Miss, no start, fuel smell

[Silversteed]

Installed DOB supercharger and was working on the tune. The last 150 miles it was running great! Then a couple of days later it was hard starting and once it started there was a miss. Car still drove well and was fine accelerating.

Some times it starts and some times I have to pump the throttle to get it started. Once warm it is pretty good

It has new fuel injectors, fuel pressure sensor, fuel pump, plugs, throttle positioning sensor. Vacuum is approximately 20 psi, fuel pressure is good. I've had P0356 for cylinder 6 as well as one time having it for all cylinders. Moved the coils and it didn't follow.

I am not sure where to look next. Any ideas?

Thanks for the help

 

[DieHarder]

Because parts are new doesn't mean they're working perfectly. Try replacing COP #6 with an old coil and retest. It's often the case that the end of the coil gets pushed up into the boot and causes intermittent performance. If problems persist it may be the the wiring to COP #6 or the fuel injector. If neither suggest having a dealer run a diagnostic on it to help narrow down the problem even though it'll cost ~$200. Has been money well spent a couple of times in my experience vs continually firing the parts canon.

Also, check out the FPDM relay modification (that was part of the upgrades you should have made) in the trunk. Mine had the cover knocked off by the plastic panels in the trunk which caused it to act erratically and manifested symptoms similar to yours. The unknown in your case is the fuel pump. You should hear it prime whenever you turn the key to 'On' (even with the engine off). If not, need to determine why.

Regarding the tune. Who''s doing your's? Highly recommend Lito though you'll need to install a Wideband sensor. Only took three iterations for mine. Been running great ever since.

 

[Juice]

New supercharger, + working on tune + engine starts to run bad after a few miles. Let me think, maybe a compression test should be the next step. I have a feeling its hurt.

 

[Laga]

In the past year, I have bought brand new faulty COPs and throttle position sensors. Electronic QC is bad nowadays. Also, check your wiring moving things around with a major upgrade can cause a short, especially when the things get hot and move around.

 

[Silversteed]

Because parts are new doesn't mean they're working perfectly. Try replacing COP #6 with an old coil and retest. It's often the case that the end of the coil gets pushed up into the boot and causes intermittent performance. If problems persist it may be the the wiring to COP #6 or the fuel injector. If neither suggest having a dealer run a diagnostic on it to help narrow down the problem even though it'll cost ~$200. Has been money well spent a couple of times in my experience vs continually firing the parts canon.

Also, check out the FPDM relay modification (that was part of the upgrades you should have made) in the trunk. Mine had the cover knocked off by the plastic panels in the trunk which caused it to act erratically and manifested symptoms similar to yours. The unknown in your case is the fuel pump. You should hear it prime whenever you turn the key to 'On' (even with the engine off). If not, need to determine why.

Regarding the tune. Who''s doing your's? Highly recommend Lito though you'll need to install a Wideband sensor. Only took three iterations for mine. Been running great ever since.

I'm going to try a new Coil as I don't have a new one. I have played around with the wiring while it is running and there isn't any noticeable difference. I'm also going to check FPDM as I can see how it could get knocked around.

I do hear the pump prime every time I turn the key on. Also, I have a boost gauge and a wideband. The boost is approximately 19 when at idle and the wideband swings from 14.7 down to 11 and then it goes up past the top number, I think 18 then it displays dashes. I haven't had it over 5000 rpms and it has never knocked. Basically 3k to 5k pulls. Thanks for the help.

 

[07 Boss]

Well it's obvious you have some kind of fueling issue if your A/F gauge fluctuates that much at idle. It should stay pretty constant. Should be stoic at idle, 14.7-14.9. Only on a cold start it might run a little rich until she starts to heat up.

 

[Juice]

Confirm the stock O2 reads same as wideband. Idle tuning I always go by the stock upstream sensor. WB is for WOT.
A dead cylinder will show up as 'stuck lean' (18+ on the WB)