Flashing CEL with CAI

[14tooth]

2007 MZ3 2.3 GS

Not saying that the intake is the problem (it more than likely isn't), just mentioning...

After having the intake (PRM - I love this intake!) installed for about three weeks with no problems, today with normal driving, a CEL popped up and immediately the throttle response was terrible. Sputtering was audible and there was noticeably less power. Shortly after that, and trying to accelerate, the CEL began to flash. When I brought the car to a stop, the RPM dropped a lot lower than it ever has before - about 400-500. I took a look at the intake first and all fasteners and hoses were all in tact.

I'm sure there's a lot more to this than the intake at this point. Thanks for any input.

[shu5892001]

Just get the code scanned...

[Donutz]

You have a torn wire in your maf harness somewhere; guaranteed. Where are you located?

[bluemazda3]

might be maf sensor... I had that before on my old car.. but it was my mistake... i put one part backwards and it was like the car had hiccups..:bang

[14tooth]

You have a torn wire in your maf harness somewhere; guaranteed. Where are you located?

I'm in Halifax Nova Scotia, no where close to the GTA unfortunately. I haven't had an OBD reader on it yet. When I installed the PRM intake, I made sure the cables attached to the MAF were detached from the battery box (as per Gerry's instructions). Sounds like a lengthy process in finding where a tear may be in the MAF harness?

Thanks for the input guys.

[14tooth]

Reading a bit more into the MAF harness and wiring...

I'll check to see if any wires running to the harness are weakened or torn due to the CAI's position and movement. I figured that because of the relatively high placement of the MAF on the PRM intake that I wouldn't have this problem, but there is a lot of engine movement and movement on the intake itself when driving. Will report back....and hopefully won't have to scour the east coast for a junked 3 that I can steal the harness out of!

Any more input is greatly appreciated!

[Donutz]

It's easy to fix. Don't bother buying a new harness, just replace the broken wire.

[MajesticBlueNTO]

a flashing CEL is an engine misfire and usually means "shut the car off now!"

was it raining heavily while you were driving? possible that drops of water got sucked into the intake and choked the MAF causing the sputter then a misfire code?

get the code(s) read first. I guarantee you have a misfire code for one or more cylinders... but there may also be another code stored with it that precipitated the misfire.

you could have anything from a broken MAF wire to a faulty ignition coil.

[Triniboi]

I can almost gurantee you it is the wiring connecting to the wire harness before it plugs into the MAF sensor harness. You have to first check the code, if your getting a engine code p0102 its your MAF. Possible two of one is happening. The most likely cause;was when installing the intake, you had pulled the sensor wiring too hard and ripped on of the wires off the inner pit of the connector(which you need to now get soldered back on, about a $200 job), or you can replace the whole under hood wiring for $1300 which only mazda sells. Second issue would be the actual MAF(highly doubt it), which would need to be replaced, which sells at mazda for $120.00. Id first check the wiring.

hope this helps

[Donutz]

It'll cost him less than $1 if he diy's.

[Triniboi]

Of course, if hes got the correct equip.

[14tooth]

Thanks for all the great input. Here's how things transcended when I got off work.

It was raining this morning when I got that blinking CEL, however this isn't the first time in rain and this isn't the heaviest rain i have driven in with this intake. After researching the wire harness situation with the MAF, I came across a thread describing how to fully remove the pins and wiring from the harness itself. I did so, and removed every wire individually and found that none of the wires were damaged either at the connector pin or all the way down to the housing junction in front of the battery. I then re-installed the MAF and ran the car while jiggling each wire individually. None of the movement in the wires changed how the engine idled. After some frustration, I put the harness and MAF back together, re-installed on the intake and headed for princess auto/CT and picked up both MAF cleaner and a OBD II. Finally had everything and jumped back in my car, drove 30 feet in the parking lot and POOF - CEL disappeared. I should mention, I wasn't cranking past 3k on this whole drive to get the materials. Got home, removed MAF and sprayed down sensor (while removing o-ring before hand), let it dry out and re-installed. Went for a cruise, low RPM's for 1/2km, then back into the 5-6k region with no problems.

