Another possible fuel pump thread?

[gn87turbo]

Here's the history with my current miss/hesitation. Bought the car about 2 months ago and it ran smooth and great. Took it to the track about a month ago and on my way to the track ran the car out of gas so I could put in the 110. Car seemed to run fine that night at the track but on the way home I noticed a slight miss/hesitation under mid boost(8-10). WOT at times is fine and daily driving is fine. I've noticed my blm's are now high and yesterday they would bounce from 128 to 139 back and forth with no in between numbers. If I let the car sit after setting my fuel pressure at 43 lbs. vacum off, at times the fuel pressure will read 5-10 lbs. higher or lower and I will have to re-adjust the pressure again. Also, my 02 numbers are not consistant. I can take the car out and for 2 WOT runs o2's will be in the 750's for one and 620's for the other with no changes. The other day I went out and could not get the car to boost up, it would get to around 10-12 and thats it. Let it sit for several hours went back out and it seemed ok but still had the hesitation under mid boost. I can't seem to get my o2 numbers any higher than that. I now have the tank down and pump out hoping it was the fuel sock but its fine. Does this sound like another Walbro 340 failing? Just wanted some advice before I order a new pump.
Thanks,
Patrick

 

[Junior Samples]

ran the car out of gas so I could put in the 110.

Ran it completly out, as in sucking it dry? or down to a 1/4 tank or so?..just curious

 

[Just a Six??]

If you ran it DRY then thats not a good idea! Your filter is probably partially clogged from that. Change that first.

 

[gn87turbo]

I did run it completely out. I changed the filter and that did not help. Did I damage my pump running it out of gas?

 

[Chazzworth]

I did run it completely out. I changed the filter and that did not help. Did I damage my pump running it out of gas?

I would guess yes the the fuel does help cool the pump.

 

[whitehot1]

Another thing could be the fuel sock / filter on the end of the fuel pump could have collapsed, i have heard of this happening and may be worth checking it out.

I have never seen it happen personally,but i've never ran or seen a pump after it had been run dry before.

 

[87GN_70GS]

What is your fuel pressure at WOT?

 

[gn87turbo]

When I ran it out of gas, I was on my way to the track and when the car started loosing fuel pressure I immediately pulled off and put in the 110. I have a Kenne Bell hood mounted guage and it seems that my pressure will get up around 60 but when I've noticed the miss it seems that the pressure will bounce a little.

 

[gn87turbo]

Would a damaged pump cause the blm's to run a little high and bounce around like I described? Would it cause the mid boost hesitation/sputtering I described and the inconsistant o2 #'s?

 

[turbot990]

here is what we used a 1996 s10 blazer vorteck 4.3 6 cylinder w is the 8th digit in the vin number it works we put one in my friends car he ran a 12.90s with street tires with 15psi 02s were good and the car ran clean all the way threw the 1/4 mile at 111.00 mph .

 

[gn87turbo]

Anyone had a problem with a fuel pump similar to this? I just want to make sure before I get a new pump and install.