Hard starting - Fuel Injectors??

[honeygrove]

I'm having difficulty starting my 1976 3.0 Si that has an updated fuel injection system from a 1981 528i. It seems to take many tries before the engine catches. I've checked the timing and the cold start which appear to be fine. My mechanic seems to think the problem is leaky injectors that won't hold pressure. Is this a reasonable deduction or should I be exploring other areas?
Thanks in advance

J.B.

[Peter Florance]

I'm having difficulty starting my 1976 3.0 Si that has an updated fuel injection system from a 1981 528i. It seems to take many tries before the engine catches. I've checked the timing and the cold start which appear to be fine. My mechanic seems to think the problem is leaky injectors that won't hold pressure. Is this a reasonable deduction or should I be exploring other areas?
Thanks in advance

J.B.

No probably not

Is is cold start or warm restart that is the issue?
He may be thinking about Kjet which requires residual fuel pressure to open injectors. Cold start valve will work with just a little pressure

I'd check to make sure fuel pump is working and look for cracks in intake boot hose (underneath where you can't see)

[Mike W.]

It could be leaky injectors, but it would manifest itself by acting flooded, since gas would have leaked down into the manifold while the car was off. Next time it happens, with the key off, pull the big plug off the ECU in the glove compartment. That will shut off the FI system. Then try to crank it and start it, if it fires up and runs briefly, then dies, it may in fact be the injectors. You just burned off the fuel that leaked. Again, with the key off, plug the ECU back in. If it starts and runs normally, it might just be your problem. Try running some Chevron Techron thru a tank or two, I've had very good luck with it. Not Fuel system cleaner with Techron, the straight stuff. It's a little pricy, but not compared to injectors. A bad fuel pressure regulator is also a possibility, which is much easier and cheaper than a set of injectors. Rock auto sometimes has them stupid cheap, right now they have half a dozen left on closeout for 20 bucks each. But it's probably not the injectors, I've had few problems with E12 era injectors leaking, unlike E28 ones.