Been working on a '97 F-350. When I first got the truck, the ICP looked pretty good, actually... 600psi @ 10% and 2500psi @ 32%. Seemed a little slick to me, but hey, might be them SS's. Boost never got any better than 10, maybe 11psi... no smoke I could see, but the truck was a dog. I couldn't maintain the speed limit hauling nothing but itself up a hill. So I figured either a boost leak, lack of fuel, or both. It was leaking fuel and I smelled exhaust. We also had bad oil in fuel... one nasty fuel filter!

We decided we were gonna freshen up the truck with new O-rings for the injectors, HPOP, IPR, and turbo. Rather than mess with the bowl, we deleted it and went with an SD pump and readily-available canister filters. We also did a 6637 and 3" dp and 4" tp. The truck wound up having a pretty bad exhaust leak... the collector was loose as I removed the turbo and the right up-pipe fell outta the collector as I pulled it. Bought the taller gaskets and I tightened it to where I stripped out the short bolt I had bought... got a long one, problem solved. We also put new intake boots on as well.

Here's what I have now: I know I've got fuel... everything fuel-related was pulled and check and I've got a healthy 65psi. Boost is now up to 15psi, maybe 16psi in 1st and MAYBE 2nd gear @ 3000RPM's. Not great, but definitely better. I can SLOWLY accelerate up a hill now, but it's in 3rd gear that I can't get any better than 10 or 11psi of boost. I'm pretty close to 3000RPMs in 3rd gear (after a down shift) and can't do better than 10-11 psi. I'm gonna do a thorough check of the ups, collector, and flange, but I'm pretty sure I'm good there. Gonna do a boost leak test on the compressor side when I make my tester.

Something else I had was at startup (cold), ICP was 700-800psi @ 20% @ idle. A few minutes and the ICP was back to 600 and still 20%. As soon as I started driving, the DC came down and I had the normal 600psi at 14%. I'm assuming that was due to being cold... supposed to wait until up to temp to read that stuff. Also, ICP was now 2500psi @ 38-40%... I wonder what's up with this? One other thing I don't get is how it idles smooth when cold, but as soon as it warms up, the truck rocks with the idle. Not really rough, just not smooth. ICP is normal, too...

So here's what I'm thinking:

For the ICP, I'm thinking weird numbers were because it was cold. As for why the numbers are now higher, but closer to "normal", I'm not sure... I did leave the check valves out (Terminator does this with ALL their pumps).

For the boost, I'm gonna recheck the exhaust side and then build a boost tester and check the compressor side. Only reason I'm not really happy with the boost I've got now is because I did a truck that was nearly identical to this one and we made 20psi EASY... maybe 21 or 22psi if we hit it right.

I also have a few other ideas:

MAP sensor? Need to unplug it tomorrow and see how it runs. Only reason I suspect this is no smoke with the lack of power and it does seem to feel "erratic". Truck has great power in the low end until it starts getting to where it needs more boost.

ICP sensor? Was not replaced, but no major oil in it. I think the oil I saw was just mess from the stuff that was leaking to begin with. This thing was a mess, too! I'll see if it reads atmosphere tomorrow before I start it again.

Bad injectors? I've heard of bad injectors causing the rough idle when warm... ICP is great and it fires really quick, too. I'll be pretty sure they're at least worn if we keep getting fuel in the oil even after the new O-rings.

OBS tuning? I have got a DP-Tuner burned for this truck sitting in a box... I noticed these trucks idle lower than my SD. When "cold", it is idling a little higher. Curious to see what these tunes will do, if anything. Got a high-pressure crossover on the way, too...

And one final question: tranny? Shifts good and is there most of time except for 3rd gear. I don't know if it's the tranny not putting it to the wheels or the motor not pushing hard enough. I do get a weird "whacking" sound when I'm cranking. At first I thought it was the new exhaust, but when I looked at it, this was NOT the case. Almost sounds like it's coming from the torque converter area? I need to look at it some more, though.

I'd also like to note that I did make sure to drive the air outta the truck before doing any data logging... been a good 100 miles before I watched any of this. I still need to run the KOER, KOEO, contribution, and buzz tests, though. I'll be sure to post up about that. No codes other than "KAM error" (pulled the plug on the PCM to get the code for the DP-Tuner) and "ICP higher/lower than desired" (no oil during first startup after O-rings). I forgot to clear those, but I figure them to irrelevant. I'll see if anything comes back.

So yeah, I'll admit this is alot... if you're still reading, I'm impressed. I'm not clueless, I've been into quite a few of these trucks. I just wanna see if there's anything I've overlooked... what's your input?

I also want to check the HPOP level... make sure it's not draining. I'd also be curious to see if the oil on the end of the dipstick has got bubbles in it after I run the truck... not sure what it'd show if anything, but it'd definitely be something. Gonna do an oil change, too. It's time!

 

I'd do injector o rings. Could also check compression while your there. A buzz test for sure.

 

Give us some more info on the truck itself if you can.

What kind of mods have been done, Mileage, etc. Stock injectors? If so, 15 PSI is pretty good (or about normal) for stock AA sticks and no chip.

The ICP pressures, I assume you're reading that with a scanner or AE? What are you using specifically? Are you reading the boost numbers with a scanner as well or with an analog gauge?

