1997 power stroke hard start

[deadlift605]

i just bought a 1997 f250 its hard to start you have to hold it wide open and crank it a lot to start and it has a miss and smokes white
just dont understand why you have to hold it wide open for it to start

[dieselgold]

holding the throttle wide open shounldn't do a thing since the throttle is controlled electronically and doesn't register once the truck has started then the throttle will register but not until the truck is running will do nothing holding the pedal to the floor on start up, sounds like your problem is else where, glow plugs maybe glow plug relay???

[Nit]

your problem is teh Glow Plug Relay, you need to replace that first then chase problems from there, you should NEVER, EVER use teh throttle to start the truck , it messes with teh PCM.
To check to see if I am right, tomorrow morning, either have teh trcuk plugged in all night or better yet, take a jumper cable clamp and cross teh large posts of teh GPR under the engine cover, actually remove the cover right away, you will see a relay on the pass side of teh fuel filter, jusmp that for 45 secs then start the truck.

[LabRat]

I'm having a similar problem with cold weather starting. I just tested the GPR large leads...One large lug has a constant 12V while the other large lug is very low resistance ~2ohms. At no time during the glow plug cycle does the 2nd large lug ever register a voltage; more like it's shorted to ground. This thread
suggests both large lugs should have similar voltage. Would you agress that my relay is shot?
Thx

[STurbo90]

[ QUOTE ]
I'm having a similar problem with cold weather starting. I just tested the GPR large leads...One large lug has a constant 12V while the other large lug is very low resistance ~2ohms. At no time during the glow plug cycle does the 2nd large lug ever register a voltage; more like it's shorted to ground. This thread
suggests both large lugs should have similar voltage. Would you agress that my relay is shot?
Thx

[/ QUOTE ]

Yes, when the glow plug cycle is on both lugs should show 12V+. So either the relay is bad, or there is something wrong with the two smaller terminals wires not telling it to activate.

The two smaller terminals should show 12V+ when the glow plug is not cycling. When it is cycling one will show 12V+ and one should show ground(from pcm).

[LabRat]

Close...When off, only one large lug has 12V, the other large lug is ~2ohms and the two small lugs have approx ~100ohms. When cycling one small lug goes to 12V & the other goes to open (no continuity to ground) while the large lugs never change. AFter cycling, both small lugs read 12V. Does this still sound like the GPR or is it now the PCM signal to ground? Thx

[action4478]

[ QUOTE ]
Close...When off, only one large lug has 12V, the other large lug is ~2ohms and the two small lugs have approx ~100ohms. When cycling one small lug goes to 12V & the other goes to open (no continuity to ground) while the large lugs never change. AFter cycling, both small lugs read 12V. Does this still sound like the GPR or is it now the PCM signal to ground? Thx

[/ QUOTE ]It sounds like the PCM is giving it a ground, The other large lug with no reading means the GPR is not closing. Do you hear it click when you turn on the key. Have you checked the large fuses under the hood?...Just a thought....

[LabRat]

It clicks when the key is turned on & voltages appear to be as advertised with the exception of the GPR output. If the fuse was bad I wouldn't expect voltage at the terminals. I shorted the two large lugs together for 45 seconds in attempt to bypass the GPR but the truck still didn't start right up as I've heard from other threads on this subject. Hmmmm...... Sounds like bad GPR but they may still be more going on. Here's the diagnostic I've been using. So far I've only tested the GPR since it seems most likely.

[action4478]

[ QUOTE ]
It clicks when the key is turned on & voltages appear to be as advertised with the exception of the GPR output. If the fuse was bad I wouldn't expect voltage at the terminals. I shorted the two large lugs together for 45 seconds in attempt to bypass the GPR but the truck still didn't start right up as I've heard from other threads on this subject. Hmmmm...... Sounds like bad GPR but they may still be more going on. Here's the diagnostic I've been using. So far I've only tested the GPR since it seems most likely.

[/ QUOTE ]I agree on the fuse... you have voltage to the two small terminals, but only one of the large ones powers up. The one that has power , gets it from the starter relay on the rt fr fender. If you jumped the GPR across the terminals it should have activated the GP's for 45 sec's. You may have to check the GP's & see if they are any good.... [img]/ubbthreads/images/graemlins/shrug.gif[/img]

[Nit]

exactly right, if your GP's work then shorting the relay will work