Overfuel - Misfire in wet - Relay
 

Hi

At my witts end now, been going on for months, car is overfuelling, fuel bangs out the exhaust, can flood the engine so some stops it won't start, in the wet is massively mis fires, and sound of clicking from behind the dash from what sounds like a relay?

Impreza classic import, it's been in a garage 4 times and still not sorted, had a crank shaft sensor fitted, plugs, O2 sensor, IDV cleaned, ECU reset, maf checked, nothing comes up on the black plugs check engine code method?!

Plugs were fitted last year, so was a new temp sensor!

Never known a car so awkward to fix, it's like replace everything until it goes?!

Any ideas?


cheers

Its it running an open cone air filter?

it is mate, has done for the last 4 years, fault only last 4 months or so ;)

When I had my mods done, it originally ran a cone with the OEM MAF. In the pissing rain it used to hesitate terribly when accelerating. I can only assume the water getting on the exposed filter affected the air voltage readings that the ECU thought it was seeing, and fueled incorrectly(?)

All that said, obviously there are plenty who run cone/MAF without any issues.

...Anyway, I'm now on Simtek (MAFless), and that's now all in the past (so yeah, going MAP-sensed air sorted it).


Despite the above, I doubt that's your problem, what with the massive overfueling, etc. Esp. as it's only just happened after c. 3 years 8 months of being in its current configuration.

Seeing as you replaced/checked all the obvious stuff, I reckon your next action is to get it on a rolling road. The operator - assuming he knows what he's doing - will be able to check the logs on the fly, so should be able to get a handle on what's at fault. If you take it to a Impreza specialist with access to a RR, you should be sorted.

thanks for your help mate ;)

I feel for you.

Nothing worse than running issues. Can be a ******* to get to the bottom of.

And all the time, you lose interest in your, once, pride & joy. :mad: :(

I take it you didn't get the code showing up for a failing knock sensor? Just grabbing at straws, really.

It's been fine all this time, the odd sensor but easy to source or came up on the CEL black socket method.

It sure is! spent a small fortune and still nowhere, nothing worse than going to your car wondering if it's going to start due to being flooded!

Read some other threads could be the coil packs, it's something electrical I'm sure, but a garage has had it 4 times and still no progress.

Like you say, a RR might be the way, just need to find one reasonable local ;)

Where are you located?

Done the CEL black plugs method, constant flash so not showing any codes :(

Garage that replaced the O2 sensor said it had completely gone, set me back near 200, and it's no different!

Southport mate

Just realised, the clicking behind the dash.... Have you defo put the plugs back to non-diagnostic/driving (unplugged, IIRC?) mode?!

Yeah mate, only does it that in the wet and mis firing. Clicking from drivers side behind the dash, sounds like a relay, does it in tandem with the mis fire?!

Dry driving, put the clutch in when changing gear, let's off a bang of fuel out the exhaust, some journeys when stop the car, go back to it, won't start due to being flooded.

The clicking, then, could just simply be the boost control solenoid doing it's thing. Although if it is, I'd be surprised if it was that obviously audible.

it's like a derren brown mystery!

cracked or faulting coil pack, can only think it's that?!

Ah, it could be an injector/s receiving (for whatever reason) incorrect info from the ECU, providing too much IDC - hence its rapid clicking (opening and closing), ergo leading to flooding...?


Once again, just throwing it out there...

Derren is a bloody freak. :freak:

So is this fault!! lol

lol

It'd be funny if it weren't so annoying. :(

Checked the CEL code method, finally come up with something!

13, cam shaft sensor, taken it out, cleaned it, still the fault so ordering a new one.

Might be the over fuelling and non start problem, not sure if it's the wet mis fire though?!

But it's something ;)

IIRC, it does indeed provide the trigger for fueling*! So hopefully it is knackered and causing the issue. If so, a relatively painless and inexpensive fix. :)

Fingers and legs all crossed. Whilst touching wood. With the left hand.......

(*I think both the cam and crank sensors provide the triggers for both spark and fueling. Although don't quote me on that.)

i had this before, took ht leads off coilpack and used some vaseline and plugged back it job was a good one.

As per the above post, the misfiring in the rain symptoms is more likely to be down to water/moisture ingress into the electrical system. So try that Vaseline fix as well, ready for the next time it's wet.

If no luck, try to borrow some known good HT leads, to rule them in/out.

good luck fixing it mate, im having a similar problem with mine, non start wet plugs but have spark, gonna change ht leads as ive done everything else, same clicking noise aswell when cranking it, bloody things, so frustrating,

Car has been in the garage about 5 times, some of the faults have stopped but some remain...

Clicking has stopped and misfire, 3 of the coil packs had cracked and the o2 was an after market one soldered, all replaced so must of been shorting out when wet, got a cone induction kit so fitted under trays to stop the wet.

On gear change get a pop out the exhaust, but doesn't do it all the time. Obviously a sign of overfuelling, but tried all sorts?!

new o2 sensor, cam, crank, throttle, new coil packs, spark plugs, yet still signs of overfuelling....

Not replaced the leads, probably the next step but doubtful tbh

Injector getting wet at the top.
I assume they are the older top feeds with a contractor on the top?!
Possibly shorting or something,?