I purchased a single owner 89 325ix back in Jan 2011. 22 years and one owner. The car looked great and ran ok. Even the power antenna worked! I paid $2,500. The car had 197k miles on it. About a month into owning the car I could tell that a vacuum leak had developed. The car wanted to stall at idle (red light or stop sign). I needed to put it in park to keep it running. I sprayed some starter fluid around the engine and found some trouble spots. I replaced the idle control valve, breather hose and two gaskets on the throttle body. I also replaced the spark plugs and installed a new valve cover gasket. Took it for a ride and it felt like a new car. But it only lasted about 3 minutes then it went back to a rough idle. I sprayed some more starter fluid around and it looked like I needed a new head gasket (sucking in air under where the breather hose connects to the valve cover). So I did the head gasket, intake manifold gasket, timing belt, fuel pump, water pump, thermostat, new drive belts, exhaust manifold gaskets (did I forget anything?). BTW when I did this the coolant and oil were mixed together in the cylinders. Car still runs like crap. Now someone is telling me that the fuel injectors need to be replaced. If the car is cold and I try to accelerate the car hesitates like it's going to stall and it goes nowhere. I think a new fuel pump with the old injectors was not a good idea. Looks like the old injectors can't handle the added pressure of the new fuel pump? I'm in for about $4,700 now. If I have someone do the injectors it will run about $900. If I do it myself maybe I can do it for less than $400. The tires match and have plenty of tread and the all wheel drive works. Should I put more money into this? Is there something I'm missing? This is my 4th e30 and this is the 1st one that has me scratching my head. I'm frustrated that it doesn't run like a Bimmer.
If you used oem-spec parts, I wouldn't expect fuel pressure to be any different. Doing all that work, presumably you have a Bentley manual; you might want to run through the fuel system diagnostics before just throwing more parts at it. Obviously you like E30's, so if you want to enjoy it for coming years, I would say why not get it worked out. With a head gasket, you've already done some of the bigger engine-related projects you'd likely face. I'd suggest emailing Mike Miller, he has excellent insight and responds quickly, and keep us up to date on what you find out. There's lots of places that will service/rebuild your fuel injectors, and there are sellers on Ebay selling rebuilt ones for not all that much $$$. I think E30 stock injectors are 14 lb/hr. If you get into that, test your fuel pressure regulator, although I don't know offhand if the fuel pressure regulator could be part of your idle issue. Original fuel lines are probably hard as a rock, wouldn't be any surprise to need new fuel hose at this point, although being around E30's for a long time, you presumably are aware of that.
I didn't see a fuel pressure regulator on your list of replacements. Usually when they go bad they end up delivering too much fuel, resulting in poor idling but running better under throttle. You could test your fuel pressure, or swap your regulator with a known good one to see if that helps.
I did buy the Bentley manual. I will replace the fuel lines and test the fuel pressure regulator. I'm a hack at best. This is the 1st e30 that I worked on. The other three e30s that I've owned I brought to Schneller in Newbury, MA. Trying to save some money now + I always wanted to test myself and learn how it all works under the hood.
BMW fuel lines are printed with at least a year stamp, or maybe a month/year stamp; if they've never been replaced, you should be able to see that, but if they were replaced with oem, you should be able to see that too. Check the lines before replacing, it is possible they may have been replaced recently enough you may not need it yet - but, if you want to do it for peace-of-mind, certainly nothing wrong with that. You'll need small hose clamps, unless you want to opt for the original crimp-type; which is also an indicator if they've been replaced - the original lines will have crimped hose clamps. If you did the head gasket yourself, I'd say that takes you up at least one level from 'hack' status.
If you replace the hose clamps, get the proper Euro ones, made by Norma, Zebra, or Wurth. They have a rolled edge so they don't cut into the hose when tightened. Available at import parts places, shops and the dealer. Hopefully you've discovered the dedicated E30 forums. Many DIY articles and FAQs there: http://www.r3vlimited.com/board/index.php http://www.e30tech.com/forum/index.php http://forums.bimmerforums.com/forum/forumdisplay.php?f=20
