Low Boost / Power - Water in Fuel Light - Diesel Forum

Hawthorne · 08-07-2006, 06:21 PM

Intermittently the engine stumbles or dies completely -- the coil and water/fuel light come on. This happens sitting in my driveway as well as under heavy load. If the engine dies completely, I can put the clutch to the floor, restart, and pull away normally. If the engine only stumbles, it will not make normal power until the clutch is depressed and RPMs allowed to drop to idle; then release clutch and power returns to normal. On third EGR value, but no smoke this time. Took into Ford. No codes. Service drained the HFCM, did lube, oil, fuel filters, etc. Had them install boost and EGT gauges.

Thought all was well, then had the stall/lights return last week. Power seemed low, but it's hard to make a long unloaded full throttle run. Towed my 4000lb boat over Mt Hood this weekend...slowly. I usually have to check and make sure it's there. Truck wouldn't make more than 6 psi at any RPM. Power is way down. Turbo whistle is non-existent. EGTs were 10-11K @ 3600 RPM.

Back to Ford this Wednesday. Any ideas how to describe to the tech? What if there are no codes? I buy fuel at Pacific Pride exclusively. How do I get ready for the "you buy bad fuel" excuse? Let them clean/rebuild turbo, or replace?

GregH · 08-07-2006, 07:46 PM

If the glow plug (coil) light and WIF light both come on during an event in the engine, it is caused by a PCM reset. No codes would be stored, since the PCM momentarily stops working. The likely cause is a wiring harness problem on the engine. Unfortunately, the only repair authorized by ford is a replacement of one or both harnesses.

Places to look at while the engine is running is the harness where is goes under the air intake tube near the turbo, the little bridge between the oil fitler housing and the fuel filter housing, the harness where it dives down the front of the motor near the thermostat, and on the other side under the alternator. Push on the harness from various angles with the plastic end of a screwdriver while the engine is idling until you find an area that - when disturbed - will kill the engine. Of course, be careful when you're near a running engine.

Good luck.

timeforadmax · 08-07-2006, 10:57 PM

My truck has been doing the same thing, so far we have replaced the fuel pump, egr valve, and the injector control module. The last two times they have not found anything wrong with it, it showed no codes, I am going to take it to another dealer and the service manager told me it is more than likely the wiring harness.

Hawthorne · 08-16-2006, 04:26 PM

So I'm getting my Truck back from Ford today. Thanks GregH, I had found the short before I took it in. It was near the EGR; I found by your screwdriver method. Then discovered that disconnecting then reconnecting the EGR with a cycle of the key between restored some boost until the next water/fuel light shutdown. Under the $100 deduct powertrain warrantee they have done the following.

To correct Water / Fuel light shutdown:
Both Engine Harnesses Replaced

To correct low boost:
New PCM Unit - tech said short had fried the old.
Replaced a couple of bellows clamps and tightened both sides of turbo / induction system.

Just thought others w/ simmilar might be interested.