Two years of intermittent hard starts, please help!

[heinzboehmer]

Cool, thank you for the sanity check. That's what I figured, but, also what do I know ¯\_(ツ)_/¯ Definitely want to avoid replacing that unless I have strong probable cause, getting to those starter bolts is a bitch on jackstands.

The starter bolts aren't too bad from the front, as long as you have a flex head ratchet.

[ATB88]

Seems like the problem's getting worse. Failed to start on the first attempt for the first time today. Fired right up on second attempt. This was after coldstarting it (was a hard start), driving it a few blocks to pick up a large package, then getting back in the car to start again.

Any more suggestions? This is really driving me insane. With everything that I've replaced this engine should be firing up like new! Is ignition switch a possibility? Some other obscure electrical part?

It seems like fuel pressure is usually the culprit in these kinds of situations, but looking at everything that I've replaced, and the tests that I performed (see post on last page with videos), how could it be? Is there something I'm overlooking?? Willing to try/test anything!! Can also replace any part again because I have FCP warranty. Is it worth throwing another fuel pump at it???

Is there perhaps something I can log/monitor during a hard start that might give some clues?

If nobody has any more suggestions I might try and get Matt at Tech Craft to take a crack at it, as I've heard great things about him.

[oceansize]

I think you have hit that point where a fresh set of eyes might be best. I hate to read about these type of issues as I know how frustrating they can be.

[ATB88]

Called Matt, and we chatted about it. Really nice guy. He said that I've done everything that he would try, aside from replacing the fuel pump relay. I guess I'm gonna try it because it sounded like otherwise he's not sure either. Said he could take a look at it but would hate to charge me for just trying the things I've already done.

[Arith2]

What are your fuel trims? Do a compression test just to just bring you some ease. Who did your tune? Are you burning oil?

[ATB88]

What are your fuel trims? Do a compression test just to just bring you some ease. Who did your tune? Are you burning oil?

Arith2 : Tune is just stock CSL tune, currently running TMS airbox with MAP, euro headers and catless US sec 1. Before that I was just running a stock US tune with stock US airbox and stock catted headers. This problem existed with both setups.

Did a compression test a few weeks ago, 178-179 on cylinders 1,2,5,6. 172-173 on cylinders 3,4.

Car burns about a quart of oil every 2k-2.5k miles or so. Not brutal, not optimal. My understanding from discussions on the old forum were that some S54s just consume oil, some don't, and that this amount is not a concern. Is this correct?

I've been chasing issues with fuel trims since I bought the car 2 years ago. Back in stock configuration (before I did CSL airbox and headers) long term fuel trims were consistently high. 7-12% on bank 1, 5-9% on bank 2. Bank 1 ALWAYS 1-3% higher than bank 2. It was in pursuit of this problem that I replaced most of the parts that I did. More recently they'd been a bit better: 5%ish bank 2 and 7%ish bank 1, but that's still not great. I had quite an extensive thread about this on the old forum, but people didn't seem to think overall that this was a big deal. It still frustrates me. Post-CSL conversion fuel trims look better, but I'm still seeing elevated LTFTs on bank 1. Bank 1 will range -1 to +6%, bank 2 will range -2 to +3ish. I figure this is simply from the fact that the CSL tune tends to run rich on stock S54s, so, it's just shifting my problem down the spectrum. But whatever that problem is, it still seems to be there, as evidenced by the consistently higher trims on bank 1. The fuel trim issues existed long before the hard start issues. If they're being caused by the same problem it would be great to figure it out.

[ATB88]

Bit the bullet and shelled out for a new fuel pump relay (the last part of the entire fuel system that hasn't been replaced with a new part). No change.

I really just need this fixed, and it seems like it's outside of my ability and skill set given everything I've done at this point.

If anyone has a recommendation for a talented diagnostician in/near LA county please let me know! Hoping to find someone who is thorough and willing to consider and test unlikely causes once the obvious/common causes have been ruled out. Don't want to pay someone who's just going to say "oh, this is a normal problem I'm certain that it's your fuel pump. oh you replaced that? no idea then, sorry $120 pls." (have had this kind of thing happen a couple of times)

(Also still willing to tinker with things if anyone has new ideas/suggestions)

[eacmen]

Had similar issue to you. So over time i've learned to not just jump in the car and crank it. I would get in, turn the key to ACC for a few seconds then crank it over. This solved all my failed start issues. I realize this is not how it should be but I learned to live with it.

If you have already tried that then I am not sure what's going on.

My car would always start on second attempt as well.

[ATB88]

Had similar issue to you. So over time i've learned to not just jump in the car and crank it. I would get in, turn the key to ACC for a few seconds then crank it over. This solved all my failed start issues. I realize this is not how it should be but I learned to live with it.

If you have already tried that then I am not sure what's going on.

My car would always start on second attempt as well.

Thanks for chiming in! I actually did a few weeks of experimenting where I would either deliberately turn it to ACC for a few seconds before cranking, or just jump and and crank, and kept track of the behavior. I seemed to have the same number of hard/bad starts in either case :/

In your case, it *sounds* like a fuel pressure problem because leaving the key at ACC for a few seconds gives fuel pressure time to build up. But I would guess you've already gone down that road? These mystery issues are the pits :/

[M3_CJ]

ATB88 sorry you have so much trouble. You are not alone, I'm too been having these rough start symptoms for the past 1.5 years since 54k miles on the car (currently at 63k) and have not done much to seriously try to fix the problem.

