very rough first start of day - check engine light - P0306 - questionable dealer response

[Kraig Wilkinson]

So an update on the permanent code of P0304. I mentioned earlier I cleared the verified code but the perm did not clear. I put in some Liqui Moly injector cleaner with appr 7 gals left in tank. Ran that out a refilled with Shell 93. Car is def running smoother and CEL has not come back on. For sag I checked codes and the permanent P0304 code is gone.

Liquid Moly! I am going to try that stuff. It would be nice if all problems were that easy of a fix.

 

[G-266329]

Well don't know that it's fixed but it's better for sure. It's called Liqui Molly. $8 bucks. Found a 6 pack on Amazon for $32.

 

[mth]

Dont know that its fixed but its better at the moment. Stuff is called Liqui Moly. $8 a can. Found a 6 pack on Amazon for $32. I am baffled by the fact the permanent code cleared.

 

[Kraig Wilkinson]

Dont know that its fixed but its better at the moment. Stuff is called Liqui Moly. $8 a can. Found a 6 pack on Amazon for $32. I am baffled by the fact the permanent code cleared.

The injectors are happy now and firing off the way they should and told the computer . So code was cleared??? When I first bu ougbt my 5.0 it ran really crappy, even after the 600 mile ride back from dealer. I thought what did I just buy! So I started running injector cleaner and do so almost every time ai fill up and now you cant even feel it idle. I am going to give that moly a try!! Thanks for the info!!@

 

[inmanlanier]

I too am baffled, however this is excellent feedback.

You have given me enough information to conclude that GDI is the ultimate challenge - these injectors (IMHO) tend to hang up in the open position (at least in my experience and I think yours). I will look at my records and schedule the occasional Techron bottle to the tank.

Thanks to all of you with feedback. These forums are great. If only they had been around 40 years ago!

 

[Kraig Wilkinson]

I too am baffled, however this is excellent feedback.

You have given me enough information to conclude that GDI is the ultimate challenge - these injectors (IMHO) tend to hang up in the open position (at least in my experience and I think yours). I will look at my records and schedule the occasional Techron bottle to the tank.

Thanks to all of you with feedback. These forums are great. If only they had been around 40 years ago!

These forums are great I learned alot about the electronics of the Genesis from this forum! I agree about the 40years ago it would have helped me out big time.

 

[Whitey]

I too am baffled, however this is excellent feedback.

You have given me enough information to conclude that GDI is the ultimate challenge - these injectors (IMHO) tend to hang up in the open position (at least in my experience and I think yours). I will look at my records and schedule the occasional Techron bottle to the tank.

Thanks to all of you with feedback. These forums are great. If only they had been around 40 years ago!

Exactly Inman! It's simply great to have a forum where we can share our respective love for our cars and where everyone seems to take a true interest in helping one another, a rare treat these days.

 

[inmanlanier]

Hopefully a final update. Not long after getting the car back from the dealer (running well), we needed to drop it off at a body shop 20 miles away for some front bumper repair. By that time the Techron had not been in but maybe 30 miles. On the way I asked my wife to follow me as I made some full throttle pulls. From the beginning she noted a good bit more smoke coming out of the left pipe (confirming that the #6 injector was still not totally healed). I noted the data point.

Yesterday (perhaps we're now one more tank later?) - we needed to drop it off at Hyundai for the trunk opening button in the back - rubber cover had failed. This time I followed her - limited smoke initially - both pipes the same amount. It appears the Techron did the trick.

On a related note, I also have an F type R Jag, there is a post there where folks have similar issues with injectors getting stuck open (I believe it's also a direct injection motor). They occur on those engines (5.0L Jaguar AJ-V8 design (not Ford), supercharged - 550 HP) as low as 30K miles. So... welcome to the world of direct injection. I hope the gas formulators are going to take note and refine the blends to make the normal additive packages handle this. If not, another efficiency gain at some cost to reliability.

 

[Whitey]

Good to hear, Inman. Mine's running well but I've noticed a slightly noisy idle of late. Will be taking a run down the coast tonight to Naples, so filled her with Shell Nitro and Techron this morn and hope to blow her out a little and see if it quiets her down.

And nice on that F-Type R, one of my more fav cars on the road these days. Thought about one but have been down the Jag road back in the day and had an XJS V12 Coupe, which was without a doubt one of the best driving cars I've ever owned, but that British reliability left much to be desired. It ran great, that is when it ran, lol. I know they're a very different car today, but I tend to want something I haven't had yet, hence the Genny.

Side note: I'm pressing forward with my attorney on Napleton as he feels they've violated a certain Florida Statute. I mentioned that others have had bad experiences with their dealerships in that area, and he asked me to provide a copy of the forum thread for additional support. Felt I should ask if you have any objection with me providing this to him? Just let me know if you do, thanks!

 

[inmanlanier]

Not at all a problem regarding giving my information. If you need further dialogue, you can PM me. As an FYI, I'm not just a casual gearhead, I have quite a bit of experience in automotive - including building a Cobra Replica, custom designing brake systems, etc. In other words, likely a more credible source to your counsel vs. a normal lay person. I say that with humility in mind.

This is timely because yesterday I spoke with the service adviser I normally deal with (she was not in the day I had the 'water in fuel' issue). I offered to educate her young 'master mechanic' on the unlikelihood of, and real indications of water in fuel. She did affirm they've had that before. I stated not in my instance. She was very politely non-committal about my chatting with the service tech; she stated she was glad it was resolved.

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[Whitey]

Not at all a problem regarding giving my information. If you need further dialogue, you can PM me. As an FYI, I'm not just a casual gearhead, I have quite a bit of experience in automotive - including building a Cobra Replica, custom designing brake systems, etc. In other words, likely a more credible source to your counsel vs. a normal lay person. I say that with humility in mind.

