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Re: Still have hard start problems - any ideas?

You wrote: 
>I am still having hard start problems with my 87 5KTQ after replacing 
>I think all injectors are O.K. although they are hard to test when the
>engine is hot.
>It seems to be a fuel dilevery problem because the engine dosen't
>stumble or act flooded when it does fire up. It seems that if the
>cyclinders were getting fuel during long cranking times it would act
>flooded when it finally did start.
>I have checked for vacuum leaks and the Intercooler to intake hose.
>I have been reading some diagonistics from a Mitchell manual and it 
>the coolant temp sensor should read between 60-1000 ohms. I checked 
>this morning when the car had sat overnight (ambient temp approx. 30 
>F) and it read 1950 ohms. Both of the single wire (blue wire ) temp
>sensors on the left side of the engine read 1950 ohms. I swapped the
>wires to them and this didn't help. I think the one on top of the
>coolant hose housing is the one for the ECU - not sure what the other
>one is for (towards the front of the engine block under the HP pump
>Mitchell manual mentioned the idle stabilizer could cause hard 
>They say to hook a dwell meter to OXS test connector and look for 80%
>dwell while cranking. Not sure what this dwell is or how to test it 
>a regular DVM or where the OXS test conn. is located.
>Could still be pressure problem - how can I troubleshoot the fuel pump
>check valve?
>TIA for any ideas on what to do next.

Connect a Bosch fuel preesure guage to the out side of fuel filter.  
Run pump w/jumper, and wait to see if system holds residual pressure.
Also, take the screw out of the far end of the fuel pressure 
accumulator(next to tank) and see if fuel drips out.  If it does, 
diaphram is faulty.

Good luck!

Jeremy Walters