My symptoms: Varying chance of normal starts and long 'hard' starts with sometimes having to crank the 2nd time (always smooth start on 2nd try). I have been doing Eacmen's advice to turn Key to ACC for few seconds (usually put my seatbelt on at this time) and crank it, but still same issues where its just random if it wants to act up or not (50-60% chances). No mods on car other than coilovers and a section 3 exhaust. Everything else seems fine once the car is up and going.

So far I have only done light work: spark plugs + coils + fuel filter (also from FCP as I mostly source from). I had the VANOs rebuilt + valve adjustment, but even before this work the hard start was acting up although not as much as currently.

I was thinking of doing the fuel pump as next step but at $495 a piece, I'm thinking of finding a shop that could do a fuel pressure test first before going the route of the fuel pump (still need to find a good reputable shop close to my area)

I'll be following this post and I can update after I try each possible solution (i'm probably going to go off the list you completed already, anything would help at this point).

Hope you'll find a solution to yours!

[ATB88]

ATB88 sorry you have so much trouble. You are not alone, I'm too been having these rough start symptoms for the past 1.5 years since 54k miles on the car (currently at 63k) and have not done much to seriously try to fix the problem.

My symptoms: Varying chance of normal starts and long 'hard' starts with sometimes having to crank the 2nd time (always smooth start on 2nd try). I have been doing Eacmen's advice to turn Key to ACC for few seconds (usually put my seatbelt on at this time) and crank it, but still same issues where its just random if it wants to act up or not (50-60% chances). No mods on car other than coilovers and a section 3 exhaust. Everything else seems fine once the car is up and going.

So far I have only done light work: spark plugs + coils + fuel filter (also from FCP as I mostly source from). I had the VANOs rebuilt + valve adjustment, but even before this work the hard start was acting up although not as much as currently.

I was thinking of doing the fuel pump as next step but at $495 a piece, I'm thinking of finding a shop that could do a fuel pressure test first before going the route of the fuel pump (still need to find a good reputable shop close to my area)

I'll be following this post and I can update after I try each possible solution (i'm probably going to go off the list you completed already, anything would help at this point).

Hope you'll find a solution to yours!

Cool glad to know I'm not alone! Yeah I was pretty disappointed when throwing $500 at a fuel pump didn't solve my problem. I'm pushing 75k, so, the fuel pump was going to be due soon-ish anyway, so that makes it easier to swallow. I've heard lots of stories about them dying between 75k-100k leaving people stranded, so, it's not a terrible idea to replace it preventatively. Just expensive.

I'd say before spending any money have fuel pressure tested by a mechanic (or do it yourself if you're set up). That's where I started. Hopefully I find my gremlin and it helps you find yours before you spend so much!

Question: any way this could be battery/starter/alternator related? Battery is 2 years old, alt/starter are most likely original. Any definitive tests I can do for the health of these items?

[ATB88]

Update: took it to TechCraft today and Matt checked it out. Everything looked good to him, and he said the only other thing that he would consider trying is a cylinder leakdown test, just to see if somehow something got effed up when I did the timing work that coincided with the start of this problem. He was hesitant to suggest it because he didn't think he'd find anything, due to compression being solid, but it was his only idea. There was a point during my timing work that I accidentally was turning the crank (by hand of course) without the cams attached to the timing chain, and I met valve on piston resistance. So, it didn't seem completely out of the question that maybe I had bent a valve or something when this happened. Feeling desperate I approved, so, he did it, and all 6 cylinders came out perfect, <2%. He said it was one of the healthiest seeming S54s he's seen/worked on.

Unless anyone has any other suggestions, here's the last thing I'm going to try: I'm going to take the valve cover off one more time and very carefully re-time the engine again as well as check the valves. It was exactly after I did a re-time and valve adjustment back in October that this issue started. So, I'm going to re-trace my steps, re-do everything, and hope for a miracle that I find something (maybe valves out of spec somehow, a snickers bar wrapper, or a used condom wrapped around a cam lobe, I'd be thrilled to find anything that explains what's going on) or perhaps that the act of re-doing everything mysteriously fixes the problem (just as mysteriously as it seemingly caused it). If this fails, f*** it, I'm selling the car. Or pushing it into the ocean, depends how I'm feeling after.

[mmobmw]

I suggest replacing the starter motor. I had a similar issue at 74k miles. On/off hard/sluggish starts, then one day it wouldn’t start. I thought it was the battery but nothing changed after I replaced it (just one click, no start). So I changed the starter motor and it starts like new. It was a pain but I followed the shoplife video https://youtu.be/t6whLYwm4iE including the harbor freight tool. Good luck!

[ATB88]

I suggest replacing the starter motor. I had a similar issue at 74k miles. On/off hard/sluggish starts, then one day it wouldn’t start. I thought it was the battery but nothing changed after I replaced it (just one click, no start). So I changed the starter motor and it starts like new. It was a pain but I followed the shoplife video https://youtu.be/t6whLYwm4iE including the harbor freight tool. Good luck!

This is interesting, and possibly promising.

May I ask, did your hard/sluggish starts sound like mine do in the youtube videos I posted on the previous page? A couple of people have told me it doesn't sound like a starter problem, but, if yours sounded similar in behavior before your starter completely gave up then I'd be definitely be willing to look into the starter! $160 for a valeo unit from FCP... not tooo bad

[exodus454]

Just out of curiosity have you gotten a smoke test done? It's possible there's a leak somewhere that's throwing things off on the intake or exhaust side.
If the CSL software runs rich out of the box I'd expect to see negative fuel trims.

If you reset all the adaptations does the problem still occur?

If you look at the air/water/oil temps when the car cold, do they all match ambient temps? Does the baro and MAP match ambient? What's your RF at idle?