'91 M42 long start... really long crank.

[ck_taft325is]

My recent M42 has been having a hard time starting. Almost as if it doesn't want to at all. Once started it idles fine, a tad low but holds steady. Now, while driving for the first time of any given day (hot or cold) in 2nd gear at about 2,600rpm it'll want to stall and nearly die. If you get into third gear and drop the rpm's it's fine or above 2,600rpm in 2nd.

The real issue is the ridiculously long crank to get it to turn over. To give an idea, my last M42 powered car took let's say 5 cranks to fire up. This car takes a good solid 12-15.

Any suggestions? Going to clean the AFM out a bit this next weekend and poke around a little. The mess under the intake was resolved by the PO but, the TB heater plate is still connected. Not sure if this does or would even affect anything.

[KenC]

Man. That sounds weird.

My first guesses would be ECU or FPR.


The stall @ 2600 is only the first time you drive it?

[rjcaptsean]

Sounds like it could be the FPR or fuel pump. Perhaps the pressure isn't staying in the fuel rails and it has to reprime to get fuel flowing. By the way, when is the last time you changed out your fuel filter?

[Dj Buttchug]

gonna say fpr as well...

[harv]

How old is the fuel filter?

Check to see if the throttle body is clean.

John

[blalor]

I don't have the stalling problem, but mine does take forever to start, especially when it's cool or cold. When it's warm, it'll usually fire right away, but during the winter it'll crank for 5-10 seconds (perhaps longer) before catching and then I'll have to continue to spin the starter to give it enough momentum. It's never failed to start, but it sure needs a kick in the ass to get going sometimes. Fuel pressure has been suggested to me, as well, but I've balked at buying the $60 fuel pressure regulator until I can test the whole system.

[ck_taft325is]

I'll check into the FPR ASAP. That actually makes sense.

As for the fuel pump, I'm not positive. Nor the fuel filter. I'll check both of those as well.

The FPR might be telling though. The car sat for almost a year and a half. It's been gone through by our local detailing guru, John Parker as that's who I bought it from. Runs strong as hell once it's warm. Although, I'm not entirely used to having a working fan and corresponding fan shroud ;) Makes it sound like a wind tunnel up front.

[ck_taft325is]

Barely starting at this point. Fuel filter looks fairly clean. FP is pumping gas just fine. Not sure why it's refusing to start. It's juuust barely starting after a good solid 15-20 seconds crank.

[Balleristic31]

Mine is starting to do this exact thing. Takes WAY too long to start. And about a week ago it would start on half a crank.

[bmwm42]

check the sensors cps

[StereoInstaller1]

Man, we have got to build a test stand for injectors.

You let an injector sit with 60PSI on it for 2 minutes, you will know if the thing dribbles.

[Balleristic31]

Its def not the injectors (at least for me) because when I turn the car to the on position and let pressure build in the rail, it starts normally. I really think its the FPR

[ck_taft325is]

Get this... it was the battery. Still a bit of a crank but, the rpm and idle are solved. Crank is tolerable.