I would give it an oil change as well, since the injectors run on oil and it sounds as if it is due anyway.

Can you feel the TC lockup after the 2-3 upshift? If the TC isn't locking that will definitely make the truck feel sluggish in 3 and OD. You should feel 4 distinct "shifts": 1-2, 2-3, TC lockup, and then 3-4(OD).

I second your idea of unplugging the MAP and taking it for a spin as well to be sure it acts the same. A bad MAP sensor can make the trans shift screwy too.

You obviously know your way around the 7.3 and you've got a really good start on this thing, just give us a little more info and I am sure there is someone here that can help you out.

 

I have done injector O-rings already... I forgot to mention that. That's what I get for 2am I guess. As for compression, I'd really prefer to not have to go there just yet. It starts too well when cold, in my opinion, but you never know. Buzz test is definitely going down, too.

It's a '97 F-350 4x4 CC LB with 262,000 miles and stock injectors. As for mods, we've done a 6637, 3-4" exhaust (no cat), gutted/deleted EBPV, fuel bowl delete w/SD pump and canister filters, and eventually an HPx when I get that, too.

I've been using AE to scan. Boost is based on AE right now, but I do have the gauges to go in there, just waiting on the pod. I just know that I've seen 20+ with AE on another truck. But that's what stumps me is that I know 15psi isn't bad, that's why I have to wonder if it's the map sensor? I couldn't figure out why it didn't smoke with the bad exhaust leak it had.

I can feel the shifts, but I don't like when it shifts when I'm standing on it. I'm not sure if it's in 3rd locked or 3rd unlocked when I downshift... I'll be sure to double check. But I have felt every shift, usually when I'm not asking much is when it shifts nice. I will say that when the truck isn't up to temp, it's pretty quick, but it doesn't go up into 4th when it should, almost like the truck thinks I'm standing on the pedal. A few miles later and it's fine... mine was a bit odd like that until I got my valve body and tunes. Might be related?

Thanks for the input, guys... I'm gonna be poking around it today.

 

That's better! Thanks for the info.

Alright, one at a time, here goes.

I don't think you're dealing with a compression issue, or you would have a lot of blowby. Take the oil cap off, turn it upside down and set it over the opening in the valve cover if it blows off, you have a blowby issue, if not and it just kinda rattles off there you're good.

AE will give you as reliable readings as the PCM is seeing, but the MAP sensors are known to vary in readings from the actual boost levels the engine is seeing. It is an approximation, so it's possible to see the 5 PSI variance that you're seeing between this truck and the other truck you have worked on. Try running the truck down the road with the electrical connector on the MAP sensor unplugged and see if it makes a difference. If it doesn't I think you're doing pretty well for an OBS PSD with stock sticks.

In short, the stock shift points in the PCM for the E4OD , yeah they --- SUCK! Put that DP tuner Chip in there and I bet that issue will be a lot better. Any tuner worth their oats (and DP definitely is) adjusts the shift points and line pressure to make it shift a lot better. When the engine is cold, it will shift into 4th but it won't lock up the TC, which makes it feel like it hasn't shifted into 4th. That is normal on the E4OD, the PCM keeps the TC unlocked to create friction and warm up the transmission fluid a bit more quickly. Again, tunes should help the screwy shift strategy a lot.

Another thing to remember is that if you're comparing this truck to your Super Duty, it isn't an apples to apples comparison. Even the e99 7.3 got bigger stock injectors than the 90cc injectors in the OBS. With your truck being an e99 your turbo is similar, but the injectors are still bigger than the stockers in the OBS. A little more fuel makes a big difference. That's why the stage 1 (160cc) sticks are such a good upgrade on the OBS.

Get that chip in there and see how you like it then, I am betting it helps a lot.

 

Unplugged MAP... no change. Replaced the MAP line.. no change. Everything else looked good. Exhaust side looked clean with no soot and the compressor side, other than around the MAP line nipple looked clean too (there's still some oil residue that shows when it leaks). Still going to build a boost tester, though.

Decided to run some tests:

KOER passed
KOEO passed
Buzz passed
CCT failed... #2

#2 isn't one of those that is a common throw (#3 or #8). Icp looks great so I doubt it's injector O-rings. It always loped a little at idle, almost like one injector wasn't quite hitting it... kinda like when you start it up for the first time after O-rings? It also white smoke when it's 70* out... I think it needs some injectors.

I'm still gonna do a boost leak test and change the oil... I need to check the reservoir tomorrow as well. I'll be putting in the tunes as soon as the pod comes in. The truck won't be perfect, but it's WAY better than it was and it'll help some until we can drop some Stage-1's in it.

Anything else I should check? It might just be me, but it seems like the OBS trucks have more injector issues than the SD's... it's not unusual for an SD to have 300-400K on the original sticks. Only thing I can think of is the fuel systems on the OBS trucks... if they're not working 100% right, the injectors don't get fuel. The OBS fuel system is a menace and I can't think of anything worse for an injector than a lack of fuel. Just me thinking, though... oh well. Thanks, guys!

 

Oh, and Nate... it's got all the shifts it should, with 3rd being both unlocked and locked. Not timed like I'd like, but it's good for a grandpa. Guess these trucks stock aren't meant for a 20yr old with a lead foot...