Hey guys,
Got an issue with my 99.5 ford f250 super duty 7.3 PSD around 350k miles.
It seems like it takes a long time to crank before firing (4-5 Seconds cold/unplugged)

(It takes about 3'ish seconds when warm or driving it recently).
It starts quicker/easier when it's warm out or,
if I've been driving it and,
also when the block heater is plugged in.

Recently,
It's started to crank and not start (cold, or no block heater plugged-in) on the first crank, but when I turn the key off and back on and wait for the WTS light to go out again it fires right up even cold/no block heater.

It's also "surging" (lack of a better term) a little, cold from 700'ish rpm (normal) to about 900'ish rpm, and stays there, but if I tap the pedal it resumes normal idle and doesn't do it when warm. (I initially thought it was normal because it only does it when it's cold and increases from 700ish up to 900ish and stays there until it's warm or I tap the pedal.)

When it's running, it runs great, pulls hard and doesn't miss a beat, runs all day/night long, loaded/unloaded!

(IT WAS DOING THIS PRIOR TO THE SERVICE.)
But I recently did an oil change (Rotella 15w-40 and k&n oil filter and cleaned/oiled k&n air filter, used the same Rotella the last oil change also.)
I'm also getting ready to change the cam position sensor (truck seems to have a VERY slight rough idle, but it's never stalled/stopped.)
Not sure if it's associated or not...

maybe a leaking HPOP??? (But wouldn't it do it warm also?)
What do you guys think?
Any direction will be much appreciated,
Thanks.

 

At first I was going to give you advice, but it might be much better to get advice from the members who are a lot smarter than I. Please post this in the 7.3 forum for your year of truck, and I assure you that the wealth of knowledge will be overflowing. They have a better way of explaining, and pictures that I cannot provide. They WILL get you fixed up.

 

Hopefully a mod can move this thread.

Cold starts. The glow plugs will burn for up to 2 minutes. What is likely happening when you try to start it the first time, the plugs haven't warmed it up enough even though the WTS light goes out. Next time, turn the key on, watch the WTS, when it goes out, give it another 5 to 10 seconds, then start it. I bet it starts.

The other condition you refer to is what many call the romps. Some guys run synthetic, and never have an issue. I have experienced it a couple times on my 7.3's but it's been a long time since I've heard it. I'm not sure what causes it. Synthetic oil has eliminated it for some people, but like I said, I don't believe that's the cause.

 

Thread moved.

 

Thanks Scott, sorry I posted in the wrong spot.

SGarder and John I appreciate your input!
I'm not running syn oil, yet, my next change I was going to syn oil, (I was doing 2 quick oil/filter changes to "flush" the oiling system prior to going to syn.

I'll give that starting technic a try tomm, I'm also changing the Cam sensor tomm, are you think my glow plugs or controller/relay are at fault?
Thanks again guys.

 

Not necessarily. They operate on a timer/temperature control thing somehow. If the glow plugs are bad, use Motorcraft only. I don't know how they know to burn longer when cold rather than when warm. You'll notice the WTS light won't be on but for a few seconds when the motor's warmed up. But can go for 30 to 45 seconds when real cold. Like I said, give it another 10 to 20 seconds after the light goes out before you crank on the motor. BTW, how are the batteries?

Also, the cam sensors can be picky. We've found on here that the best ones are Ford or International.

 

I'll give it a try and see what happens.

Batteries are newer and good.
I bought a BWD cam sensor already are they bad units?
I'm not familiar with an auto parts store that carries ford or int. units, who has them?
Thanks

 

There are several places. Rift Raft to name one and a dealer for the other.

Motorcraft Cam Position Sensor CPS 94.5-03 - Riffraff Diesel Performance

Most people in clod climates would love to have what you consider an issue. 3-5 seconds.....

But, needless to say YOU know your truck better than anyone.

Do you have access to a bi-Directional Scanner to monitor PID's. That's where the meat is.

 

Thanks for the link/info Tom
does anyplace like napa, O'Reilly etc carry them?

