In article
.com>,
wrote:

> Can someone please help me figure this out? I am really stuck.
>
> I have a 1995 CHEVROLET TRUCK ASTRO VAN 2WD
> 6 Cylinders 262 W 4.3L CPI. 105,000 miles
>
>
>
> Symptoms:
> The van is cutting out like it is running out of fuel while driving.
>
> I let the van warm up first before a test drive. It drives okay (not
> great) at first, then it starts acting like it is running out of gas.
> It bogs down and stalls when I accelerate. I tried flooring it and it
> wants to die. This problem is progressive meaning it is getting worse;
> now it happens after just a couple miles of driving. The problem will
> go away (van drives much better) after turning off the van and then
> back on.
>
>
> History:
> Fuel pump quit working over new years. I replaced and it drove fine.
> I drove one 300 mile trip then another 300 miles of city driving with
> no problems.
>
> It got real cold (irrelevant?). I drove for 25 miles with no issues.
> I filled up with gas (irrelevant?) after work and drove 10 miles and it
> started acting up.
>
> The problem got worse over the next couple days (60 miles city
> driving).
>
> I changed the fuel filter which was clogged and appeared to be the
> original filter. It seemed to run fine. I drove several very short
> trips 5 miles which may have been too short to notice symptoms. I
> filled up again, then drove 15 miles.
>
> It acted worse than ever.
>
> I checked the fuel pressure. It was about 62psi with the pump running
> but dropped to 6psi when not running.
>
> I replaced the CPI unit and the nut kit (fuel lines). The fuel
> regulator was leaking. I could see where the gas had cleaned the
> inside of the plenum.
>
> I retested fuel pressure. It was 62psi with the pump running but
> dropped to 22psi with the pump off. My Haynes manual said it should
> only drop 3-10psi with the key off.
>
> I road tested the van and it has the same symptoms.
>
> Shouldn't I be able to see or smell the gas that bleeds off? I
> don't see any gas (I will double check tonight).
>
> Now I do not know what to do. I am stuck. Can anyone offer any
> suggestion?

You need to determine if this thing is going too rich or too
lean when it acts up. Ideally, a test drive with a scan tool
installed so you can view O2 sensor volts and the fuel trim
numbers. Plug color and watching the O2 sensor on a DVOM is a
do-able method if you don't have a scan tool.

The fuel pressure shouldn't drop off as it does, weak pumps
and/or a failed pulsator usually manifest themselves as hard
starting after an overnight set. Entirely possible that it's the
CPI and regulator (again), who did you get those components from?

Did you re-use the old pulsator when you changed out the pump?
Pulsator = the oval shaped piece that connects the fuel pump
outlet to the sending unit , black plastic with a stamped tin
cover.