[MonsterEnergy]

Hello all - wee bit of help required please.
I've had the check engine light on MY03 4200GT Cambiocorsa for a small time.
If I reset it - it will stay off for a few hours then come on again.
However, today it blinked 20 times while it was on.
Still seems to be driving ok - if maybe a bit noisy.
Is the 20 symbolic of a specific fault?
I'll try to get an OBDII to plug in during the next couple of days to further diagnose it.
But in the meantime - any help much appreciated.
Is it ok to drive as long as I don't thrash it?

[mcarjr]

I would NOT drive the vehicle. A flashing CEL is very serious and means something with the catalytic converter, I believe. This can be very dangerous.

[mcarjr]

It could also be spark plug wires. I would get it taken to a dealer for inspection, for sure.

[rotorheadcase]

Generally I would agree, however with the Maseratis the CEL could be anything from a leak in the intake system, a ,sensor malfunctioning an intermittent electrical fault or as simple as a loose wire connection. A problem with the cat will usually bring on a "slow down" light as well. They don't have plug wires as such, the coil pack is on the spark plug itself, however the coil pack is often a culprit for CEL's.

It's your call wheth to drive it but if it were mine and there did not appear to be any other symptoms associated with it, I would drive it albeit very carefully. The engine management system will normally go into limp mode if a failure has the potential to do major damage.

A priority is to have the codes read and the problem diagnosed.

Hope this helps,

Neil

[Tubber273]

Originally Posted by rotorheadcase

A priority is to have the codes read and the problem diagnosed.

Hope this helps,

Neil

That's the best advice...get an OBD2 reader.
Side note: I was told by the techs at the dealership that (generally) a flashing CEL in indicative of a random misfire, which I've had.
Same thing would happen - re-set computer - light goes out - all is well (for awhile).
Then CEL flashes again. My OBD2 reader confirmed a P0300 code which is a random misfire. But with 1400+ potential CEL codes...buy a $100 OBD2 reader to be sure. At the very least you'll be able to quote the code to your tech and they will tell you what it is.
Good luck!!

[MonsterEnergy]

Thanks Tubber273!

While moving the car this morning to get the other car out the driveway - it was juddering like crazy and "pffft" "pfffft" like it was misfiring.

Plugged in the OBDII reader and got the following faults:

P0431 Warm Up Catalyst Efficiency Below Threshold (Bank 2)
P0421 Warm Up Catalyst Efficiency Below Threshold (Bank 1)

These catalyst codes threw up the CEL some time ago and still seem to be kicking about - maybe catalyst on way out?

However, the new ones below came up - which agree with the misfire thing you mentioned Tubber273 and the flashing CEL.

P0300 Random/Multiple Cylinder Misfire Detected
P0305 Cylinder 5 Misfire Detected
P0306 Cylinder 6 Misfire Detected
P0307 Cylinder 7 Misfire Detected
P0308 Cylinder 8 Misfire Detected

So - multiple misfire on the right hand side of the engine. Any ideas what could cause that, please?

My thoughts are an electric fault or else maybe a dirty fuel filter going to that fuel rail.

In the meantime - I carried out a 30+ second battery reset and 10+ minute throttle reset. The CEL has stayed off after running for 20 minutes and the "pffft" "pffft" misfire and juddering engine sounds seem to have cleaned up a bit.

I wonder if it has just been a bad batch of fuel - and the engine has mapped itself to the bad fuel and the throttle reset will clear it and keep it running smoother and more responsive now? I hope...

I'm reluctant to take it to Maserati main dealer for this to be checked out - does anyone have any info on how to get into the fuel filters and where to change them?

If anyone can help - it'd be much appreciated.

Thanks

[Tubber273]

Hi Monster,

Sounds very close to my issues but I never had those catalyst codes. So far I've had to replace my O2 sensors, all coils, and both pre cats - plus a few other powertrain items!!
Don't read too much into that as I happen to be the PERFECT example of why you should always get a PPI.

