The intermittent cold start problem with my 1995 850 turbo progressed over a period of about a year. Started with an occassional initial stumble and rough running when started and then moved very recently to hitting on two or three cylinders and then dying. In the latest stages it would run for 1-2 seconds and then die.
Symptoms: Had to be left cold over night for the problem to occur. Would not run and die on repeated attempts unless the key was switched all the way off and then on. If left in position II and then turned over: nothing, no fire in the hole. It would eventually start, after 3, 5, 8, 20 attempts and then run fine. And restart fine and endlessly when warm.
My guess: a fuel pressure problem, felt like a loss of “prime” in the fuel injection system. Did not feel electrical. I was wrong apparently.
Actions: Cleaned all the grounds, replaced the ECT sensor ($50) [thought the ECU didn’t know it was “cold”], checked every connection I could find, took the fuel pressure relay out and cleaned it. Gave up and took it to the dealer at my wifes’ insistence (no sense of adventure). Dealer had it for two weeks, every time they fiddled with something it would start and then the same problem would occur the next morning. YOU HAD to let it sit overnight. They replaced a fuel sensor (not the relay), resoldered the fuel relay, replaced the fuel pump and FINALLY replaced the fuel pressure relay with a new one. PROBLEM SOLVED, so far... I was getting pretty pissed because I could have played replace-the-part with every thing in the fuel delivery system. Very tricky to diagnose, mechanic said he rarely saw a bad relay in an 850, although now that they are getting older its more common. Thanks to Erwin and russb for their help. Hope this helps someone else. Replace the relay, it’s going to die anyway.
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The 240 series cars were notorious for bad fuel relays.
Did you have to pay for the parts you didn't need?
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RussB in Ct '96 855T - '91 944T

Same exact problem.
Though to get it going I had to pull the fuse on the injectors to get it primed... or so I thought... I have to tell the guy who bought it from me.....

Jim

Yes and no. They replaced a fuel suppression relay and charged me for that but after keeping the car for a week they were apparently so relieved to fix the problem that they have yet to call me back or send me a bill for the Fuel Pressure Relay. They probably came out close enough on the one I didn't need that they didn't want a customer playing 20 questions after the fact about how come they didn't just replace it in the first place. Glad to wash their hands of me I guess. Frankly I sent the car in to be diagnosed, with the intention of replacing any parts myself. Kind of went "Oh, S***" when they replaced the fuel pump, since their price was three times what I could have done it myself for. But since they had the car... As it was the car is starting normally now, some ten days after they sent me home. I guess that was the problem. Glad it's over. Can't wait to see what comes next. It's been a pretty reliable vehicle, this is the first ugly problem I could not fix.
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Where is the relay located ?

I believe this relay is located under the electrical control box cover next to the fuses. You have to remove 4 screws and remove the cover. Not sure which one is the fuel pressure relay, they may be marked or that number may be in archives here. I didn't get the original back yet from the dealer because they haven't billed me for it yet. Sounds strange, but I think that they fumbled the ball so badly that they just want to forget it, especially after replacing a fuel suppression relay, located under the fan shroud, that did not fix the problem. Maybe the cost is a wash. Good luck. At 105K I'm going to start replacing stuff as $ permits just because I know it's not going to last forever. The wife gets real testy when she doesn't have a car.
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