This is timely because yesterday I spoke with the service adviser I normally deal with (she was not in the day I had the 'water in fuel' issue). I offered to educate her young 'master mechanic' on the unlikelihood of, and real indications of water in fuel. She did affirm they've had that before. I stated not in my instance. She was very politely non-committal about my chatting with the service tech; she stated she was glad it was resolved.

Thank you, Inman. Yes, I gathered from your prior posts that you have far more knowledge than I will ever have. I simply love nice cars and know enough to be dangerous, lol. Yourself and others out here are the ones that help teach guys like me. So I agree your words carry more weight and this will surely be helpful. As this gets further along, I may very well reach out via PM. I hope to teach them a lesson down there.

I just love when a so-called "expert" gets schooled by one who truly is.

 

[ntmehan]

I've got a more in depth post about this that you can find if you want the more in-depth read but I think my car had a similar issue before I purchased it. LSS: I purchased my 15 5.0 Ultimate in July with 47k miles and found out that the engine had been replaced under warranty at about 42k miles. The initial problem was a rough idle and misfire on Cyl 8. The dealer (in STL area) replaced plugs, injectors, coil packs, injector harness, injector driver, ecu, short block (and associated kit internals), and finally heads (and associated kit internals) before the misfire on the same cylinder was finally resolved. They believed bottom end damage could have been caused from a stuck injector washing down the oil film as previously mentioned which is what prompted the short block replacement. Apparently these injectors aren't the greatest. Not sure why the final fix of swapping new heads ended up fixing the problem though, but I'm glad they did it (HMA wanted to just warranty replace the head on the bank where the misfire was occurring and the original owner fought them to replace both since they had had the car for 6 weeks and had already replaced everything else. They agreed.) since that means my 5.0 is essentially a new engine from the manifolds inward. I've been running just top tier gas (Shell, thanks T-Mobile Tuesdays!) in mine (be it midgrade or premium) to hopefully mitigate any deposit issues. I wonder if those of you that have had this issue intermittently just caught it early enough and cleaned up your fuel system so it didn't progress to what mine did. It's buttery smooth now, I'm really missing it while it's in the shop and I'm driving a G80 loaner with a 3.8 (which is sort of gravelly...)

 

[inmanlanier]

Thanks ntmehan - yes I've read other posts regarding stuck injectors. I also remember reading one where the amount of fuel injected after shut down and subsequent startup hydraulically locked the block! For this reason I'm concerned. We also had a 2014 Sorento that purportedly had some issues with injectors (earlier GDI) - I had to put Techron in it from time to time.

In addition to putting in Techron preventively from now on, I'm likely to do some full throttle tests whenever we have a follower as an added check.

 

[Markymark]

Don't forget to do periodic Italian tuneups too.

 

[inmanlanier]

I tend to do that a lot more often in my F-type

 

[Markymark]

So I took out my 2015 5.0 in cool weather (50 °F) yesterday, drove about a mile and a half and then saw a BMW M4 who was giving me some attitude. From the stoplight, I accelerated normally to about 15 mph, then gave her the beans. Car took off great, but at about 50 mph I noticed my CEL was flashing rapidly. Fvck!

The CEL went off after about 15 seconds and stayed off. So I put the cheap code reader on it and I have a P0305 and a P0303 and a P0300. I generally put 93 octane into it, and have put in a bottle of Techron in the last 2000 miles.

You guys think I should wait until the engine's fully warmed up to give it full throttle? I didn't notice or feel any misfiring, or see any smoke. Car has 75,000 miles.

 

[EdP]

So I took out my 2015 5.0 in cool weather (50 °F) yesterday, drove about a mile and a half and then saw a BMW M4 who was giving me some attitude. From the stoplight, I accelerated normally to about 15 mph, then gave her the beans. Car took off great, but at about 50 mph I noticed my CEL was flashing rapidly. Fvck!

The CEL went off after about 15 seconds and stayed off. So I put the cheap code reader on it and I have a P0305 and a P0303 and a P0300. I generally put 93 octane into it, and have put in a bottle of Techron in the last 2000 miles.

You guys think I should wait until the engine's fully warmed up to give it full throttle? I didn't notice or feel any misfiring, or see any smoke. Car has 75,000 miles.

I'd get it warmed up well and do it again. Being cold it may have been a rich mixture and less than perfect combustion. Possible you have a plug or coil that is marginal too, thus the trial when properly warmed.

Now, I'm not being critical of you because I may have done the same under the circumstance, but I never get hard into it that cold.

 

[Kraig Wilkinson]

I'd get it warmed up well and do it again. Being cold it may have been a rich mixture and less than perfect combustion. Possible you have a plug or coil that is marginal too, thus the trial when properly warmed.

Now, I'm not being critical of you because I may have done the same under the circumstance, but I never get hard into it that cold.

Yes I agree with EdP. Operating temp is the best time to give it the beans, I usually wait a good half hour to hour before I lay into to it hard. I guess also depends on what the outside temp is? I think about how warm the trans fluid is also. The forgotten fluid!!

 

[Markymark]

Yes I agree with EdP. Operating temp is the best time to give it the beans, I usually wait a good half hour to hour before I lay into to it hard. I guess also depends on what the outside temp is? I think about how warm the trans fluid is also. The forgotten fluid!!

Thanks gents. Sometimes the prey instinct just kicks in, you know? I like to eat BMWs for lunch. It can't hurt to chuck in a bottle of treatment. (I never have felt any kind of hesitation or misfire yet.)