codes aren't listed. Rowleys used a OE subaru reader and it pulled all the codes out but two of them were different which said no2 cylinder misfire and something else to do with no2 cant remember now. Threaders really as if i had used an OE one first I would have been posting about a no2 misfire!

oil change tomorrow then after running 50 miles with only 3 cylinders running lol thanks again for all your help guys, glad this forum got sorted in the end as some of the other scooby sites didnt even reply

[ScoobieWRX]

It's not just scabbynet or SIDC that have technical resources you can pick the brains of.

The info here is free and we're here to help if we can.

Very glad you got to the bottom of it and it turned out to be an easy and not so expensive fix.

You'll soon be back enjoying your P&J as it should be.

Nice one!!