My other truck (the ford) has started something new. When the motor is cold it will lope really bad, excessive fuel smoke and just hammer. The check engine light will come on. Once it is warm it will run just fine, no more light, smoke or knock. Then for the rest of the day it's fine. Now I did have cenex synth blend in the truck. I know they say fmc oil only so I dropped that and filled back up with the right oiland new filter. No change. Now I took the hypertech off, it is better, but still has the same symtoms as before just not as pronounced. I thought fuel so fueled up the front tank and used additive, still no change. I had to pull a load of firewood today so I put the program back in, (got used the the extra power) It runs just like a champ. But tomorrow it will be the same deal lope smoke light. (btw the dodge has campershell on it with my dj equipment in it for a dance tonight so had to drive her furd) My programmer didn't pick up any codes, and the light doesn't stay on. Any idea's????? I rebuilt the motor only has 3400 miles on it.

 

well seein that your in colorado and it gets kinda cold there, would guess your glow plugs are gettin weak, so its havin to warm its self up. thats my guess.

 

I thought the 7.3 liter Fords were known for hard starting and having glow plug relay and glow plug problems. I think the the glow plug relay looks like a Ford starter solenoid. You should be able to have the local parts store order you one.

I know two guys with 7.3 Fords. Both of them had no starts and had to change the relay/solenoid.
Good luck

 

The seloniod was new when I rebuilt the motor this summer. The first time it did it it was only 20 degrees out, but it was plugged in. The seloniod seems to be working, it clicks and pulls the volt meter down. Is there a way to check for codes without taking it to the shop? And I'm not sure it set a code because the check engine light doesn't stay on.

 

I think that you should stay with the glow plug suggestion , theres a couple test , 1st is a ohms test , diconnect and check each one [ sorry don't remember the spec.] it may be just one , you do not have to replace as a set , next is if you have access to a amp meter that can handle the load [ again no spec.] then if you still have a prob. go to one of the do it yourself parts houses they can pull some basic codes , with the lite going out that means its a soft code -prob. goes away vs, hard code that is always there or can couse damage.

 

glow plugs on a 7.3 it should come with ur manual "warning glow plugs on ford diesels will take a dump when u need them"

 

I know on the IDI Fords you could use a testlight to check the glowplugs.
I don't know about the older powerstrokes. I remember some high voltage wiring under the hood tho.

 

IF the truck is loping,

and its not the glow plugs, what about the HPOP? i know that these trucks run their injectors on the oil pump or something similar?

Might wanna try that

Tx

 

That's why i dropped the oil, I was afraid the cenex was causing a problem. I visited with wife this afternoon. Whish I would have talked to her earlier, she said she has had to cycle the glow plugs about 3 times for the last month. (she only said something when the check engine light came on)

Anyhow, I hate the thought of having to remove the valve covers on the 7.3 to check each of the glow plugs. Any ideas on a check from the outside????

I really hope its not the high pressure pump.

 

Your injectors are shot. Not enough clearance between the armature and the injector body. With cold oil they don't shut off properly, thus the smoke and knocking. Once the oil warms up they are OK.

 

It sounds like an oil pressure issue or injector. If it was a glowplug you would have hard starts, truck wouldn't start and then lope. Glowplugs aren't like are grid heaters that keep cycling on/off when cold. Glowplugs just pre-heat the chamber and then shut-off.

 

The injectors are shot.

The check engine light is coming on because the ECM has the duration cut to nothing and still can't keep the engine under control. The lope is happening because the ECM is shutting off injectors entirely to keep the engine under control. The smoke happens because the injectors won't shut off properly when the oil is cold (thick.)

The ECM may be giving a high side open error. It is a false error. There is nothing wrong with the high side circuit.

The injectors are shot.

It has nothing to do with the glowplugs. Glowplugs don't cause loping. If the glowplugs weren't working the engine wouldn't start below freezing. Most won't anyway.

 

Superduty,

Thats really not what I wanted to hear. I kind of wondered about the injectors ever since I put them in. They are the originals w/175000 on them. The truck runs great other than just first start of the day, even when it has been shut off for all day. I think the heads hold about 3 quarts of oil above the 14 quarts that the pan and filter hold. Could the synthetic still be causing a problem? That stuff was like pouring honey when its cold, and I know that it isn't all out of the motor yet. The truck seems to "load up" when putting around town today. I'm probably dreaming though. Has anyone rebuilt HEUI injectors? They are awfully proud of the dang things.

 

I agree with Superduty about the injectors. Luckily, there are now some rebuilt ones on the market. I've installed them in several trucks and they have worked well.

 

"The truck runs great other than just first start of the day, even when it has been shut off for all day."

It is warmer later in the day and once the engine is warmed up in the morning, it takes a long time for the oil to get cold again. You might have a cracked pick up tube for the oil pump, but I doubt it as then it would hard start when hot.

"I think the heads hold about 3 quarts of oil above the 14 quarts that the pan and filter hold."

The heads hold about 3 cups of oil each. 750cc.

"Could the synthetic still be causing a problem? That stuff was like pouring honey when its cold, and I know that it isn't all out of the motor yet."

I doubt it. Powerstrokes run poorly when really cold anyway. Try plugging the block heater in and see if that makes a difference in the smoke, romping and check engine light. If it does, it is almost surely that the injectors are shot in that they can't handle thick engine oil anymore.

You could pull the valve covers and pull the injector solenoids off and then slide feeler guages under the armatures. You need 4 thou or more.

"The truck seems to "load up" when putting around town today. I'm probably dreaming though."

Probably not. With that kind of mileage the nozzles are shot too.

"Has anyone rebuilt HEUI injectors? They are awfully proud of the dang things."

You can't rebuild them without a lot of knowledge and equipment. People do it, but that is another story.