Bomar Shelby

Sweet Jesus, I hope I'm not on this track. Just had 80K maintenance done on my 2009 C4S which was misfiring intermittently prior to going in the shop.Indy called this evening to say work has been completed but new plugs and coils did not fix misfire. Still misfiring cold and when warm. They will hook up PIWIS and drive it tomorrow, stay tuned

808Bill

Imo000

Find someone that knows what they are doing. These guys are just throwing parts at it and making you pay.

808Bill

Shawn's motor grenade shortly after all this...I hope your indy knows what they are doing!

Bomar Shelby

yeah, they just called and said I need to authorize another 4 hours for further diagnostics at $140/ hr. Cylinders 1 and 3 showing misfire, cylinder 2 showing fuel injector fault upper limit exceeded , faults for O2 sensors both banks. Now doing PIWIS drive around diagnostics versus just pulling codes. Next up, visual inspection of electrical connections in engine bay. Followed by smoke test looking for vacuum leak and if negative mass air flow sensor will be under suspicion. Prayers welcome, stay tuned.

Mike Murphy

I went through many hours and authorizations on my last repair. It’s actually not a bad sign, if they are intent on finding the actual issue, rather than guessing.

FlyingShawn

So so sorry to hear this!!!

I never had O2 codes, but those sound vaguely familiar as possibly pointing to the MAF based on what I recall from the research I did during my misfire ordeal. Regardless, I can't overemphasize thoroughness when checking the electrical connectors and engine grounds: the bad grounds at the source of my trouble were clear on the other side of the engine from where the codes were pointing! If it's not either of those, I genuinely hope that some of the ideas/research that happened in this thread can help point you in the right direction. Good luck and keep us updated!

P.S. Quick update since I know I've gone dark lately: my indy shop has been so backed up on problem cars (particularly an old Lotus that's required a significant amount of re-wiring) that they still haven't completed the simple diagnostics that I've been waiting on such as dropping the sump. I've run the math a dozen different ways and the numbers are in favor of a rebuild verses just dumping the car as a roller, but I'm waiting to talk to Jake/RND/EBS/etc until that work is done and I can tell them with more confidence the current state of my engine.

Mike Murphy

Based on the above, you might not get a slice of time until the year 2035, lol.

Flat6 Innovations

The first thing that needs to be done is checking for bore scoring. This must be done on both sides of the bore, like my part 4 in the bore scoring video series illustrates.

Then you need to decide how much you are in LOVE with the car. If anything other than love determines the path, there's no need to call me.

FlyingShawn

If I've already resolved not to consider any rebuild option that doesn't include Nickies, does the current level of bore scoring (believed to be little-to-none) even matter since that material would be removed anyway?

Unfortunately 12 days of driving isn't enough to know either way on the love question , so I'm forced to choose an option using other means. I know I'm not considering any options that don't give me an engine I can confidently drive well into the future, so I'd be remiss if my decision process didn't include at least a relatively brief chat with you (maybe 20min compared to the usual hour? Basically just long enough to ask a few questions not answered by your website, learn about the latest pricing, and about the current wait list length).

Flat6 Innovations

I can answer these here.

Our first available completion of an engine for the "Premier Service" (using our most local to you Certified Installer to remove, and replace the engine) is currently October 2020. These engines come fully dyno tested, from our engine dyno.
For the "Exclusive Service" (where we collect the car for the full process here) the first available completion is currently March 2021

Of course, pricing matters a lot based on the actual failure that you are experiencing, unless you do have bore scoring. If you do, and the damage is limited to this, with no collateral damages, the pricing starts at 20K for a Stage 1(Premier Service), and goes up steeply from there when someone selects the "Exclusive Service".

Of course, we can schedule a chat, but the timeline is usually enough to make the decision for most people to go some other route. I have NO desire to reduce wait times, increase volumes, or make my hand crafted engine, built by a single human from start to finishing something "generic", or easy to get.

Bomar Shelby

Ok, now after three full work days with no contact (well I called for update yesterday morning and the person who answered the phone said he had just arrived and didn't know status of my car but would check and call back but failed to do so). I called this morning for an update . I was told they think they found the problem to be a faulty valve lift solenoid and verified by putting in a known good part and no misfire codes appeared . Recommended replacement of faulty valve lift solenoid $220 for part , also said they are usually replaced in pairs (Now $440) (one for each bank) because the Labor involved is 2.5 hours and if the second original solenoid fails I would be looking at another 2.5 hrs labor. So I told them to go ahead and replace both. Of course they can't guarantee they will cure misfire until installed and car test driven at least 20 miles. Oh yeah, they said the 4 hrs of additional diagnostic I had authorized were exhausted. No mention of whether smoke test for vacuum leaks was ever performed.
Now I confess I don't read every forum post regarding mysterious misfires but I've never heard anyone else say , "oh yeah it was the valve lift solenoid" . Anyone else had that issue?

808Bill

Can't say that I have but time will tell, do keep us posted. Maybe start a new thread with your issues.

Flat6 Innovations

The valve lift solenoid will create a set of misfire codes for one whole bank of the engine simultaneously. You will have P0300 with a P0301,0302,303 or a P0300 with P0304,305,306 together.

Anything is possible. What codes did you have?

Rdrcr

Great suggestion. Much agreed.
I too suggest starting fresh including previous posts to start a new thread with these issues...

Mike