In the words of my friend Critter "Duuude, you got essues!" OK, so here is my issue. Got in my truck yesterday, 1997 F350, started fine no funny noises or anything. Drove about 25 miles. Got in about 3 hours later and it fired right up but had a funny surg in RPM's and quick drop, almost like a gasser with a huge cam. Give it a little fuel and then every thing evened out. Now it does it every time I start it up. Ran codes and none found. New filter,replaced after surging began. Filter was pretty clean. Fuel in the bowl looked clean. Any guesses?

 

If it's new to you change the oil first before trying to troubleshoot anything unless you know for sure PO did and use proper oil for our diesels.

 

Not new to me, but due for an oil change soon.

 

x2. Those injectors need clean oil to fire properly.

 

i had the exact same problem, got my truck about a weekand a half ago and it would surge slightly then smoothen out, ended up being an EOT(engine oil temp) sensor on the hpop, ford doesnt stock them so i called around eventually till i found one, 10$ for it.

 

Where did you buy it? Might be some handy info. I will look up the location of the sensor, but in case I can't find it, where on the HPOP is it?

 

if your looking down at the hpop its in the back on the righ thand side, cant miss it, theres only 2 sensors i belive on the hpop, when you unplug it if you do, a ton of oil comes out so be prepaired, i got the sensor from greensalescompany.com, there awsome jsut give them a call, i can get you the part number if you need it, makes the process 3x as fast.

 

Thanks for the link. Sure post the part number.

 

If you have an auto trans is could also be the transmission range sensor. While its surging put the truck into neutral. Or start the truck up in neutral if it surges every time you start it. If it still surges you need a new sensor.

 

Got in the truck this morning and it fired up no problem. Started it in neutral too, and no problem. I haven't changed the oil, or anything yet, so I'm stumped.

 

Yes, AT and it is still surging. I started it in neutral and starts fine. Kill it and try in in "park" and it surges. The surge evens out to a smooth idle with a couple run up's of the RPM's. So if it only surges in "P" is it the range sensor?

 

Yes it sounds like the TRS (trans range sensor)

 

my truck surges at idle to sometimes on start up and then it smoothes out but it's a manual

 

That must be the sensor they tried to sell me at auto zone. Idiots. haha. I asked for a speed sensor, they pulled a range sensor out. hahahahah!!!!!

 

Holy crap guys. I love the internet. I have been thinking I need a new set of injectors or a new high pressure oil pump or some really expensive engine fuel system repair.

Who would have ever thought to shift into nuetral and start the truck. I have been dealing with the engine surge on start up for over a year now. I lived with it by running at fast idle for a few seconds after starting and it smoothed out after that. But when starting in nuetral it's purfect and idles fine from the start.

I guess I'm off to find a transmission range sensor now.

Thanks guys!!!