Ford F250 1999 Super Duty 7.3. Engine light and battery light came on. The truck lost power momentarily last week but didnt die - happened just once. I plugged in the computer and the only errors were on the glowplugs bank 1 and 2. I decided to change the glow plugs myself starting with the drivers side. There was nothing to difficult about this. I was planning on changing the passenger side glow plugs this weekend but then a mechanic friend told me that sometimes a bad relay will cause a GP error on 1 and 2, so knowing that the GPRs are known to fail, I decided to play it safe and replaced the relay. As luck would have it the GP 1 error disappeared. Then out of nowhere the truck started blowing white smoke and vibrating on startup. The oil is clean, the truck is not overheating and all dials are normal. That being said, the computer is now showing a dead bank on 6 and 8 which were the last 2 glow plugs I put in. The only thing weird about the GP change was that my socket wrench kept getting stuck so I loosened (did not remove) the rocker arm pedastal bolts to the right of the GP so that my wrench could reach, remove and tighten the new GPs. I did retighten the rocker arm pedastal bolts. Granted Im not a mechanic by trade, but Ive worked on my own vehicles for 20+ years and new or old, if you mess up in the engine the problem is generally apparent immediately - not 24 hours later. So now Im wondering if I could be dealing with a bad or loose harness. I doubt its just a coincidence that banks 6 and 8 are now dead banks when the last 2 GPs I installed are in banks 6 and 8

 

Welcome to FTE. I guess you have a CA emissions vehicle to get the glow plug codes? What are you using to pull the codes and what codes are you getting? Can you monitor any live data with your scanner? A loose wiring harness is a common issue on the 7.3 motor. Scroll down further to the 99 - 03 7.3 diesel section and you can search for the 50 cent mod or you can buy shims to keep the connector from coming unplugged. It's also not unheard of to knock an injector plug loose when putting the valve covers back on.

A couple of other things to bring up. Hopefully you did not use Autolite glow plugs. The tips of those have been known to swell up so you can't remove them later. Motorcraft brand plugs don't have that problem. Rocker arm pedestal bolts should be torqued to 20 ft lbs. If they're a little off, that won't be causing your problem, but it's just general info. Next time you replace the glow plugs, break it loose with your socket, then shove a rubber hose over the tip of the glow plug and you can use that to unscrew and remove the glow plug from the hole without having to touch the rockers.

 

Moved to the 1999 - 2003 7.3L Power Stroke Diesel forum.

 

Well it wasnt to hard to spot the problem when I opened the valve cover. The rocker arm pedastal bolts that I loosened for banks 6 and 8 went back down tight but apparently not tight enough. The pedastals were almost completely off. I know they went down tight, so there must be a trick to this. I went ahead and finishing removing the pedastals to see if anything else had been done, but theres nothing out of place - thank god. The pedastals sit on a free standing rod on the top side. The rod just falls into a hole and acts as leverage, but Ive been trying to put the darn pedastals back and the rod seems to force the pedastal to sit higher then the mount.