Delayed Starting (already searched)

[BlazerLT]

That or you might need to replace your fuel pressure regulator.

Have you checked fuel pressure yet?

If not, do so before you do anything else.

[kmkommes]

I have a 2000 blazer with the exact same problem, when first starting, it cranks fast and strong but does not fire not 3 seconds or so. If I tunr the key on and let fuel pump prime then I try to start it it seems to help alot. I put a fuel pressure gauge on it and showed that when the key was off or basically whenever the engine was not running and the fuel pump was not running the pressure would be zero... there is a leak somewhere. The fuel pressure is suppose to hold at 60 lbs or so, the problem is when I turn the blazer over the fuel pressure isnt there to let the engine fire right away.

NEW fuel filter...

I have read and read and read and have found there are multiple probelms with this style fuel injection system. I narroewed it down to the fuel pump, fuel pressure regulator, or possibly a leaky injector or whole injection unit (spider thing).

it looked as though the fuel pressre was fine so I didnt think it was the fuel pump... I thought maybe there was a check valve that was leaking fuel backwards though the fuel pump... not sure about that. I went with the assumpitoin of a leaky fuel regulator.. I changed that last night $85 part at carquest. That did not fix the problem.

Fuel pressure still leaks to zero. I did notice when I had the plenum off that the passenger two front cylinders were all black and oily. The whole drivers side was clean and the rear pass side partly clean.

I am suspecting I need to buy the whole CMPI or SCPI unit or whatever it is called.

My blazer runs great other then the bad start and horrible gas mileage. It idles fine and has plenty of power. I will update when I find the fix someday.

[kmkommes]

I will add that mine too always starts on the second attempt. I believe this is because when you turn the key off the fuel pump runs again for 2 seconds, ( to make sure there is pressure next time you go to start) While it is pumping usually there is enough pressure to make it start.

[BlazerLT]

You need to prime the system first by first turning it to the on position so the pump can prime the fuel lines.

Then you can start.

It doesn't turn on when you turn the key off.

[kmkommes]

Fuel pressure is not suppose to drop when you shut the vehicle off. It should hold. If it drops you have a leak somewhere.

I understand that turning the key "primes" the fuel pump and it will start after that, but that does not fix my problem, and yes it is a problem. If I turn the key to prime my pump and wait 2 seconds it is at 60lbs or so. If I wait 3 seconds it has already leaked down to zero already because there is a leak in my system, (and others also,JoshBarber). You should not have to "prime" the system, that is not normal. You should be ableto jump in and turn the key forward and the engine "should" immediatly fire.

I know what a running fuel pump sounds like. My fuel pump runs for 2 seconds when I turn the key on. It also runs for 2 seconds after turning the key off. I am not sure why it runs for 2 seconds when I shut the truck Off. I was guessing it does that to make sure pressure is there so when you jump in your car the next day it will fire right up without having to "prime" the system.

I have a 2000 ZR2 S10 Blazer
My 1994 GMC SOnoma does not cycle the fuel pump when shutting the truck off.

[lostmartian63]

another thing you may want to do is put some fuel system cleaner in it. Its all pretty much the same so it will all work. Another thing you can do if your owners manual says you can put methnol in it is put a pint of everclear in with a full tank of gas my dad does this on his drag car when its time to clean the carbs. Incase you dont know everclear is 190 proof corn liquer witch is basically racing alcohol but make sure your engine is made to run a 10% mix of methnol before you do this or you'll really fuck it up bad. I know the 4.3 NON vortec engines can use it but im not sure about a vortec.

[BlazerLT]

Originally Posted by kmkommes

Fuel pressure is not suppose to drop when you shut the vehicle off. It should hold. If it drops you have a leak somewhere.

I understand that turning the key "primes" the fuel pump and it will start after that, but that does not fix my problem, and yes it is a problem. If I turn the key to prime my pump and wait 2 seconds it is at 60lbs or so. If I wait 3 seconds it has already leaked down to zero already because there is a leak in my system, (and others also,JoshBarber). You should not have to "prime" the system, that is not normal. You should be ableto jump in and turn the key forward and the engine "should" immediatly fire.

I know what a running fuel pump sounds like. My fuel pump runs for 2 seconds when I turn the key on. It also runs for 2 seconds after turning the key off. I am not sure why it runs for 2 seconds when I shut the truck Off. I was guessing it does that to make sure pressure is there so when you jump in your car the next day it will fire right up without having to "prime" the system.

I have a 2000 ZR2 S10 Blazer
My 1994 GMC SOnoma does not cycle the fuel pump when shutting the truck off.

Sounds like the fuel pressure regulator is shot.

That or the check valve on the sending unit is stuck open.

My money is on the FPR.

[kmkommes]

I already changed the fuel pressure regulator 2 days ago as stated in above post. It didn't seem to help. So now I am looking at a new spider assembly or possibly the fuel pump.

Is there a check valve in the fuel pump? Seems if there was that could easily be the problem. I wasn't sure if there was or not so haven't went that route yet.

I guess what I could do is have the system build pressure. Then block the line above the fuel pressure gauge to see if the leak is on the intake side or the gas tank side of the gauge. That would definately help narrow doen my search.

But then again, when I had my plenum off one whole side of the engine was much cleaner then the other, with what I have read that "should" mean there is a leak there. I just dont want to spend $300 and not fix it.

[chatalex71]

Hi im a newbiee her ebut i have expirience whith cars I have the sane issu but I was wonderimg if a bud altinator could sause it becuse my lights, turn signals are week And my engin is fairly new / just bought the car from saturn whith new engin

[BlazerLT]

Originally Posted by chatalex71

Hi im a newbiee her ebut i have expirience whith cars I have the sane issu but I was wonderimg if a bud altinator could sause it becuse my lights, turn signals are week And my engin is fairly new / just bought the car from saturn whith new engin

Whoa, slow down there and type normally please.

Yes, the alternator could be bad if your headlights are weak amongst the the other electrical things with your car.