Ok guys, I know you are brilliant, I've looked thru about 15 pages so far about cold start, gps and gprs. I just bought a 99 SD 7.3 powerstroke, 3rd one I've had. On 35-40 degree mornings, cold start, I wait for glow plug light then start. It goes Romp, romp, romp idle, spewing white to black exhaust pulses, and has no power backing up then driving til it warms in a few miles. By no power I mean you can give it gas pedal but it barely moves, and only up to1500+- RPM.I was hoping it was gpr but when I hooked a test light to the right side big post, it lights up with key on, although I thought it strange that it stayed lit to after 30 seconds. Sound like bad glow plugs? I remember I had the gps replaced in my 99 F350 when it would not start , but that was at 235,000 miles, this truck has under 150K. I'm hopin its not the gps and or injectors but it prob is the gps. 2 other things, the aluminum intake tubes at the Y have dirty smudge on them, I think that means the rubber connectors are loose or bad? Lastly the hood struts are shot, where to get them and how much$ ? Thanks guys

 

Your glow plugs will stay on up to 120 seconds during cold starts. The WTS light on the dash is independent of the GPR on time. You have a working GPR and you probably have bad glow plugs. The only way to tell is to ohm them out and see what you have.

Cold start romps can also be caused by the ICP sensor. The sensor tells the PCM what the pressure is. If it is bouncing around it will create issues like you describe. You can try to unplug the ICP and see if you get the romps. If not, you may want to look at the sensor.

 

I find from reading that for most people switching to 5W40 synthetic oil makes a big difference on the romp romps on a cold morning.

As far as power, my 99 is the same way and I think its the back pressure valve restricting the exhaust off to much to warm the engine up. The engine sounds fine, it will rev to 2K plus with no problem but when I go to accelerate it wont go to save its life. Once the engine temp gauge starts to move showing the engine is warming up then it runs just fine with no problems. My truck is about to roll over 220,000 miles. My engine also smokes a little during this time but once warm its good.

Jeff

 

I agree with the others. Sounds like your GPR is working, and the 5-40 synthetic does make a difference for me. Good suggestion about unplugging the ICP to see if it helps with romps or smoke color. Below are some links to help troubleshoot GP problems. Good luck.

https://www.ford-trucks.com/forums/7...pr-system.html

https://www.ford-trucks.com/forums/8...ck-shakes.html

 

I'll do some testing, thanks guys!

 

How long do you think it takes to replace the glow plugs, sounds inexpensive, but may be time consuming and difficult?

 

I have the same truck ('99 - 120,000 miles) and had exactly the same problem a couple winters ago. I came on this forum and had all kinds of friendly suggestions. I ended testing my GPR, no problem, tested the glow plugs (never really got a meaningful reading from my multimeter - probably the operator), changed the port side glow plugs (took about 4 hours - its easy if you have the right tools. Not sure about starboard side), and none if it make a lick of difference. Someone had suggested i switch to synthetic oil early in the thread and i thought it was a bit of a crazy suggestion. How could that make a difference??? I wish i had just done that from the beginning, because it completely cured the romps. Night and day. Trucks starts just fine now and i don't worry about it when it gets cold out.

 

interesting, the former owner just had the oil changed at a Ford dealer, do they use a non syn oil?

 

Romps are not necessarily bad. In cold weather, you should let the truck warm up before driving anyway.