No start cold unless plugged in block heater
<hr style="color:#ffffff; background-color:#ffffff" size="1"> Guys,

Could use some help here. I can not get my 1996 F350 7.3 (Just purchased) to start when cold.
-Relplaced glow plugs with Beru/Motorcraft ones
-Replace the valve cover gasket with wiring harness.
-Replaced ICP sensor.
-Cleaned EBPV - NO more codes on this item.
-Replaced fuel filter
-Changed oil - Rotella (same as I used to use in my 99 powerstroke)
-Thrown tools/adverbs etc. Drank beer in can still no progress

A few frustrating things was when I replaced the valve cover gasket and harness and had a very hard start when plugged in. I traced that down to a bad harness when torqued down (They were brand new!)

I ohm'd the new glow plugs at the connector coming out of the valve cover and will not ohm through the (5 prong plug) center ground. Will ohm when touched to engine lift ring etc. I believe that is normal. The injectors ohm through plug though.

Jumped the relay with jumper cables (both large terminals) and still no start. I checked with the key on and I have power to the plug at the harness on the valve cover for approximately 50 seconds. Forget how much voltage.

The wait to start light only stays on for less than 10 seconds in under 30-40 degree ambient temps. Normal?

Batteries are fully charged and on a charger for a boost to help along in case they run low.

I replaced the ICP and it starts now in around an hour instead of 2-3 hours when plugged in.

I have an AE scan tool. The 3 minute 3300 RPM test leaves me from 1397-1420 on the ICP with a 10.94% duty cycle.
At idle 574 ICP/11.33% Duty cycle
EBPV 13.88 MAP 12.8 no boost at idle.
Cylinder contribution test pass.
KOER test pass

The only issue is the no start cold. It sounds like about half the engine is trying to start. Once plugged in it fires right up. The longer it is plugged in the less smoke or the warmer ambient temp the less smoke. It sounds like the Relay is working (checked at terminal on relay and plug to harness) and new glow plugs.

One more thing. I pulled the valve cover again and connected one glow plug and energized it. Did not get hot. Tried to ground to engine with jumper and still not getting hot. Is this a legitimate test for the glow plug or would a good one not work not plugged into the engine?

Any ideas would be greatly appreciated. I have a lot of tools in the yard to pick up....

 

Are you getting voltage to the plug at the valve cover?

 

Yes, Voltage at plug at valve cover, can not remember the amount - assume batt volt.

 

Are you sure you had good contact on jumping the relay ?

 

Just a WAG ... It may be a poppet issue ...

You will need to pull the covers and observe the injector spill spouts ...when cold ...

 

I tested the relay by seeing if there was voltage (batt volt) at the terminal going to the glow plugs. I believe I had the same amount on the battery side and glow plug side for about 50 seconds. Then I took jumper cables and red cable to one side and red cable to the other just to rule out the relay entirely. Still no dice. I have power to the valve cover and resistance from the valve cover to ground for the glow plug.

I disconnected the glow plug from the engine and let it suspend in air while connected to the gpr and harness etc. I grounded the threads to a engine ground (maybe not grounded well?) and the glow plug did not get hot when turned on. I believe it should have. I can't believe all 8 glow plugs would be bad as they are brand new.

 

Check the voltage coming out the GPR it should be within 1 volt of batteries

 

I am sure I had good contact on jumping the relay. Poppet issue. Not sure what you mean. I assume it is a oil issue to the injector? If when I crank the engine cold and oil comes out it is good, very little bad? Could you explain more?

 

Any smoke while cranking? And how is hot starting?

 

Also, I checked the oil level in the front cover. I filled it to the top and let it sit for 3 days. The level dropped to 1/2" from the top of the plug after 2 days and stayed there. I heard something about a oil drain back issue or something and was told to check that out. Haven't read that anywhere on here though.

 

It should stay about a half inch from the top

 

Whitish and fuel smelling smoke when cranking cold. Once it is plugged in fires right up with no problems. Also on cold start the icp and duty cycle appear normal and then after a try icp goes through the roof. Assume it is the computer throwing everything at the beast to get it to fire.

 

WOW, Thanks for all the quick replys. Got lots of beer if any one is near carson city. A drunk smart guy can't do any worse than a sober dump guy on this!!!!

 

When it's cold how does the engine spin? These motors need to spin nice and quick to fire

 

Sounds like a gp problem then. I'd in hook both small wires from the relay. Hook one to ground and one to power. See if the relay clicks. also what part number relay did you get. Try and put a screwdriver across both big termanils as well for 45 seconds and then jump in to start it.