325e runs GREAT on starting fluid... dies 10 seconds later...

[lovely325eta]

Hi everyone! I've got a head-scratcher for you! (and I PROMISE to post the solution once she's fixed! :) :) )

My 1986 325e will start up on starter fluid, idle and rev like a dream, then die after about 10 seconds (once the starter fluid is burned off).

That tells me a few things:
--Good compression
--The engine is getting good spark

My next thought: is it fuel-related?
--both fuel pumps spin when the engine is cranking
--I disconnected the fuel line to the starter injector, and it fills up a glass with gasoline in just 2-3 seconds

My next thought: is it the computer, relay, or a fuse?
--I put in a new main relay
--I put in a new fuel pump relay
--No blown fuses anywhere
--I even swapped the Motronic computer above the glove box (0261200027)
--No obviously disconnected wires, frayed wires, corrosion, etc. Garage-kept car :)

Brand new, fully-charged Interstate battery.

Pretty good head-scratcher, huh!! My next question - could it be the two crankshaft position sensors? (mine are both on the transmission bell housing). Or maybe a camshaft sensor?

One last thing - the maintenance indicator Green/Yellow/Red lights stay on all the time, even when the key is off, but it has been doing that for years, so I don't think that is related.

Any thoughts would be INCREDIBLY helpful!!

Thank you!!

[325e '87]

Check your engine ground strip, and all the others, including confirming the ecm is grounded. Your injectors won’t fire without a solid ground.

When engine is cold, put the cold start injector in a glass and see that it works. You know the gas is there, now check the injector.

On our ‘87eta there is a crank position sensor on the front of the engine, it’s under the diagnostic plug by the balancer.

The 2 wire coolant temp sensor is important, and the o2 sensor both refine the fuel injection.

The throttle position switch tells the dme to idle the engine, confirm that the switch is good at both idle and wot.

Confirm you have no vacuum leaks, mine likes to leak at the brake booster.

I’m possibly the least experienced here but I’ve got our eta and i cars running nicely, and the eta is a slightly different beast and I happen to have one so I’m helping the best I know how.

[jeffnhiscars]

If it only runs on starter fluid it's 100% a fuel problem. Star with your cold start valve and to properly test for fuel output you measure on the return line at the fpr. You don't give much history but we had a similar problem with an eta and it turns out to be gummed up injectors.

[Prizm]

Had the same issue before happed to be the conector on the afm became unseated. Like earlyer poster suggested test icv is working and tps is reading in all positions and connection is good.

Also check intake boot for rip or vacuum leake has caused no start for me in the past.

[lovely325eta]

Solved!!

Everyone, thank you for your insights!

It was the cold start fuel injector!

I could hear it clicking when forcing power to it, but it was so gummed up, that it wasn't a full squirt. I forced 12v to it at least 20 times, and it finally freed-up, and the car started right up!

I will be replacing it.

Thank you for your help!!!!!