Yes...I bought a lemon. Although it has been a significant cost, I'm pretty sure my 2002 has almost turned into a 2012. LOL

Back to your issue...I'd take it into the dealer as they have the proper diagnostic tools. I highly doubt you have my issues.Worst case is the cats, but more likely It could be the O2 sensors, MAF sensor, the coils, or what I might suggest is your problem...the catalyst temperature sensor. Heck...it could even be something as simple as spark plugs! To be safe and thorough, I highly suggest the dealership. They'll get to the bottom of it!

FYI....the costs of the various components (at least here) are: the O2 sensors - around $200, the coils are close to that ($200 X 8), and the worst case scenario is the cats are around $2500 each. Other sensors that could trip those codes include a solenoid valve variator control sensor ($350), and possibly a phase sensor ($250).

Keep us posted, and good luck! Hope it's a simple fix!!

[FlyinBrian]

I'm wondering if it could be the fuel rail? I believe they have a damper/regulator of some kind in them. Rich or lean conditions can both create misfires.

Was your engine running or idling rough before this (for a period of time) and it just got worse or was it more of a flick-of-the-switch transition?



I would definitely be tempted to get a proper diagnosis by a mechanic. Just starting to replace parts and seeing where it leads you can get expensive in a hurry.

[bkewc.taylor]

It does sound a lot like a misfire issue.

Please bear in mind that misfires under the wrong conditions can destroy all your catalytic converters in the blink of an eye. If the fuel and air went in the cylinder, and didn't burn there, then they're just waiting to burn when they enter the catalytic converter. If the cats are warmed up and they see this combustible mixture, they will overheat spectacularly after just a whiff or two of that mixture. If it happens, this is not a normal hot-exhaust problem: it is a combustion event (with temperatures to match, think ~ 1500 degrees F).

OEMs understand this problem (which was much more common on early-model cars equipped with catalysts, circa early-1908s.) They know it's serious; that's why CELs are sometimes programmed to blink when the engine thinks this is happening.

I suggest getting it to a dealer or mechanic ASAP; and advise never to let it misfire when hot.

Good luck...

[MonsterEnergy]

Originally Posted by FlyinBrian

I'm wondering if it could be the fuel rail? I believe they have a damper/regulator of some kind in them. Rich or lean conditions can both create misfires.

Was your engine running or idling rough before this (for a period of time) and it just got worse or was it more of a flick-of-the-switch transition?

I would definitely be tempted to get a proper diagnosis by a mechanic. Just starting to replace parts and seeing where it leads you can get expensive in a hurry.

The fuel rail is definitely getting fuel because fuel sprays when the bleed valve is pushed in.

I have it up at an Indy garage just now - they suspect an earthing problem. It seems to be running ok, if a bit rough, below 2500rpm, but as soon as you go above this is stutters and rumbles for a while but settles when the revs are dropped right back with no engine load.

The problem did kind of come on suddenly. And got worse pretty quick. I suspect it's maybe a sensor problem, maybe the O2 sensor on that side of the engine - but OBDII has thrown up no sensor error codes.

The Indy thinks an earth problem with a loose or worn wire that is only showing itself when the engine is under higher load - he says he saw a similar problem in a V8 BMW he once owned.

So none the wiser really - so if anyone has any brainwaves - please let me know - thanks.

Or if I was to start replacing sensors myself - what order would I follow for a diagnostic kind of resolution. Maserati main dealer is over 100 miles away, so would be big cost to trailer the car there, and their labour costs are crazy.

[MonsterEnergy]

Thanks all for your replies.

After going through diagnostic routes - checking coils, plugs, injectors - it was traced to the passenger side front cat being buggered. This was messing up the fuel/air mix and/or timing.

So got there in the end - with the help from you guys and some other forums - and car now running good again :-)

Thanks for input and time.