Starting when Hot

[shadowpuck]

Just curious - I've had sporadic problems with starting my '03 zhp when the outside temperatures are very warm; say 90 degrees or warmer.

the scenario is this: car will sit all day, ambient temps will be quiite warm. i'll key the ignition, all lights, electric, etc. all work. push in clutch and no start, no crank, nothing. all lights and electrics still work. shut everything off, wait a second, and all is good. sometimes it takes more than one try.

one thing i need to try is swapping keys to see if i have a transponder issue of some sort.

problem only occurs in high ambient temps - never had it happen first thing in the morning or when temps are cooler.

i thought about the clutch switch, but as i understand it production after 03/2001 use a different style (magnetic) and thus is less likely to fail.

so, anyone have any experience with this?

[Johnmadd]

Sounds like a bad starter to me. Next time it happens have a friend try to start it while you tap on the starter with a wrench or something. My e30 does this right now.

[shadowpuck]

that's certainly a possibility, and i've added it to the list.

as we've had nothing but high ambient temps lately i had ample oportunity to test. tried my other key and had the same problem, so i don't think its anything along those lines.

gonna be a tough one to test, though, as the typical situation is:
get in car to leave work
high temps 95+
try to start car - all electrics work but no crank, nothing from engine
shut everything off, wait a second, do it again and it works totally fine

[shadowpuck]

well, just to provide an update.

i tried replacing the main relay in the relay box in the engine bay.
the part was cheap and easily accessed. had found some notes from others that had problems with this part.

it seemed to work yesterday, but today, with ambient temps above 105, had the same issue.
first try, all electrics and everything else working fine. turn the key to start and nothing happens.
shut everything off, wait a second, try again and all was well. car starts right up.

so, seems like the possibilities are:
something with the EWS/starter disable system/ignition switch
something with the clutch "switch," as it exists on this model
something with the starter - as suggested above

i've duplicated the problem with both keys.
this only occurs in high ambient temps (mid-upper 90's and above)
seems more likely if the car has sat out in direct sun for many hours.

[MrMaico]

Ignition/EWS is the first thing that came to mind for me. Unfortunately, I don't know of any easy way to test/troubleshoot. BMW had a LOT of trouble one year with faulty EWS antennas on their bikes. Finally after 3 "new and improved" versions of the antennas they got the problem fixed. Lots of pissed off owners of brand new bikes that suddenly wouldn't start.

[Mtnman]

i was thinking it had to do with the clutch, especially if it doesnt make any noise when you go to crank it. But just my first thought, and no good diagnostics to go with it.

[MrMaico]

i was thinking it had to do with the clutch, especially if it doesnt make any noise when you go to crank it. But just my first thought, and no good diagnostics to go with it.

That could certainly be a possibility too. I'm guessing if you have a modified clutch stop that you've already tried adjusting it lower? Intermittent electrical issues can be the worst to figure out. At least it's not leaving you stranded......so far.

[shadowpuck]

no clutch stop for me. and, the clutch switch, as it were, on this model appears to be a different variety than the typical clutch switch. i will do some more research on that area.
i agree, it seems like something along the lines of either EWS or clutch switch. it only happens, at least now, in those high ambient temps.

something isn't allowing the signal to start when i have the problem - no crank, nothing; however, nothing electrical stops or acts like there's too much draw or something like that. which is making me think it's something switch or signal communication related (ie, EWS).

[shadowpuck]

long overdue update.

the problem has now morphed into a more traditional non-start issue.

a few weeks ago, started the car and it made a funny grind/scrape sound right as the motor turned over.
immediately afterward, began having random problems in all temps getting the car to start. sometimes it cranks on first try, sometimes it cranks after a few tries. today, it took 20 minutes of trying to get the car to start.

at this point i'm planning on replacing the starter and the ignition switch. since i have 130k on the car, been thinking of attacking this from above by removing the intake as that would be a prime opportunity to replace the ccv/oil separator and check out vacuum lines, etc. i know i don't need to remove the intake manifold to do these jobs, but since the car is going to sit for a bit and i can drive something else seems to make sense and make the job a bit easier.

still need to hook up my computer and see if i can see anything code related stored...

so, i've read several writeups on various forums, including here, regarding starter replacement. anyone that did it removing the intake manifold? if so, did you find that it really helped to do the job? i've removed an intake on an e34 and an e36.....

also, thoughts on my parts replacement plan? am i nuts??