PLEASE HELP!!!!!

KORNBREAD · February 22, 2009, 06:07:42 PM

ok 1987 chevy k5. tbi 305. bought blazer last week. it would sputter and have a hard time taking off when it was first started and drove. brought it home threw in new plugs,wires,already has new cap and rotor. then took it down the street and filled it up with fresh gas. she stared to drive alot better. still had a hesitation when i would go to take off but not like it did. so i drove it for the last 3 days and the more it drove the better it ran.(the blazer sat for year and half before i bought it). well yesterday i took it to the junkyard to buy parts then drove straight home. i parked it then went in the house. came back out an hour later and it wouldnt start! it would turn over but didnt try to fire. its getting great gas flow threw the tbi,great spark, no vacume leaks. so i put a new egr valve in it and she fired right up. ran for about 5 mins and flooded its self back out and stalled. now heres the kicker. if i unplug the 2 injector clips from the tbi and crank it over it will fire up and run strong till the gas in the motor burns off. then when i plug the injector clips back in it will fire right up run great then it will start flooding out after 1 min of runing. BUT!! if i restart it and unplug just one of the injector clips it will stay running but will rev high. im totaly stuck. please help me. why dose it keep flooding its self out? would a bad map sensor cause this? please help me. this is my dd.

also sence ive bought this blazer when i would go out in the morning to start it for work it would rev higher than normal till it warmed up. dont know if this is part of the prob but i want you all to know the whole story and the problems it has.

mudslayer2008 · February 22, 2009, 06:47:36 PM

hard to pinpoint without trouble codes but it could be map sensor, tps (throtle postion sensor) or it could even be crank or camshaft sensor or fuel pump relay.
All of which are routed to the pcm and can control fuel pressure, when the fuel pump is activated and so on and so forth. But those are the most common problem areas I would probolly start with the relay and go from there its basicly going to be source of alimination. Just tring to help ya out to the best of my knowlege with what you discribed

Mudbuster · February 22, 2009, 08:35:00 PM

Find someone with a fuel pressure guage and check the fuel pressure it should be around 14 psi. My guess would be the pressure regulator is stuck (it's part of the TB).

KORNBREAD · February 22, 2009, 10:49:11 PM

whats the pressure regulator look like and where is it at so i can take a look at it? i know its getting to much gas cause it runs fine but it will just flood its self out after about 2 min of running and the spark plugs are fouling out like a bytch!!

Chevy Racer · February 22, 2009, 11:02:44 PM

could the O2 sensor be bad too. I know my old TBI S-10 ran really rich and the check engine light would come on when it warmed up cuz the O2 sensor was MIA.

KORNBREAD · February 23, 2009, 03:12:28 AM

ok wheres the pressure regulator at?

Disturban · February 23, 2009, 03:25:50 AM

Quote from: KORNBREAD on February 23, 2009, 03:12:28 AM
ok wheres the pressure regulator at?

It's right on the TBI and looks like this

Disturban · February 23, 2009, 03:29:15 AM

This may or may not be your problem but more than one time they have caused funky symptoms like yours. There is a spring in there and it might be weak so once your motor warms up so does the spring causing it to expand and run better. I would also check for a leaking intake and tbi gasket.