3.3L hard starting cold

[stonerce]

1992 Grand Am is very hard to start when cold. runs fine after first start of the day...
changed the computer, changed plugs, changed plug wires, changed fuel pump, changed IAC Valve...car runs better after parts changed but still very difficult to start on cool morning 60-70 degrees? not the battery, the starter spins the engine no problem, has spark when pulling plug you can see the spark jump the gap. you can hear the pump run till the oil press go almost to zero (does this suggest the fuel pump relay is out? will that affect the computer and starting?) when the day gets hot say above 74 - 80 degrees then i can get it started...

Thanks for your help

[GTP Dad]

Is the CEL on? If not then try the fuel pressure regulator. It may not be holding pressure and causing the engine to be hard to start.

[stonerce]

Originally Posted by GTP Dad

Is the CEL on? If not then try the fuel pressure regulator. It may not be holding pressure and causing the engine to be hard to start.

check engine light is not on, however i do get a check gages light from time to time but no gages are out of range. I will check fuel pressure reg....since it is only cold start problem could the temp sensor be telling the ECM engine is warm and not giving a rich start signal to the injectors?

[maxwedge]

Also yes on the temp sensor.

[stonerce]

Originally Posted by maxwedge

Also yes on the temp sensor.

I changed both temp sensor and coolant temp sensor, gage now reads 240 at normal operation temp, checked with infared thermometer, reads 195-200 maybe that has created another problem. also changed the fuel pressure regulator, tried to start this am and it took about 5 min. of cranking and cranking before finally getting started. I notice that the fuel pump runs till the oil pressure is near zero...would the fuel pump relay cause a hard start when cold? could the ignition switch be causing the car to turn over but not allow a start? that doesnt seem likely since the time i pulled a plug i was getting spark across the gap just fine...once started the car runs fine.....till it is off overnight, pretty frustrating....

[maxwedge]

Take a look at the oil presuure sending switch and wiring I believe this is in you fuel pump activation circiut, autozone.com/repairinfo has a wiring diagram showing the oil switch in that fuel pump circuit.

[stonerce]

Originally Posted by maxwedge

Take a look at the oil presuure sending switch and wiring I believe this is in you fuel pump activation circiut, autozone.com/repairinfo has a wiring diagram showing the oil switch in that fuel pump circuit.

i read in a repair manual that the fuel pump would shut off after 2-5 seconds when key is turned on ... if relay is out then the pump will run till the oil pressure drops to about 4 psi....the real problem is that the car is very hard to start when cold... I have put a new fuel pump, temp sensors, pressure regulator, plugs and wires, IAC valve, run several bottles of fuel injector cleaner, changed a couple of vacuum lines, the Computer, a new battery that spins the engine really fast, and i am running out of good ideas and money....over $700 in parts and days turning wrenches and getting parts.....what would cause the hard start? once warm the car starts up in less than a second...

[Kristal]

Your promlem sounds alot like mine....If you find a solution, please let me know.....92 Grand Am won't start and then some.......Thanks!

[richtazz]

I agree with the earlier post that your fuel pressure regulator is going bad. Any of the other sensors will trip a check engine light.