97 LT Astro Slow start, no start

[ckmn]

Well, after doing some reading and researching on this site and a few others I believe I have a fuel problem, but I would love some other opinions... I live in Atlanta and I recently bought my second Astro w/ 104k on it out of Chicago. My first one was a 1988 model and I simply wore it out, and my new one is a 1997 model 2wd LT. I noticed that it took longer to start than my older van, maybe 1-2 seconds more of starter spin. I also noticed that the A/C vent controls were inop; traced that down to a broke vacuum supply line and fixed it easily. After driving it around for a week or two I began to catch it up on its maintenence. I Replaced the plugs, cap, rotor, air filter, and had no problems for about a week and then it developed a rougher idle and a slight loss in power. A few days later, no start. I have another vehicle to drive, so I have been trying it occasinally and it will start periodically. When it does it seems to run well but only intermittantly. After it is started and warmmed up it seems to start like it normally does. After reading up on this site a few others I performed a fuel pressure test. It seems to have good initial pressure, 55-60psi and it drops slightly while running, and rises and falls according to the rmp. However, I have not checked to see if it looses pressure while it sits yet. I will do that next.... Anybody got any other thoughts on the problem? I do know that this is the first year of the new style fuel pump/sender, and that this is the vortec engins with CSFI fuel injection system. Could this be a pump problem, injector, or a pressure regulator problem? Ignition system seems to be O.K. and no codes... Seems to be a little rich when starting and carb cleaner/starting fluid seems to have little effect if any. Thanks- Frustrated in Atl

[MT-2500]

Originally Posted by ckmn

Well, after doing some reading and researching on this site and a few others I believe I have a fuel problem, but I would love some other opinions... I live in Atlanta and I recently bought my second Astro w/ 104k on it out of Chicago. My first one was a 1988 model and I simply wore it out, and my new one is a 1997 model 2wd LT. I noticed that it took longer to start than my older van, maybe 1-2 seconds more of starter spin. I also noticed that the A/C vent controls were inop; traced that down to a broke vacuum supply line and fixed it easily. After driving it around for a week or two I began to catch it up on its maintenence. I Replaced the plugs, cap, rotor, air filter, and had no problems for about a week and then it developed a rougher idle and a slight loss in power. A few days later, no start. I have another vehicle to drive, so I have been trying it occasinally and it will start periodically. When it does it seems to run well but only intermittantly. After it is started and warmmed up it seems to start like it normally does. After reading up on this site a few others I performed a fuel pressure test. It seems to have good initial pressure, 55-60psi and it drops slightly while running, and rises and falls according to the rmp. However, I have not checked to see if it looses pressure while it sits yet. I will do that next.... Anybody got any other thoughts on the problem? I do know that this is the first year of the new style fuel pump/sender, and that this is the vortec engins with CSFI fuel injection system. Could this be a pump problem, injector, or a pressure regulator problem? Ignition system seems to be O.K. and no codes... Seems to be a little rich when starting and carb cleaner/starting fluid seems to have little effect if any. Thanks- Frustrated in Atl

Hard to start cold.
Check cold start fuel pressure.
Check engine running fuel pressure.
Check engine running on the road fuel pressure.
Then shut it off and watch for fast leak down.
Pinch off at rubber part or block off return line and check full pressure.
Later V6 and V8 gm engines should have 60-66 fuel pressure.
Cold start should be 64-65 lbs of pressure.
If you do not have full fuel pressure on a cold start the injectors will not squirt fuel.
Do not leave home without it.
Engine running should be 60-66 lbs pressure depending on engine load.
Full pressure with return pinched off should be 75-85 or more.
And if it has a fast leak down after shut off you have a leak.
Post back fuel pressure readings.
MT

[drew300]

My '97 developed hard starting, but ran great.
Then it got to needing a 1 second spray of starting fluid, and still ran great.
I borrowed a fuel pressure guage, and had 59 lbs. I phoned GM Service, and they told me "minimum 60 psi". I said I had 59 psi, they said "minimum 60 psi"
So I changed out the pump, and have lived happily ever after. I returned the guage so i don't know what the present pressure is.

[MT-2500]

Originally Posted by drew300

My '97 developed hard starting, but ran great.
Then it got to needing a 1 second spray of starting fluid, and still ran great.
I borrowed a fuel pressure guage, and had 59 lbs. I phoned GM Service, and they told me "minimum 60 psi". I said I had 59 psi, they said "minimum 60 psi"
So I changed out the pump, and have lived happily ever after. I returned the guage so i don't know what the present pressure is.

10-4 on that Drew300
Even 1 lb low on pressure will cause a no start. I found that out the hard way to. Also very important to have a good accurate gauge when testing.
MT

[ckmn]

Hey thanks for all the info. I did find low fuel pressure...
40psi @ start up and 55psi running... no good... after replacing the fuel pump and repairing the pinched wiring harness we are back at 65psi at startup. By the way $300 for the fuel pump... ouch... Thanks for all the info Guys!

[MT-2500]

Thanks for posting back and letting us all know how it went.
Glad you got it going good. And yes 300$ is a big ouch but the 300$ one should be a good one.
MT

[drew300]

I phoned GM, they wanted $860.00 for the pump assembly, in a box.
I ended up with a Carter assembly, $460.00, with a few others at around $560.00. (Canadian)
Some-one wrote in that he used a pump form a Cavalier 4 clyinder.(something like $60.00) I looked at the assembly, and figured IF I got it apart, I'd need the asembly anyway, because I doubted I'd get it back together......