Stalls out during hard acceration, hard to start after

[hedmisten]

I've scoured the Internet and I went through all the troubleshooting but I'm stuck.

When I received the car, it wouldn't idle. I've got it running with a new coolant sensor and ICV. The only problem I'm having is that it takes a few cranks to start, dies under hard acceleration, won't crank immediately after stalls.

I'm currently thinking: crank position sensor and/or Reference sensor. Where else should I direct my findings and how can I test for a intermittent CPS?

Car is a 1987 325e. Motronic 1.0

Thank you so much in advance. I've tried researching everything.

Hunter

[gtdragon980]

Dying under hard acceleration sounds like vacuum or fuel related issues. Does the car smell rich when running?

[hedmisten]

Yes. It smells a bit rich. I assumed that it was running too rich thanks to the coolant sensor.

I can't remember where I saw the diagnosis, but someone said to watch the ecometer and rpms to indicate problem area when it cut off.

RPMS drop, but ecometer climbs higher when it cuts off, making me think it has adequate fuel?

[hedmisten]

Thank you btw

[gtdragon980]

I wouldn't count on the ecometer being a reliable way of testing the fuel. I'm not too familiar with motronic 1.0, so I don't know what your engine electronics or fuel setup is like. Either way, I would check for vacuum leaks, test the fuel pressure (should be around 38psi), and check the FPR line to the manifold and see if there's any gas coming out of it.

[jlevie]

If the tachometer takes a drop greater than the loss road speed would require, the DME is loosing power or timing data. If the tachometer doesn't react, but the econometer drives toward zero there is a fuel delivery problem.

[hedmisten]

If the tachometer takes a drop greater than the loss road speed would require, the DME is loosing power or timing data. If the tachometer doesn't react, but the econometer drives toward zero there is a fuel delivery problem.

So if the tach drops to zero but I'm still cruising at 50mph, chances are that it's not fuel since the ecometer does go up, as the tach falls.

[Andy.B]

A bad supply pump in the tank on the two pump setup can cause the engine to struggle or cut out under hard acceleration. Disconnect the line at the pump and crank the engine to see if adequate fuel is being supplied to the pressure pump. Doesn't go just by sound or vibration, as a dead in tank pump still sounds like it is making noise if the pressure pump is sucking fuel through it.

Sent from my Galaxy Nexus

[Andy.B]

A bad in tank pump can also make it hard to start, as the pressure pump has to re prime and build pressure again after starving.

Sent from my Galaxy Nexus

[hedmisten]

Thanks Andy B. I'll be trying this.