Did something explode?

[tone]

Hey y'all,

Was driving to work this morning. Gave the car some minor acceleration getting to about 2500rpm in second gear. The car proceeded to violently shudder. Quickly changed to third and it smoothed out but i didn't really give it any stick. cruised for maybe another 10 minutes keeping under 2500rpm.

Tried again second gear 2500+ rpm and i hear a loud POP/bang and my CEL came on. sounded like it was a massive back fire. No shuddering or anything. Had a quick look in the engine bay once i got to work. No smoke and couldnt see anything leaking (driveway was wet so would be hard to tell anyway) There was a slightly funny smell in the cabin but that went away after 10 seconds.

Any ideas what this could be? should i possibly take it to a service ctr/mechanic asap?

Its a 2007 MPS. TBE, Xede, BOV, Inlet pipe. Hoping its something trivial like a carbon build up as god knows when that's last been cleaned.

having said this, i did drive through an insane puddle last night. Is it possible the CAI got wet? (Even though it sat overnight outside it should have dried) its the CPE one that sits fairly low to the ground behind the left wheel.

[chef]

That's sounds really bad it's a very big possibility the filter got wet.
Also it is not a good idea to be driving with your mods untuned either.
Driving a car with your mods untuned is a bad recipe

[tone]

It felt pretty bad.

oh no i had it tuned with the Xede.

Could it be possible the spark plugs are on the way out too?

[SarcasticOne]

Holy shit you're alive...

+1 to wet filter and MAF...
If possible pull the filter out and the MAF sensor, leave them to dry over night

[chef]

I have never been a fan of CAI for this reason.

[Rayd]

Was it a continuous shudder ? Or one large jerk? If continuous shudder then +1 to wet MAF

[tone]

Was it a continuous shudder ? Or one large jerk? If continuous shudder then +1 to wet MAF

The first time it happened was 1 large shudder. The second time it was a huge bang but no shudder.

[Rayd]

When the MAF gets wet it will run super rich,
This can cause a massive backfire?
Have you tried driving it l?

[SarcasticOne]

The first time it happened was 1 large shudder. The second time it was a huge bang but no shudder.

Hopefully just a wet MAF causing excessive fuel to be injected into the car
Rich condition = back fire

[tone]

When the MAF gets wet it will run super rich,
This can cause a massive backfire?
Have you tried driving it l?

after the first shudder i drove it. It Idles fine and accelerates fine. but come 2500 - 3000rpm is when it backfired like a mother.

When you say MAF you mean the little sensor in the housing attached to the intake pipe? could water make its way all the way up to that point?

My spark plugs are roughly 4 years old too. Last service (6months ago) suggested i changed them soon. Could this be a possibility? I know id have to take the top mount off to check them but can i check them visually without removing them? or should i just wait until Friday when im having my service done?

[Doug_MPS6]

Agree re the usual CAI fitment - Why for the sake of a few degrees of temperature, anyone would anyone stick their induction plumbing as low as possible where it can hoover up dust from the dustiest place possible - in the wheel-arch - along with debris and water off the road, has me beat. Stick with the shorter plumbing of an SRI, there is less plumbing to clutter up the innards of the engine bay, less plumbing resistance to airflow, less vibration, fewer mounting points to rattle and crack and cold air can still be brought in directly from the front, with perhaps greater ram effect, considering that the wheel arch is a known low-pressure zone, fighting your induction system all the way.

Big bangs from over-fuelling can warrant a check of the exhaust system and cats and O2 sensors too. But dry everything (CAI filter & MAF) out and reassemble and test start and run. Let it idle to warm up before applying revs. If it settles to a smooth idle in the warm-up you should be OK.

[STEALTH_MPS]

+1 to it been the maf and filter. Also don't just take the filter off. take the whole intake off as well as water may be lodged in the elbow thats near the filter. Happened to mine when i had this cai.

[SarcasticOne]

after the first shudder i drove it. It Idles fine and accelerates fine. but come 2500 - 3000rpm is when it backfired like a mother.

When you say MAF you mean the little sensor in the housing attached to the intake pipe? could water make its way all the way up to that point?

My spark plugs are roughly 4 years old too. Last service (6months ago) suggested i changed them soon. Could this be a possibility? I know id have to take the top mount off to check them but can i check them visually without removing them? or should i just wait until Friday when im having my service done?

Yup, that's the one! It doesn't take much, 1-2 drops of water will cause all sorts of weird readings.
Can probably get by without the spark plug check until service

[gurusev]

Same Happened to my evo aswell. Get rid of cai or get a custom build box for it. Also I would suggest bpv over bov but that's just my personal preference..

TAP DAT!!

[tone]

Thanks for the replies. Im going to have to drive it home from work today. Will take it easy on the drive home then dissasemble and dry out. The MAF housing is a bit of a problem. The little screws that hold it in place seem to have rusted and the shape of the little screws is circular without the edges for a tool to catch and turn.

[Adriano]

Same thing happened to me while diving to a track day. I drove through some very intense rain during a storm - when I started getting onto boost it would shudder. By the time I arrived it had resolved itself and the car ran perfectly on the track. I inspected my SRI and found some water but seemed to have dried enough to come good. When I got home I changed the air filter and cleaned the MAF. No problems since.