2001 Astro difficult starting when warm, OK on cold start??

[dhspring]

Anyone experienced a difficult start on their Astro when the engine is warm? I have 102,000 miles and it runs great otherwise. It starts right up on cold start but when warm you have to hold the starter on for a few seconds to get her running. This is exactly like my other cars/truck when I had a bad fuel pressure regulator, when I changed that, problem was solved, only those have port fuel injection unlike the Astro. My Astro doesn't have an external fuel pressure regulator since it has throttle body injection, unlike the others that have port injection and pressure regulator on the fuel rail.

I'm thinking it's a fuel issue, I have checked the fuel pump pressure and it's good at about 50 lbs., have put new plugs, wires, dist cap and rotor on in the last year so I'm thinking it's something on the throttle body injection system. Any help is greatly appreciated so I don't have to visit the local Chevy Stealership.

[CD Smalley]

50 PSI is not good enough. It needs to be closer 60 PSI I believe.

[dhspring]

Yeah, 50 is probably not the right number, I'm sure I checked with the Chilton book when I tested it to make sure I had the correct number, I'm pretty sure the fuel pump is okay.

Can someone tell me how to do the fuel leakoff test? And what are the poppets some other post referred to as being a probable cause?

[brcidd]

see if this helps-- this van was "hard to start" as well -- because it was always flooded

http://www.automotiveforums.com/vbul...ght=documented

[Leeann94astro]

Originally Posted by dhspring

And what are the poppets some other post referred to as being a probable cause?

You don't have throttle body injection; you have sequential port fuel injection that's located under the intake manifold. It has poppet valves (one for each cylinder) and a fuel pressure regulator as a unit (kinda looks like a spider, hence the name).

I don't know what the fuel pressure is supposed to be on an '01, but it's something like 62 psi...but don't quote me on that.

[CD Smalley]

Again, 50 PSI is NOT ENOUGH. Search here. OldMaster has posted the exact figure. I think it does have to be 62 as Leeann stated above. That figure does ring a bell.

[dhspring]

Correct, I checked the Haynes book, the required fuel pressure is 55 to 64 psi depending on CSFI or CMFI but that checked out okay, otherwise it would not start cold either, I will recheck to be sure, but I'm thinking it's the fuel pressure regulator causing the problem, just checked with the dealer, it's $100, man, expensive critter.

[brcidd]

I'd make sure you don't have a leak, and that your fuel pump is capable of 62 psi before changing out a regulator- you can pinch off the return line to prove out fuel pump- a leak would show up in leak down test with fuel pressure gage attached- as in the video link I sent you.

[dhspring]

Thanks brcidd, will do. How difficult is it to change the fuel press regulator? It looks pretty simple from the Haynes book, is it plug and play, i.e. there are no settings or adjustments correct, you just bolt it in and go?

[homedesigns]

We focusing to much on fuel, how about our temperture sensors, have you got access to a scanner. I would check my ECT and IAT they are always suppose to be about the same temp give or take 10 degrees

[dhspring]

Thanks for the tip homedesign, I will check it out. It is not my fuel pump, I have 59-60 psi there, still might be the press. regulator but you have to take off the intake manifold to get to it, which I'm not going to do, right away. Hopefully it is something simpler as you have suggested.