Truck wont stay running

DADDYDEC21

MEMBER
1993 CHEVROLET S-10
V8
2WD
MANUAL
212,456 MILES

Ok I bought a 93 s10. Put a 350 in it from a 1990k5 the truck ran fine no problems. Then all of a sudden it did not want to go past 3000 rpms. When it hit 3000 you can look under the hood and see the fuel spray isent a perfect cone anymore. I got 12psi at the tbi I replaced fuel pump, filter, timeing chain and gears, distributor, injectors regulator all them parts were changed new along with new plugs wires cap and rotor? Im stumped it will idle perfect but when undrer load are 3000 rpms one its fact it goes I need help thanks in advance

Wednesday, April 27th, 2011 AT 4:17 AM

3 Replies

RASMATAZ

MECHANIC
75,992 POSTS

Could be caused by one of the following below

Oxygen sensor.
Catalytic converter.
Fuel injectors dirty/sticking.
Mass airflow sensor/Airflow meter.
Throttle position sensor.
Crankshaft position sensor
Knock sensor
Manifold absolute pressure sensor.
EGR Valve
Fuel pressure regulator leaking or defective fuel pump.
Fuel contamination.
Foul/defective spark plugs.
Open spark plug wires.
Ignition coil/Coil packs defective.
Incorrect ignition timing.
Cap and rotor.

Note:If it doesn't apply disregard it and keep testing.

Was this

answer

helpful?

Yes

No

Wednesday, April 27th, 2011 AT 10:42 AM

DADDYDEC21

MEMBER
2 POSTS

02 sensor not hooked up, fuel injectors are new, no cats, tps mesures 5volts .456 at idle 4.109 at wot, masaif there is none on this truck, crank shaft and knock sensor crank shaft sensor is in the distributor which is new, no maps, nw regulator and pump, new gas and clean tank, new plugs and wires, coil was tested and is good, timiing is at 0deg tdc, cap and rototr is new?

Was this

answer

helpful?

Yes

No

Wednesday, April 27th, 2011 AT 1:03 PM

RIVERMIKERAT

MECHANIC
6,110 POSTS

Try flushing the fuel lines. It sounds fuel starved. Has the computer been put through its "relearn process"? What are you using for input voltages for the sensors you've removed or bypassed? Are there any codes stored by the computer? You should have more than 12PSI at the TBI, what do you have at the regulator?

Was this

answer

helpful?

Yes

No

Tuesday, June 14th, 2011 AT 5:19 AM