7.3L Miss at Mid-RPM

4.0l sahara · Feb 20, 2016

Dump it into the hpop gear bolt cover

superpsd · Feb 20, 2016

There's a few vendors that sell aftermarket hpop gear covers with a tapped port.

Black 02 · Feb 20, 2016

I was doing some extensive google searching and came across an old thread on the nation. I found a picture of some twin plumbing. Mine is plumbed exactly like this picture.

I found somewhere this is wrong and the IPR should be plumbed into the middle port so it dumps into the "standpipe" and not the right port.

Is that correct?

superpsd · Feb 20, 2016

I am not sure but it took me a second to find this picture. Not sure if it helps.

psduser1 · Feb 20, 2016

Black 02 said:
I was doing some extensive google searching and came across an old thread on the nation. I found a picture of some twin plumbing. Mine is plumbed exactly like this picture.

I found somewhere this is wrong and the IPR should be plumbed into the middle port so it dumps into the "standpipe" and not the right port.

Is that correct?

Dumping it down the standpipe would be better than running hot, aerated oil back through the injectors.

Black 02 · Feb 21, 2016

Long story short, I can add more detail later.

Moving the IPR dump to the standpipe location did absolutely nothing to fix my problem.

I did notice that if I unhoook the ICP sensor, the surge/miss/hitching is almost gone. The injectors make a lot more noise, but the miss is extremely faint compared to when running g-head or swamp's tunes.

mandkole · Feb 22, 2016

Im not familiar with dual pumps, but if one pump is supplying one bank and one supplying the other (based on the pictures), IPR control is lost and what you're describing makes sense.

Am I understanding this right?

Black 02 · Feb 22, 2016

mandkole said:
Im not familiar with dual pumps, but if one pump is supplying one bank and one supplying the other (based on the pictures), IPR control is lost and what you're describing makes sense.

Am I understanding this right?

I'll be the first to admit that I'm not the smartest with these things. I've learned a ton over the years, but there are a lot of smarter people than me modding these old engines.

One pump is plumbed to one bank and one pump is plumbed to the other bank. I have a HPO crossover also to help balance that out, hopefully. That being said, I don't know much more about the pumps than that. I'd pull them and send them to Joey for inspection, but he's apparently on the moon or Mars now. I also don't want to wait one year like Layson mentioned.

All I know is that I drove to work today on Swamp's trial tune he gave me with the ICP sensor unplugged, the truck didn't miss/hitch once noticabley. There might have been an extremely subtle surge around that 1750 RPM mark, but it drove very nice.

So, something the computer is over-riding when the sensor is unhooked is the culprit. If ICP is the only thing that get's over ridden, does that mean that either my HPOP or my injectors are the problem since I've replaced the IPR, the ICP sensor and all of the corresponding connectors?

I should say, the only thing different between the picture above and my setup is that the driver's side bank is plumbed in the head port next to the ICP sensor, not back by the rear of the head as shown above.

superpsd · Feb 22, 2016

I probably has no bearing as pressure in all theory is pressure but having the hpop feed the oil rail next to the ICP sensor may be giving it an turbulent signal. Maybe re plumb the line to the other port and see if it makes a difference.

mandkole · Feb 22, 2016

^^ with an HPO crossover, Id agree.

Black 02 · Feb 22, 2016

mandkole said:
^^ with an HPO crossover, Id agree.

With a crossover, you agree that I should move the feed or you agree that it shouldn't matter.

I just wanted to be clear.

Thanks to everyone for their help. I appreciate this very much.

Jessy7.3 · Feb 24, 2016

I know my truck had a rough idle when the icp was on its way out but my truck did the opposite of yours, it would run rough when the truck was cold and it would warm up, CEL would go away and it would run nice and smooth. I'm wondering if there is not an issue with a wire between the Pcm and icp sensor. You could use an ohmmeter at the pcm and go off of the pins for the icp. Have the batteries unplugged, and put a jumper between the signal and signal return and it should read near 0 ohms. Also make sure to discharge the static electricity from your body before touching the Pcm. Or if you wanted better accuracy to see if your having a loss in the wires is to find the right wires at the Pcm that go to the icp and watch for "voltage drop" across the wire but batteries need to be plugged in and and probably have to be running in order to make a voltage drop test. It really seems like a icp problem too me. I know my one guy who had a terrible miss problem but his was all the time and not hot or cold. Turns out it was just the connector had pins that weren't making a good connection at the icp.

Sent from my iPad using Tapatalk

mandkole · Feb 24, 2016

I haven't had a solution to this so I haven't said much. To the comment above, its seemed to be electrical or the two IPRs are in conflict. Ive heard of dual IPR kits with issues before.

did you swap the sensor?

Black 02 · Feb 24, 2016

mandkole said:
I haven't had a solution to this so I haven't said much. To the comment above, its seemed to be electrical or the two IPRs are in conflict. Ive heard of dual IPR kits with issues before.

did you swap the sensor?

There has been a lot of back and forth on this, so I'll try to summarize. I feel we are narrowing in on a problem, hopefully! So frustrating when you spend this kind of money and have the truck run like chit.

1). The truck has (1) IPR. I have replaced it with a new Ford replacement. Also replaced the IPR connector to be sure. Still has the issue

2). I have replaced the ICP sensor twice in 3000 miles along with the ICP connector to be sure. Used Ford parts. Still has the issue.

3). I have replaced the UVC harness and gasket with Ford parts. Still has the issue.

4). Replaced the cam sensor twice with Ford replacements and even threw in an old black one for giggles. Still has the issue.

