OK, guys I have a 1999 blazer and for about a month now I been having a problem at start up. It usually starts up as soon as the key is turned now itdoes not start until the second time I turn the key. Got a code reader and it came up misfire. But if i just turn the key on and not try to start it right away it will start right up so I am thinking it is the fuel pump. I have not pressure tested it yet because that is the only problem I have it runs just fine. Could this problem also be the regulator. I figured if it was the pump it should have went out by now. Thanks in advance for any help.

 

YOu current starting up is my normal one. Are you in winter now? Cold will do that... i always hold the key on to let the fuel pump prime. Doing a fuel pressure test is easy and quick and never a bad idea on these trucks. We can't answer your questions until you do one either.

 

I am in florida so it is really not that cold here. I plan on getting a pressure tester tomorrow. I did go out there and let the pump prime up then pushed the valve in on where the tester would go and fuel can out. Then did it again after I let it set for five minutes and nothing happened, no fuel.

 

Once you have the pressure tester, follow through the diagnostic in THIS POST.

My initial thought would be a failed FPR.

 

Ok guys been down for a while had to have surgery just got my pressure tester just wondering about what the pressure should be whenrunning and not running. And new symptom started today was running fine stopped at a red light and started to run rough and now has no power and also a weird smell is now coming from the exhaust but no smoke at all. Will test it tomorrow and have some numbers. Also think I am going to check the gas because about 30 minutes before this started I just filled the tank.

 

Checked the fuel pressure I have 55 with the engine on and 60 just for a sec with the engine off then pressure slowly drops. I thoughit just might be the regulator. I drove it up to autozone and they pulled the codes P0171;fuel to lean, and P0300random misfire. I changed the plugs and it still runs really bad and will change the wires tomorrow they had to order them for me. The guy at the store said it has to be the coil or distributor cap that is making the codes come up. Sense I just filled up the tank I though it might be bad gas but he told me that it will not bring those codes up even if it was bad gas. Any suggestions. At this point I am lost

 

Read this:
http://www.obd-codes.com/p0171
Did you read through the link that Kyle posted?
I would go ahead and change the distributor cap and rotor when I replaced the wires. Let us know.

 

Yes I read his post and I have also read over theLONG P0300 post. I have not checked the regulator yet but the pressure drops down to about 10 within 3 minutesafter the pump stops pumping. Ihave checked the lines for leaks but did not find anything. But the pressure from the pump while the engine is runningstays around 54-56 so I figured that the pump is working and that it just might be the regulator but I alsoknow that thepump itself could be leaking back into the tank. Far as the cap and rotor I looked them over and they looked find but I guess I can change them also and see if themissing will go away. I juststarted it up again and nowno engine check light is on butit is still missing just not as bad. Will also check the air flow sensor and will post back. Just to be sure that is the sensor towards the middle of the air box right or I am confusing it with the intake air temperature sensor.

 

The MAF is the sensor at the first connection in the air duct after the filter, between it and the plenum.

 

Thanks Guys for the help. I will trythese things tomorrow andhopefully post back with some good news.