Bad injectors?

Gootee · Mar 31, 2014

Trying to hunt down what's going on with my truck after it's been running rough. I replaced the uvch's and didn't solve the problem. Checked codes again and got the following.
P1316 idm codes detected
p1275 cyl. 5 high to low side open
p1278 cyl. 8 high to low side open
p1298 idm fault

Also replaced the idm with a hvhf model from swamps. Any idea guys? I'd really like to get this thing figured out. Thank you!

MAFoElffen · Mar 31, 2014

Have you checked the injector coil resistance at the IDM connector yet? If not, I'll post GB's tech bulletin #103 or you can Google it. Just to rule out it being electrical.

Other would be to use an IR temp gauge. Take cold reading at each of the exhaust ports cold. Start it up and let it warn up as you keep taking readinds. Weak cylinders will not heat up as fast.

Next would be to pull the covers and do a manual CCT. Start it up. Visually check the oil squirting under the deflector to ensure all are pumpimg the same amount of oil. Then disconnect and reconnect each injector and each should fall in RPM evenly.

Those are just things you can do without an OBS scan gauge.

Easier would be to look at live data.

Gootee · Apr 1, 2014

No I haven't tried yet. Well what kind of data are we talking about here? I've got access to a snap on scanner but all I looked into was the ipr and icp. Both seemed to check out okay

MAFoElffen · Apr 1, 2014

Gootee said:
No I haven't tried yet. Well what kind of data are we talking about here? I've got access to a snap on scanner but all I looked into was the ipr and icp. Both seemed to check out okay

I have AE on my laptop and Car Gauge Pro on my Android phone. On both I can run CCT's and a Buzz test.

That code is usually either a bad injector coil or injector wiring. The wiring is usually the connectors under the valve covers, a corroded terminal at the outside of the vavle cover connector or a bad valve cover gasket (the connectors/wires go through them). You can check all that doing that resistance check with a VOM at the IDM connector:
https://www.google.com/url?sa=t&rct...Gefyejf-zZofSgZyks-dMJg&bvm=bv.63934634,d.aWc

What is a little odd, is those codes usually go in adjacent pairs, for instance on the same side of the motor.. Like 1&3, 5&7, 2&4 or 6&8. But yours is on the third back on the passenger side (#5) and the furthest back on the driver's side (#8)... Any ways, that code says there is an open in the circuits for those two injectors.

I doubt is is a diode in the IDM. If one of those goes, you usually lose a whole side and you would be complaining that it is very hard to start and runs with no power.

If an injector coil is out of range (shorted or too much resistance) most people change out the injector. I usually just pop the coil off and change them out. You can confirm that it's bad and that it will function again by swapping a known good one on it (from another cyl.) and see if it comes back up. You should be able to pick a AA coil up at an injection shop for about $50 new, $20 used (tested). Lot's less than $240 for a replacement injector at Ford or $180 OEM.

Gootee · Apr 1, 2014

MAFoElffen said:
I have AE on my laptop and Car Gauge Pro on my Android phone. On both I can run CCT's and a Buzz test.

That code is usually either a bad injector coil or injector wiring. The wiring is usually the connectors under the valve covers, a corroded terminal at the outside of the vavle cover connector or a bad valve cover gasket (the connectors/wires go through them). You can check all that doing that resistance check with a VOM at the IDM connector:
https://www.google.com/url?sa=t&rct...Gefyejf-zZofSgZyks-dMJg&bvm=bv.63934634,d.aWc

What is a little odd, is those codes usually go in adjacent pairs, for instance on the same side of the motor.. Like 1&3, 5&7, 2&4 or 6&8. But yours is on the third back on the passenger side (#5) and the furthest back on the driver's side (#8)... Any ways, that code says there is an open in the circuits for those two injectors.

I doubt is is a diode in the IDM. If one of those goes, you usually lose a whole side and you would be complaining that it is very hard to start and runs with no power.

If an injector coil is out of range (shorted or too much resistance) most people change out the injector. I usually just pop the coil off and change them out. You can confirm that it's bad and that it will function again by swapping a known good one on it (from another cyl.) and see if it comes back up. You should be able to pick a AA coil up at an injection shop for about $50 new, $20 used (tested). Lot's less than $240 for a replacement injector at Ford or $180 OEM.

