Ok, I've just had something very strange happen to my '94 Sport. My wife called and told me that it was idling very rough and it kept cutting out on her. When I cranked it to check it, it was indeed idling rough, and I could here the loud hiss of a loose vacuum line. Nothing wierd so far, right? I opened the hood and found the source of the vacuum leak. Screwed into the side of the intake (driver's side) back close to the firewall, there is what looks like a manifold for several vacuum lines. There are 4-5 different hoses that feed from this manifold. One goes to the brake booster and one goes to something that has to do with the throttle. I haven't traced the others yet. Three spickets were sitting open when I found it (hence the massive vacuum leak). The two hoses coming directly out of the rear of the manifold (toward the firewall), and one directly in front were blown off. There is also some substance, either brake fluid or oil, all over the hoses that were blown off. What the heck could have happened? I have yet to find the hose that belongs on the spicket in the front of the manifold. My hose schematic has faded beyond recognition, so I don't have anything to aid my search. Does anyone know if a hose goes on this spicket, or is it just capped off? I've replaced the two hoses in the rear and capped the one in front and everything is running fine.

I recently replaced the driver's side brake caliper. I don't know if anything could have happened during the repair that could have caused this. I used a hand vacuum pump and a siphon bottle to bleed the brakes after the repair. That's the only thing about this repair that was different from other brake repairs I've done. That's the only work that's been done on the truck lately. Two weeks and 800 miles have gone by since the repair job.

I don't have any great theories on this one yet. Any insight would be GREATLY appreciated.

Thanks,
Joel

 

You will find one of those vacuuum hoses going to the transmission modulator valve either on the side of the trans or on the rear part. Anyway remove that hose from the valve and you will notice fluid in the hose. Not supposed to be there. Replace the valve and any vacuum lines that are now to loose to say on the tee any more.


2000 XLT Flare Supercab Sport 5.4-Auto-355LS-Tow pkg-Bedrug-Xtang Tonneau

 

Good call on the transmission modulator!!! Many thanks. That's exactly what the problem is. I pulled the hose off of the modulator and had to jump out of the way of a stream of transmission fluid. I got everything disassembled last night, and I'll stick the new one in after work today.

On a side note ... COULD THEY HAVE MADE THAT THING ANY HARDER TO GET TO?!!

Thanks again,
Joel