Hi all,
I'm looking at a 2013 500 for a friend of a friend, a 1.2 pop from what I can gather.
The story so far: The owner says it's running terrible and can smell petrol in the cabin. It's been to two garages, one replaced plugs the second replaced the coil pack (without any testing of course}. It has also had the battery changed from a stop/start to a standard and the owner was told to disable the stop/start.
I've only had a quick look and scan the other night. I got a P0300 ignition failures recognition - intermittent. A STFT fluctuating between +6%.....+28% and a LTFT of -86.2% Under the hood I removed a very loose fitting air box and found the rear bushing support was broken off and a broken connector for a vacuum line which lead down to under the throttle body/intake manifold, idle control maybe??
I'll be getting back to the car in a day or two to test everything so just wanted to ask you folks before I go taking it to bits for any advice, tips, techniques, known issues etc.
Any info greatly appreciated.
Tommy

Plus I'll post back with my findings and throw in pics to maybe help others to.

TommyLT said:

a broken connector for a vacuum line which lead down to under the throttle body/intake manifold, idle control maybe??

Click to expand...

If this is the pipe from the lower right side of the throttle body to the underside of the air box, it's just a breather pipe for the TB, not a vacuum pipe.

It's easy to break if someone is hamfisted, the barb under the airbox the other end fits is very brittle, so it's best to pull it off at the TB rather than the airbox.

I broke mine the first time I removed the airbox (yeah, I'm hamfisted) and I've just left it loose since without issue, it's meant to suck the fumes back into the engine, it does need sorting, one day.

P0300 is a general misfire code, the odd fuel trims I suspect are a result of the misfire due to ignition.
As it's not specific to one cylinder (last digit in the code is 0, not 1, 2, 3 or 4 which would identify a cylinder) it may be due to a connection issue to the coil pack causing all to misfire (what do the plugs look like, all the same colour?), it's not unheard of for the connector/wires from the ECU to break down or fail.

Though don't rule out the O2 sensor, I had issues with the heater circuit on an upstream one.
It failed to pre heat properly which caused the PCM to revert to a safe fuel strategy of Open Loop - System Fault (very rich) and misfire badly with P0300.
Oddly it threw no O2 codes, but once the O2 was hot, the car restarted and ran fine until it cooled again.

It's possible to repair the spigot and I would replace the hose as it gets brittle

An ill fitting or broken/split breather hose will create a smell of fuel in the cabin.

Thanks for all the replies

I found the cause of the misfire, checked compression and got 16 bar on all cylinders.Coils, leads and sparks all checked out however no.4 looked a little burnt.Whipped the injectors out, all looked ok and the resistance checked out. Gave them a live fire and no.4 was firing intermittently. I swapped it over to no.1 and it gave up completely. ECP were after £130ish for a new injector so I went the cheap route and got two new ones from ebay (the last two)£10 each. Fitted the new injector and crossed my fingers, she's now running sweet.

Thanks for the tips and advice.

Tommy

I tried to post a link to a vid of the injector testing but unfortunately I've not made enough posts to do so, sorry folks.

TommyLT said:

I tried to post a link to a vid of the injector testing but unfortunately I've not made enough posts to do so, sorry folks.

Click to expand...

I’d like to see this injector testing - sounds interesting! Specifically I’d like to know how to give them a “live fire” without actually having a live fire, as it were.

-Alex

Just tried to post the link again.... say's I need a post count of at least five.

Post no.4!

Post no.5!

Here's the live fire.....crossing your fingers should prevent any real live fire!
[ame]https://vimeo.com/283559682[/ame]