I'll have to run another buzz test today and post the results. I can't remember what all the injectors came back as but I do remember 5& 7 being different from the rest. I'm going to try the coils today. I'll be sure to post results of that as well. Thanks bud

MAFoElffen · Apr 1, 2014

No problem. I'm known for diagnostics. Before I invested in AE, I had to get real creative on the cheap. Now, not as full featured, but I coan do a lot of those same things from my phone and was less than $30... Have never used the Snap-On scanner, so don't know what features it has.

IPR, ICP and injector pulse width will give you good numbers on your HPOP pressures, duty cycles and to see what it thinks it needs as related to load and comparison "desired" readings... But that wasn't what your DTC's were telling you was wrong.

Instead of logic related to mechanical's, it is electrically related. That is actually a good thing, as what it said is usually easier and cheaper to fix.

That is unless you really wanted an excuse to spend more money to upgrade to bigger injectors(?)

Gootee · Apr 1, 2014

MAFoElffen said:
No problem. I'm known for diagnostics. Before I invested in AE, I had to get real creative on the cheap. Now, not as full featured, but I coan do a lot of those same things from my phone and was less than $30... Have never used the Snap-On scanner, so don't know what features it has.

IPR, ICP and injector pulse width will give you good numbers on your HPOP pressures, duty cycles and to see what it thinks it needs as related to load and comparison "desired" readings... But that wasn't what your DTC's were telling you was wrong.

Instead of logic related to mechanical's, it is electrically related. That is actually a good thing, as what it said is usually easier and cheaper to fix.

That is unless you really wanted an excuse to spend more money to upgrade to bigger injectors(?)

As far as the scanner goes it will do pretty much anyting AE will do. And I just checked the numbers out of curiosity to eliminate it being either. I wish I couldn't afford to right now, that's why I'm trying to keep things on the cheaper side! I'll be digging into it here in about an hour or so!

MAFoElffen · Apr 2, 2014

Find out anything?

Gootee · Apr 2, 2014

MAFoElffen said:
Find out anything?

No not yet. I swapped some some selonoids but didn't get to check yet I couldn't get ahold of the scanner yesterday. Should be able to today

neverkickn · Apr 2, 2014

If you have a modded idm I wouldn't put too much stock in those codes so long as the wiring circuit is good. You should check the wiring from the idm plug by testing the continuity of each injector circuit.

Have you checked the easy stuff like fuel pressure and quality?

MAFoElffen · Apr 2, 2014

neverkickn said:
If you have a modded idm I wouldn't put too much stock in those codes so long as the wiring circuit is good. You should check the wiring from the idm plug by testing the continuity of each injector circuit.

Have you checked the easy stuff like fuel pressure and quality?

You must not have read the posts(?) I already link him to a tech bulletin with all the directions for that. I think he was checking that last night...

Gootee · Apr 8, 2014

Finally got around to checking everything and it all came back at 2.7 ohms.. I'm really thinking I'm just going to replace the injectors and pray it's that. It's hard to start. Low power and is throwing codes for 5 injectors now. I don't know what else it could be

Gootee · Apr 8, 2014

Just pulled the valve covers again to check and the whole drivers side isn't shooting oil out of the deflectors so maybe idm? Also, I've tried new uvch's as well and it didn't change anything

neverkickn · Apr 8, 2014

Gootee said:
Just pulled the valve covers again to check and the whole drivers side isn't shooting oil out of the deflectors so maybe idm? Also, I've tried new uvch's as well and it didn't change anything

You mentioned you had a swamps idm is that correct? Call them and tell them what you have going on. My swamps idm will set faults on a buzz test too but so long as the truck runs right then it is not a problem.

Considering you have a dead bank and no open circuits then I would suspect the idm too.

MAFoElffen · Apr 9, 2014

neverkickn said:
You mentioned you had a swamps idm is that correct? Call them and tell them what you have going on. My swamps idm will set faults on a buzz test too but so long as the truck runs right then it is not a problem.

Considering you have a dead bank and no open circuits then I would suspect the idm too.

One or two dead, I would say other things. 4 dead, bigger problems that narrows that down. You already checked the wiring and electrical going to and from the injectors, so electrically, there are sound. Since it is the whole bank on one side, it could be one of two things...

-Check to see if you have HPOP pressure in that bank... A reading of ICP pressure is from that head... Just to ensure you don't have a leak dumping pressure in that head... That is not likely, but is good to rule out.

***More likely with all 4 injectors dead in one head would be a diode blown in the IDM. You could check if you where getting sense voltage by putting in noid lights, but since most don't have those...

I agree-- Call Swamps and tell them what is going on.