I'd agree 100%, complaining about 3-5secs makes me sound like a whiner lol
But my main concern is the fact that it takes 2 cranks to fire her cold and unplugged in 30 degree weather (+/-).
So if there's an issue I'd like to fix it before failure or a no-start sit.

I don't really have access to a scanner unfortunately

 

Without a Scanner, I would focus primarily on the Glow Plugs and Circuit which is easily tested with a DVOM.

 

I see a mod moved you under the information waterfall.

1: 350K miles is a lot of miles for not only one set of injectors, but two sets. They are likely getting "cranky" and need their pacifier. Synthetic oil typically helps injectors in cold climates, more so when they have high miles.

2: Glow Plugs need time to heat up, they are like an electric stove burner - but much faster. Like mentioned before... turn the key, then plug in your phone, buckle up, set the heater, adjust your mirror, dial the radio, consult your horoscope - anything to stall before turning the key. Give those hotheads a chance to do their job - anything from 10 seconds after WTS light-out to 30 seconds. If you were in Alaska, I'd say run the GPs for 90 seconds, cycle the key and do another 90 seconds before cranking.

Your engine with 350K miles likely has diminished compression from new - but I'm not saying it's bad compression. With less-than-new compression, the engine relies more heavily on proper GP heat and fuel atomization. Unfortunately... after all those miles, this is when the Glow Plugs may be turning from redhead to grey - and the injectors from fireballs to old flames.

With your age of truck, the need for a scan gauge/tool grows. You asked about the possibility of an HPOP issue. If we were really chasing that, the first question we'd ask is "What is the ICP/IPR at idle?". A reply of "I don't know, I don't really have access to a scanner unfortunately" will then put you in a situation where you have to tear into the truck to find out if you have oil leaks. After getting all greasy, scraping a knuckle, and losing a Saturday afternoon - you find it's nothing more than the wrong oil in the pan. The scan gauge/tool may very well help you avoid that scenario.

A scan gauge might be something as simple as an OBDII adapter you can use on any vehicle, and a $10 app on your portable device.

 

Makes perfect sense Tugly,
Thanks for all the information,
On the top of my list for mods (among others) is a DP tuner so I can scan and keep track of the various PIDS.
I usually throw in a quart of trans fluid in my tank every other fuel up (among CETAN and anti-gel etc) and I'm planning on switching to full syn oil very soon.
Does that "Hot-Shot" stuff work for stiction?

 

Hey Tom thanks for the response,
Dumb question though,
What's a DVOM?

 

You've got some good advice here so far, and I may repeat what has already been said. Now that the disclaimer is out there...


Are you waiting until the glow plug light is out before cranking? The glow plugs will heat for 2 minutes (long after the light goes out) when the engine oil temp is cold. One quick thing to check is how much of a voltage drop you are losing across the glow plug relay. Sometimes these relays die gradually.


The 'surge' up to 900 rpm sounds like the high idle kicking in. Does it happen about a minute and a half after startup? Shortly after, the exhaust backpressure valve will close, making a hissing sound. Both cancel when you touch the brake or accelerator. All normal. Nothing to see here.


A very slight lope at idle is nothing to be overly concerned about. When I am due for an oil change, my lope at idle will lightly rock the cab at a stop light, but I am still on my factory injectors. I tell concerned passengers that the lope is just raw torque waiting to be unleashed.

 

Thomabb thanks that cleared up a couple of my concerns.
"Raw torque waiting to be unleashed" lol
My truck has a very slight...shaking? You don't really notice it unless you look at something in the truck and you'll see it shaking at idle.
I'm not overly concerned about it, but didn't know if it was associated.

Yes sir, I think you nailed the high idle kick in, it idles up exactly as you describe, and if I tap the pedals it drops back down to normal idle. So that's another concern I can mark off my list.

I turn the key on and wait for the WTS light to go out and immediately crank it, I had a ford 6.9idi that the split second the WTS went out I would crank it, that was the best way to start it. So I do the same starting procedure for my 7.3psd, but I'm going to start waiting longer now.
Is there a link for the proper procedure for checking GPR voltage drop?
Thanks again everyone, I really appreciate the help.