Car stalled on off ramp 1990 535i

[ahlem]

My 421,000 mile 535i 5 speed sat for about a month as I was getting some road time on the 1989 325is after a rear end bushing and seal refresh.
First day back on the road I got 2 miles from home and hit the on ramp. Stutter, stutter.
I feather footed it and got it up to freeway speed but it seemed like it was running on 4 then 5 cylinders.
About 2 miles to the exit and it died when the rpm's dropped at the stop light on the off ramp.
AAA to the rescue. I was able to start it in the drive way once it cooled down. After idling a while and revving a bit it started to miss as it warmed up.
My plan is to check the suspect cap and rotor since they are pretty old. Checking the fuel pressure is sort of a PITA but will be on the list after the spark stuff.
I will also change my rubber boot between the AFM and the throttle body as it has some cracks showing.
Other suggestions? Plugs are fairly new. Threw an AFM code on the stomp test.

[shogun]

What about the fuel pump? Check that too, plus
Crankshaft poisition sensor, should be 540 +/- 10%, see here, that is from the M70, but same results from M30 engine http://www.bimmerboard.com/forums/posts/1237505/
What about voltage? Did you check the fusible link? http://www.bmwe34.net/E34main/Maintenance/Electrical/Fusible_link.htm
Fuel pump relay? http://www.bimmerboard.com/forums/posts/366521/
Main relay? http://www.bimmerboard.com/forums/posts/457838/

[ahlem]

CPS is less than 1000 miles old. I will test it.
I pulled the cap and rotor last night. Moisture under the cap and the contacts were quite cruddy.
The cap had a 1990 date on it and the rotor had 1996. These were spares from a half off day at the local LKQ a while back and will be replaced $$$.
The car runs a bit better with cleaned cap and rotor but there is a stutter when stepping on the gas.
Last time I tested fuel pressure several years ago, I had to tee into the fuel supply line. Is that the best way to do the test?
I have no idea the condition of the fuel injectors but with that many miles, they could easily be pretty clogged.
I have a set of Ford 5.0 injectors, are these interchangeable? Will it add 50 hp like the kids on the e30 forums claim?

[shogun]

I do not know the fuel quality where you live, but maybe changing the fuel injector filter, pintle caps and o-rings is a good maintenance idea. MrInjector for example has these kits
http://stores.ebay.com/Mr-Injector/BMW-Injector-Service-Kits-/_i.html?_fsub=643607014&_sid=68034504&_trksid=p4634.c0.m322
I do not know the capacity of the Ford injector, so no comment on this from my side.
The fuel pump you can test easy with a PET bottle like this http://bmwe32.masscom.net/sean750/fuel_pressure_regulators/FuelPressureRegulators.htm
Nominal data:

The M30 fuel pump is originally Bosch
operating pressure is 3 bar
conveying capcity at 12 V 1.9 liter/minute
conveying capacity against counterpressure 875 ccm/30 seconds
Power consumption is 5A

Fuel pressure testing is in the shop manual in detail https://www.bmwtechinfo.com/repair/main/

What you also should check are the vacuum hoses on the M30 engine, especially the 2 under the intake, as one of them also controls the fuel pressure
http://www.nmia.com/~dgnrg/hose_map.jpg
They could be brittle and leak.

[ahlem]

The vacuum hose from the FPR to the underside of the manifold is very suspect.
It currently has a splice fitting in it as it was decomposing at the FPR end and had to be cut back.
Nothing audible but still suspect.

[ahlem]

Here is the update...
The new cap and rotor were installed yesterday. All the symptoms of concern were eliminated.
Being a cheap guy, I waited until a little too long to do a routine maintenance procedure.
Thanks for the input.
Now on to the next challenge...

[632 Regal]

Good thing my post didn't stick. I blamed fuel pressure and plugs/boots because so common.

The mustang injectors are better than the stock BMW ones. You should get an increase of at least 100hp... In actuality your engine should get back to it's normal output, possible a couple mpg more if you go with the better injectors.

Amazing how the simple things mess people up.

Edit: Change the fuel filters ASAP. They arent anything really til they clog.