5). Using g-head tunes. Had the issue. IPR duty cycle keeps spiking when the engine is over 2000 RPM while the ICP stays constant until DC gets above 80% and then the ICP slams to over 3500 psi. Truck also misses in the 1500 to 2200 RPM range. Swamps calls the miss "hitching". I've posted several videos. Throwing P1211 code every time the truck gets over around 2000 RPM for very long.

6). Swamps sent me a trial tune with some tweaks to try out. Still had the issue. No P1211 code from Swamps.

7). Truck coughs a little when cold on startup and has a mediocre miss. More pronounced miss at idle when the truck is warm. Sounds almost like a gas engine with bad points. Smooth and then just a quick misfire and then smooth. When engine has been run longer the 30 min, the idle almost has a subtle romp to it. Truck kind of did this on the previous motor when I first got the twins and the 350/200's. Maybe it's one of those two items causing my issues.

8). The miss/hitch only occurs after the truck warms up. Worst RPM for the problem is cruising steady at 1750 RPM on the freeway.

9). Just found out today that when I unhook the ICP sensor, the truck runs pretty good. Still has a little bit of a choppy idle, but on the Swamp's tune, there isn't any noticeable hitch/miss when driving. Truck has good power throughout the power band. Miss/hitch still occurs with the g-head tunes with the ICP sensor unhooked, but not as bad as when the ICP sensor is hooked up.

I think this summarizes things. I'm driving it now with the ICP sensor unhooked. Drives pretty decent. G-head says the ICP spike graph that I showed can't happen. Either the ICP signal is bad or the oil is aerated.

Only things left causing the issue that I think can be related are.

Oil type
Injectors
Terminator Twins
IDM?

The issue is more pronounced when the truck is warmed up. Seems like anything above an oil temp of 185 degrees.

golfer suggested I find a stock HPOP and try it and see if the HPOP is the problem. I guess I need to do that now since I don't have one to use currently.

Layson · Feb 24, 2016

Have you ran this twin pump setup with no issues prior? Is this a new setup?

Do you have a stock pump you can throw in to rule out the pumps.

Jessy7.3 · Feb 24, 2016

mandkole said:
I haven't had a solution to this so I haven't said much. To the comment above, its seemed to be electrical or the two IPRs are in conflict. Ive heard of dual IPR kits with issues before.

did you swap the sensor?

On my truck the sensor itself had a leak and oil was all over the pigtail and in the valley with easily noticeable oil tracks from where the icp plugs in. On the other truck I e encountered icp issues with, it was not the wiring itself, the the male end of the plug had bent guts so the connection was bad, they weren't even that bad but it still was enough to make a bad signal to the pcm. I was thinking that because he's replaced the connection I'm assuming at the icp but not clear back to the pcm, I was hopping to narrow it down to a wire that's messing up the signal. He said he used a brand new icp from ford, so that's good. Next he's got a new pigtail at least on there. I was just trying to narrow down possibilities with the tests is all. Honestly though, I think his best shot is in figuring out some businesses with the hpop in some form. I just wanna narrow it down is all. I of course can't say that I know the answer but the more tests he makes, the more he proves is not broken and he seems to have it narrowed down well now so I was agreeing on his truck running better with an unplugged icp would make sense because of the fail safes built in that would allow the narrowing of problems. Because of him figuring out that his truck runs better on an unplugged icp then in that case it's almost very likely that it's oil or fuel based and not a problem with the camshaft sensor. I also am thinking that it's not the idm because of the cam sensor basing its timing from that cam sensor but that's just my thought process. I hope the issue is found soon because this is a long on going problem.

superpsd · Feb 24, 2016

Did you try moving the feed. It Mau be a long shot but its not to hard to try. I use to work on hydraulic test benches with particle countering equiptment . We had to plumb in the sampling tubes correctly as there is a lot of turbulence in hydraulic systems and if you didn't put the sampling inlets in the right area you got inaccurate information. I am pretty sure all the factory setups place the feed on that side with the ICP to the rear port. They may have done this for a reason. Just a thought. It still does not make sense of the spike however so testing a stock hoop is probably what you will have to do.

Black 02 · Feb 24, 2016

Layson said:
Have you ran this twin pump setup with no issues prior? Is this a new setup?

Do you have a stock pump you can throw in to rule out the pumps.

I ran the twin pumps with the 350/200 injectors for about 3 months in 2014. I had an engine built back then by RPM Northwest in Ridgefield, WA after my PMR motor died and they screwed me over and it blew up after 3500 miles and wouldn't stand behind their work. Rod bearings were toast and I found used parts were installed where new parts were supposed to be used. Extremely long story that has been documented on the army.

Long story short, I got about 3500 miles previously using DP's tunes and added a Swamps IDM. Truck ran pretty good but had a similar issue at mid-rpm cruising. Also had the smokey startup and sometimes choppy idle. Never got a chance to work the bugs out before the engine died.

So..... I've never had this setup run great in my truck. I sent the injectors back to Full Force back in 2014 to try and figure out the bad idle and smokey start up. They looked them over supposedly and said they were fine. Put them back in it and it still did it. The hitching/miss wasn't as bad, but it was still unsmooth when cruising around 1500-2000 rpm. I sent them back again for them to go through them after the other engine blew just to make sure they were ok and they sent them back and said they were fine.

Switched to g-head tunes and put this setup in the truck for a second time and now I'm having these issues. The only thing carrying over from the previous engine is the injectors and the HPOP system. Everything else has been replaced or is new.

Lastly, I do not have an HPOP to use. I sold my T-500 and the guy never sent me the core he was supposed to send me. I have an old OBS HPOP, but it sat outside on a wrecking yard motor for a couple years, so I don't really trust it.