B190 Enthusiasts

Hi to all.
Anybody had a problem similar to this, if so could you give me your ideas as to what may be wrong. In preparation for taking my Mother (89) on a trip to see her brothers (97 & 83) we thought it would be a good idea to see if she could handle the ride so we went for a short drive of about 240 miles round trip.
Before leaving I topped of both tanks so there was plenty of fuel. The front tank sending unit on the fuel tank pooped out so it was not working, I used the front tank figureing that when or if I ran out of gas I would switch over to the rear. I used the coach air and generator for part of the drive just to check it out and it worked just fine, in fact had to shut it down because it got to cool for my mother even though the day turned out to be a record 90 degrees.
About 8 miles from our destination, the van just lost power and would not run so I figured the tank had run out and switched over but it still would not start so I had to pull over and stop.(bathroom break for the wife and mother). After turning the ignition on and off a few cycles for the pump to charge up, the van started right up and we got to our destination where I went to a station to fill up.
The rear tank took less then a gallon and the front tank took less than eight gallons which was a relief in one way knowing that my milage was around 15 at 70mph, even with the coach air on. My problem is why did it quit. I am thinking that maybe something got sucked up from the tank but with new fuel pumps installed before purchase and it running like a charm on the second tank that that is not the case. It can't be a vapor lock I don't think because it is fuel injected so if there are any ideas out there, thank you in advance.
Sorry for the length and proud to be a member.
Craig

My vehicle is a 1991 with duel fuel tanks(41 gal)

Ooh, that's a good one.

First, I've accidentally run a tank dry on several occasions and have switched to the other tank at speed without a problem (other than stuttering because the engine has no fuel for a moment). So I think you're right on the vapor lock part.

I took a look at my Chiltons and don't see anything definitive. However, I would suspect the "switching valve" (or whatever it's called) that lets us switch between tanks, or the air bypass. I know that's not much help...

Just an update on my previously described fuel problem. As you can read from the above problem, I was perplexed as to what was wrong and did not think that a fuel pump was a problem because the dealer had told me and also showed the receipts for new fuel pumps in both tanks. The mechanic I took the van to did a pressure check and it came up negative but after experiencing the same problem again and holding up traffic, I took the van into the shop and had them replace the fuel pump.
Problem solved.. If I can figure out how to post a picture I will post one of the pump and assembly. Buyer Beware.. The so-called new pump that the dealer thought was new was just a peice of crap. The float unit was covered in somekind of plastic filler (I assume to plug a hole in the float as it was dripping fuel) and I guess the weight caused the sender to always show the tank was empty. Bare wires twisted together which I guess as long as they were coverd by fuel posed no problem and overall the whole assembly was junk.
The van now runs like a charm on both tanks, so if there is a fuel problem and everything else checks out, I would say to check the fuel pump, a somewhat expensive fix but now I have peace of mind.

Also check out the plumbing forum, for a water pump issue and fix that I just resolved.
Craig

I had the same type of problem a short time ago. Rig would run fine when first fired up but after 40 miles or so of hard running on warm days it would quit. I checked electrical first including the pcm but no problems so I put a fuel pressure gauge on it. When first started it carried 50+ psi. but after about 40 miles on a 80+ day the pressure started falling. After falling below 10 psi it quit. Also I noticed preignition was starting to be a problem. I changed the pump and solved both problems and it seems to have more power.