Posted on November 6, 2009 - by Richard

Another Salvage Yard Tip: Fix 1999 Ford Explorer Won’t Start

How do you Fix 1999 Ford Explorer won’t start? The engine is a 4.0L and has a lot of miles. A mechanic friend had been checking this truck with a weird symptoms:

1.) It won’t start and stay running unless you remove the mass sensor. It then runs but has a rough idle

2.) When scanned for codes, has a fault code P0300 or random misfire.

Diagnostics to fix 1999 Ford Explorer won’t start:

We started the troubleshooting by wiggling the mass sensor wires with engine running. Hope to see any rpm change because some other garages reported a short to the mass sensor circuit. No rpm change.

Removed the vacuum hose off the brake booster cylinder so that we can measure the engine vacuum pressure reading. I wanted to establish if the the fix for this 1999 Ford Explorer won’t start is caused by an engine vacuum leak. These were our findings:

Vacuum needle does not oscilliate which to me means the cylinder head and compression chamber is OK.

Vacuum reading sat at 6 inched Hg at idle which is way below normal of 17-20 inches hg.

Solution to the Fix 1999 Ford Explorer won’t start:

Using a bottled water with a spray mist, we spray on top of the engine manifold of while idling. When the spray was directed at the top upper manifold on the driver side, rpm changed accompanied by a hissing sound. Removed the egr DPFE valve to get a closer look, we found a big crack on the side of the upper intake manifold. The crack was caused by heat made by the egr tube beside it.

Quick tips on Fix 1999 Ford Explorer Won’t Start:

1.) The parts cost to Fix 1999 Ford Explorer won’t start is almost the cost of the truck itself if you call the Ford dealer. However, in a short trip to the salvage yard, we found the parts and bought them at almost 1/10th of the cost. You can do it if you pull the part yourself. Some used parts store store will charge 50 to 75 percent if you buy it from the counter. And if you do the job yourself, you can really do it really cheap.
2.) No money? No problem…Put a glue to seal the intake manifold crack and it should be good for a few months!

Thanks!