Intermittent Engine Light Problem
 

Hey guys,

I finally got out of bed yesterday at about 12 and decided to get some KFC with a couple mates. Warmed the car up as usual and just cruised down the street. After about 3 minutes of casual driving, my check engine light flashed on for 1-2 seconds and then went off again. As this happened, my car seemed to lose all power, as I was steadily accelerating from traffic lights at the time, and then it kicked back in suddenly. I was like wtf just happened?

So I kept driving down the street, and then about 30 seconds later, it did it again. So I took the next turn off and drove straight back home before anything else happened, as I had no idea what was going on. On the way back it did it a further 2 times.

It's a '98 wrx, had an engine change about 1-2 months ago, and tuned with power fc through asg.

I'm yet to ring ASG or anyone about it, so I though I'd ask for your opinions first. Has anyone had this happen or know what causes this?

I had the exact thing happen to me a year ago, when I lost all power and then have it kick back in suddenly, in my old car. But that was when I was incredibly low on fuel from a trip up north. And no engine light came on. Except this time I had half a tank and the light coming on. So I thought maybe I have a dodgy walbro pump? But a guy from work thinks it's knock, and to check my hand controller. Unfortunately my hand controller died on me a couple months ago so I can't check.

Any info would be much appreciated,

Thanks, Sam

Afm...


This is what happened when mine went.. Hated boost and idled roughly...

Thanks for that. Would a shit afm cause the car to go up in revs when i take my foot completely off the accelerator. Example would be last week i was driving back from burswood going 60, stopped accelerating so the revs dropped to say 1500, then automatically went up to 2000, then down again, then back up. I was keeping a constant 60 due to that happening lol. I wouldn't have a clue what causes it.

As you can see I'm still learning what causes different problems lol

If its a stuff afm your car will hunt at idle, from what your saying it doesn't?

hessitation getting onto boost also another symptom of failing AFM

I would just take it back to who tuned it and get them to have a look, MIL came on so should be a fault code stored. A faulty AFM can cause cutting out, poor performance, and hunting at idle, but for it to swing between 1500-2000rpm, never seen that, sounds more like an idle stepper motor issue.

afm for sure

power fc only shows engine light when something is out of range aka afm voltage

exact thing happened to me 1 week ago

[QUOTE=MattuZ;552722]afm for sure

power fc only shows engine light when something is out of range aka afm voltage

exact thing happened to me 1 week ago[/QUOTE]

Matty FTW, still more posts then you though:p

well i took it for a quick spin last night, and again just then to my brothers house. he had a quick look and took it 4 a spin himself. and nothing. was running perfectly.

found out the controller has a very loose connection and that's why it wasn't working lol i've been too lazy to check it myself. and from that, there's nothing out of the ordinary. no knock, and boost comes on fine..

it does hunt at idle on occasion.. and does that random thing where it revs itself as i said before, but probably once a week? other than that, i've had no problems before or after that incident yesterday.

i'll have to get the afm checked out as quite a few of you suggest that must be it.

I am lead to believe that the afm on the 98s are not as common to stuff up as the 99/00 models. Unfortunately they are also more expensive.