91 Astro Hard Starting

I've got a 1991 Astro Van that has trouble starting after it sits for a while. The engine cranks it fires, runs for a few seconds then dies. This can be done for 10-15 minutes and then it will start and stay running and run just fine until I let it sit for anywhere from 3+ hours on then the hard starting comes back again.

Just to let you know, this van has over 200K miles and did sit idle for a long time (1 year) before I acquired it and started driving it. The people that owned it before me are friends and the guy is a mechanic and very meticulous in his vehicle maintenance.

I've done many repairs to this van in the last year that I have had this vehicle. I replaced the fuel filter and fuel pump last August '03. In January of this year I had a major tune up and oil change done, with new plugs, wires, cap, rotor, timing, service check, you name it the works and it ran fine until about 2 months ago and the starting problem began.

Most recently (just this last weekend) I replaced the ECM box to see if that was the problem. I had an 87 Cavalier that did the same thing this van is doing and replacing the ECM cured the issue. As for the van, it still has the same issue.

I've read alot of the posts on the site here and hear tell of fuel pressure, problematic fuel pumps, bad alternators, vacuum leaks, catalytic converters, etc...... I guess I am looking for ideas where to look next. The van does need exhaust, should I look into the converter or test the fuel pump pressure? The van runs and drives perfect when it start, does not stall or rough idle.

I would appreciate any thoughts and ideas on this.

Thanks alot for any help.
Brian

Given what you've replaced, Heat soak and a failure to start would have me looking at the fuel pressure regulator next. Get a FP tester and see what level FP you are getting when the hard starting happens.

TBI should have FP of 9-13 psi
CPI should have 55+psi I think not sure on this one.

Given what you've replaced, Heat soak and a failure to start would have me looking at the fuel pressure regulator next. Get a FP tester and see what level FP you are getting when the hard starting happens.

TBI should have FP of 9-13 psi
CPI should have 55+psi I think not sure on this one.


Thanks for the information, I am going to check that out and also check out the cost to replace the exhaust as it needs it anyway. These are good, strong, sturdy vehicles and it's worth putting a little money into them.

Thanks again,
Brian

Hi Brian: I have an 86 Astro with 230,000 on it. About 6 weeks ago, it started acting up; wouldn't start except with a lot of cranking. After three or four times of hard, long cranking, it would start. Roughly at first and then it would smooth out and run fine; still got great gas mileage. After it sat 5 or more hours, same thing again. It was in the shop more than in my garage. Changed all kinds of things, including the distributor and the computer. Didn't help and about broke me. Finally I was desperate and called an old-time mechanic who told me to run the tank to under 1/4, put in a quart of LACQUER THINNER, run it almost dry and then fill it up again. Know what? It's almost back to perfect starting. What he told me was that since there isn't lead in gas any more, gunk accumulates in the tank, especially on vehicles with as many miles as ours. The lacquer thinner vaporizes that gunk and it goes out as our use the gas. It won't hurt the fuel injectors, fuel pump or anything else, either. I'm going to do it once more to make sure I have all the gunk out. He also said to do it every fall and spring; you can bet I will. Hope this helps. Just make sure you use lacquer thinner--not paint thinner.