87 528E Extended crank and no start.

[DrtyE30]

My e28 last week started to randomly have extended cranks, now if I let it sit for more than 5 mins it won't turn over right away. I can hold the key and it just cranks and cranks, doesn't how many times I do it. But once I get it running its fine, a few times it stalled right away but runs smooth. This is my first b27 and I don't know a bunch about it. Any ideas?

[DrtyE30]

Changed the DME relay,fuse is good, pulled the fuel line and wasn't getting fuel. But if I push start it it will stay running even if I rev it high or drive it. Would the crank sensors do that?

[Cletonius]

If your crank sensors are bad your car shouldn't run at all. It's worth testing them but I don't think that's the issue. You might want to replace all the fuses. My car became a bunch more reliable once I swapped out the 20+ year old fuses.

Edit: what about the fuel pump relay? Might be sticking?

[DrtyE30]

If your crank sensors are bad your car shouldn't run at all. It's worth testing them but I don't think that's the issue. You might want to replace all the fuses. My car became a bunch more reliable once I swapped out the 20+ year old fuses.

Edit: what about the fuel pump relay? Might be sticking?

That's what I thought as well, but I just got some fuses and will put them in when I get out of work tonight. I tried swapping it with a questionable relay I had but once I get to my shop i'll try it again.

[harold30]

Changed the DME relay,fuse is good, pulled the fuel line and wasn't getting fuel. But if I push start it it will stay running even if I rev it high or drive it. Would the crank sensors do that?

If you pulled the fuel line and not getting fuel then it must be either faulty fuel pump or clogged fuel filter...

If this happened to you when your engine is hot then the fuel pressure could be a problem, it will flood your intake manifold with fuel and thus hard starting occurred. Just based on my experience but I'm sure some experts here can answer you promptly. hth

[DrtyE30]

If you pulled the fuel line and not getting fuel then it must be either faulty fuel pump or clogged fuel filter...

If this happened to you when your engine is hot then the fuel pressure could be a problem, it will flood your intake manifold with fuel and thus hard starting occurred. Just based on my experience but I'm sure some experts here can answer you promptly. hth

Well I kept messing with it and changed all the relays and fuses and got it to turn over. But now it won't rev past 4k rpm. It starts up every time but the whole not going past 4k thing I need to figure out, not having a power band sucks!

[dnguyen1963]

Your TPS might be feeding the wrong info to the DME.

[DrtyE30]

Your TPS might be feeding the wrong info to the DME.

That makes sense, I have a spare TPS that i'll throw in this weekend.

[DrtyE30]

Try changing the tps, dme, fuel pressure regulator, vacuum hoses, and I still can't get it to rev past 4k. If its dead cold it will go to 5k but struggles to get there, when it's hot it sounds like fuel cut off when I reach 4k. Also since I did all this work when its cold I have extended cranks, but not at any other point.