Car Wont Start any idears? [idel/hunting]
 

Been bizzy all day getting my car ready for the ra meet has been off road for a weekhttp://www.scottishscoobies.net/imag.../RpS_angry.gif as needed pads got them on today took it out for a spin bed them in noticed the car was haunting quite badhttp://www.scottishscoobies.net/imag.../RpS_angry.gif i took it home went up to ma m8s and back left my turbo timer on.I heard from ma house car was bearly tiking over then cut out went back out started it but was bearly tiking over tryed reving it had no effect any idears?http://www.scottishscoobies.net/imag...S_confused.gif
anyone had this happen? need this fixed in time for the meet i was told theres a way of reading the flashes as fault codes?

Ive now tried replacing the crank sensor and sensor under the alternator with no joy there is no fault code ive checked this now as well:confused:
there has been some slight idle problems on going recently and had got worse and now resulting in it not starting now ive not tried the temp sensor yet:mad:

all help/comments will be very appriciated http://www.scottishscoobies.net/imag...pS_thumbup.gif

Anyone?

MAF?

Maf or temp sensor and its over fueled it and flooded it. you need to establish that it has fuel at the fuel rail. injector pulsing and spark

ideal control valve

Tested the maf seems to be fine getting fuel and a spark as its tries to start does for bout 2 secs if patient enough at trying so its down to something like the idle control or the temp sensor i will eliminatchange them and replace maf hope that works al post my progress thanks alot for your help so far

IDLE! It's an IDLE control valve:rolleyes: It controls the car's IDLING!

Hang on, hang on.............you "tested the MAF" how?

AFAIK unless you have access to sophisticated test equipment and computers, there IS NO TEST for a MAF.

Do a search on here if you don't believe me.

The old idea of disconnecting it? Rubbish.

yes i'm dyslexia SORRY

Anyone else any advice still a non runner

Knackered ecu? Mine packed in and the car wouldn't start.

MAF or idle control valve wont stop it from starting. It may run rough if theyve failed but should still start. possibly a fuel pump problem from what you describe

So HAVE you tried a new MAF?

isnt a maf just a resister which can be tested by a decent electrical meter,

just test the resistance ? dont know for sure,

No, because it's supposed to vary with pressure of air passing over it, it then "meausures" the mass of the air flowing into the engine.
Mass Air Flow: MAF

So, as I said, unless you have access to accurate measuring equipment and KNOW what you are doing, there is no test.

Over the years I've seen many people come out with this idea of unplugging it with the engine running, and it's a myth.

Sorry.

Thats rubbish to be fair. Changed the MAF on alot of cars after using this method and solved the issue the car was having every time.

If the car is driven with the MAF working it will stall/ nearly stall when the MAF is unplugged. If the MAF has failed disconnect the plug and car continues to idle = MAF failed

The MAF is used to calculate the volume of air which is going into the engine as is the MAP sensor. A calculation is carried out for the injector duty/ignition to be set correctly for the load on the engine.
The car learns to run only using the MAP sensor when the MAF fails and therefore the car does not stall when it is disconnected.

Oh, right, so tuners like Harvey, David at API, Allan Jeffery are wrong then?

Whatever mate.

if it was the maf then it would through up a code has it ?

maf are very prone to fail but yes do flash up cel lights have you searched around for any loose pipes ??

are the plugs getting wet when cranked over ?

if it happens to have a vta dv also check this is closing

Not saying they are wrong. Maybe through experience they have found it is not a reliable way of diagnosis thats up to them.
I will continue to use the disconnection method as it has worked for me so far :p

coilpack leads or coilpack!!!!!!!

Jeez, I wish splitpin was here so he could put this one to bed AGAIN.

Lol settle down boys stick to the subject thanks for helping everyone by the sounds of it i need to replace everything i wasent wanting to buy all auxillarys for a subaru just the faulty one

But the unplugging thing at idle is ONLY measuring airflow/voltage at partial vaccum/idle - and NO other load/rpm situation.

At idle it's not an issue, as there's no arduous conditions happening for 'the engine to worry about'.

If, however, the supposed 'good' MAF's sensor dropped voltage at high load/rpm or WOT, then it could be curtains for the motor due to transient lean AFRs! This is what the "unplugging at idle test" CANNOT determine.

As alcazar has eluded to, Splitpin has covered this in detail in many threads... ;)

Thanks joz, I need to copy that explanation.
It's amazing how many times you see that myth come up. I wonder how many engines have gone pop because of it?