I Have Fire And Fuel To The Rail But Won't Start

[clarkstreet]

My 1989 m30 735i started,ran rough and died.When I tried to restart it would stumble and die.I've changed the fuel and main relay.Put my spare ECU in.Have strong fuel pressure at the rail.Removed a spark plug and have spark.Thought it might be the CPS.Would I have spark?

[Ross]

no spark when the CPS dies.

[clarkstreet]

Where do I go now?

[yaofeng]

Measure the two leads of the CPS connector for specified resistance. Use your Bentley.

[Rus]

Get some starting fluid from your local parts place and spray some into the throttle body. Alternatively, take off the vacuum line going to the fuel pressure regulator and spray fluid in through that (direct shot into the manifold). Crank it over. If it tries to come to life, you are having a fuel issue. If the injectors aren't firing, you'll never get fuel into the cylinders. Also, you might have spark, but it might not be in proper time. A faulty CPS could be fooling the ECU. Keep us posted.

[clarkstreet]

Thanks for the help.I'll try all the above and see what happens