5.7L stumble on start with gas smell

[winsett]

Hi all....Below is a thread I posted in the 'blazer' forums, but one of the guys in there told me I might have better luck getting help with my 5.7L FULL SIZE BLAZER (1994) :


STUTTER START - SMELL GAS

Heres the truck:

1994 Full-Size Blazer 4x4
5.7L 350 TBI
Automatic Trans

Symptoms:

Upon starting truck (easy), engine trembles/shudders for a few seconds before settling into a steady rhythm. I notice a strong smell of raw fuel immediately which disappears after a few moments.
I will however, smell fuel again if I rev up the engine a few times while parked.


One should be aware that this is not the first time that I've encountered fuel delivery problems.
Almost one year ago, I replaced my fuel pump, fuel sending unit, fuel filter, O2 sensor, plugs, rotor, and alternator.
The fuel pump and sending unit were replaced due to a complete lack of starting.
The rest of the replacements came because I experienced a hesitation when accellerating quickly. Sometimes the truck would even lurch forward and almost stall during one of these hesitations.

Thanks to the tips from this forum, this hesitation problem was solved by a tightening of the distributor cap (seems I must have not tightened it after replacing the rotor) as well as resetting the timing with a timing gun. Things were running fine after all this until now.

The fuel problem now seems only to be present at start-up, although sometimes when i let Pedal meet Metal, i again notice a slight hesitation before the truck drops into passing gear.

I'm hoping there is a reletively easy solution to this new problem and I trust that someone out there reading this knows what i am dealing with.
After reading some of the replies from Blazee and BlazerLT, I look forward to hearing their thoughts on this one.

Thanks for your time

[SpitAndDirt]

How many miles are on it? Have you thought about your ignition module causing you problems with rough starts?

[Dr. Eagle]

Originally Posted by SpitAndDirt

How many miles are on it? Have you thought about your ignition module causing you problems with rough starts?

The other thing I'd look into is the injectors in the TBI. I had a similar problem with my 350 in my 92 suburban. One of the injectors would stick open...

[010175]

I have a 1999 with a 5.7 engine in it and 150,000 miles. It starts right up on the first start of the day. Last week it got real hard to start when the engine was hot. You have to turn the engine over a long time before it cachets. When it dose cachet the RPM are about 400 and then slowly moves to 600. I replaced the plugs but that did not help. I noted that the tail pipe had a LOT of black soot in it. Does this sound like your problem. I replaced the fuel presser regulator and fixed it. dave