One more thing I just thought of: I've been running the battery vent over top of my PRM intake since I installed it. It does touch the top of the MAF unit, but does not put any significant force on it. All the driving I did today after the initial blinking CEL, up until I sprayed down the MAF and re-installed, was done with the battery vent off. Could this have anything to do with it somehow? I don't see how it could considering it doesn't even come close to touching the wiring....I guess time will tell.

Like I said, no visible damages or anything on the wiring. The MAF was indeed dirty on the intake side and had never been cleaned in its 73,000 KM lifetime. At least I learned about my MAF today!

[McGuyver_3]

No the battery vent would not have an affect on this.
The engine light is deffinatly a missfire code next time it comes on scan it and see. Sounds like something got a touch of moisture in it. Hate to say it but it does happen

[14tooth]

Back out on the road today, tried cranking up a hill in second gear and the same thing happened again, even though last night everything seemed fine after I cleaned the MAF sensor. Got to use my OBD II reader and found that I'm getting P0301and a pending P0301: Cylinder 1 Misfire detected. So by the code I'm getting, it has nothing to do with the MAF. UGH.

Time to start looking into coils, spark plugs, wires blah blah.

[14tooth]

Have any of you guys experienced this problem before? If so, were you able to pin point the issue?

Thanks again.

[McGuyver_3]

Have any of you guys experienced this problem before? If so, were you able to pin point the issue?

Thanks again.

Take out coil pack number 1 switch it with number 2 coil pack and switch spark plug 1 with spark plug 3. This will be your easiest way of seeing if you have a plug, coil or other bigger problem the quickest

[14tooth]

Take out coil pack number 1 switch it with number 2 coil pack and switch spark plug 1 with spark plug 3. This will be your easiest way of seeing if you have a plug, coil or other bigger problem the quickest

So, are you saying that if I move coil pack 1 to 2, and spark plug 1 to 3, that if I see a misfire on a different cylinder after the switch, that it is likely the coil pack 1 and spark plug 1? Or would all of them need replacing? Thanks.

[Dave_The_BMXER]

I just fixed this but with cylinder 4.

Do what McGuyver said, move the coil first, see if the code jumps. If yes bad coil if no try with plug and see.

Or you can start with the plug first. Mine ended up being a bad plug in cylinder 4.

[McGuyver_3]

So, are you saying that if I move coil pack 1 to 2, and spark plug 1 to 3, that if I see a misfire on a different cylinder after the switch, that it is likely the coil pack 1 and spark plug 1? Or would all of them need replacing? Thanks.

No what I am saying is, do all these 3 steps i stated as you will get the quickest results with the least amount of work and you are covered on all your fronts in 1 shot. if the missfire goes from 1-2 then coil is bad if missfire goes from 1-3 then the plug is bad if the missfire stays in cylender 1 then check wiring or do a compression test

[14tooth]

I pulled coil and plug one to find a horrific looking scene of corrosion and liquid. The corrosion was brown and the liquid had no scent whatsoever. The bottom of the cylinder was noticeably dirty as well. I pulled the other three for comparison and they were all clean as could possibly be. I asked a friend who is a mechanic what the liquid could be, he says its possibly from hosing down the engine bay, which I did do once. There was not a great deal of liquid in the cylinder, but if it was from the engine bay washing, it had been there for a couple months.

I pulled everything out of cylinder 1, cleaned and blew out the liquid with air, cleaned up the coil and plug and replaced with electrical white grease. I managed to get almost all of the corrosive soot off the walls of the cylinder, plug, and coil. Put it all back together and went for a 20 km drive, starting off slow and ramping up as I went, trying to recreate the problem, and I couldn't.

I'll keep at this to see if the problem comes back, hopefully that liquid was just water from when I cleaned the bay.

Thanks again guys for the help!