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1.5 liter engine.--No Throttle

I have a `93 Eagle Summit.It will start and idle just fine. However when you step on the accelerator the engine attempts to die -smother out. Upon releasing the accelerator it goes right back to a perfect idle. I assumed the fuel filter was clogged,changed it out. I next dropped the fuel tank ran fuel pump to a gauge,+50 p.s.i. I put tank back up and tried closing off regulator return line

-gradually. Still no change. Next I removed air filter. No help. I recently changed out plugs, wires, and rotor. I have also ohm-ed the TPS sensor and it seems fine. Last item on diag. info is I don`t have a check engine light on while running. Any comments,ideas, or info greatly appreciated.

Reply to
tbonehead
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Does it still falter if you gently open the throttle? Make sure there are no vacuum leaks on the small hoses, and the big hose to the brake booster.

It sounds like fuel starvation. This can only happen if

a) the fuel filter is clogged, but you say that's been changed.

b) the fuel hose from the filter to the fuel rail is blocked or damaged internally. Take it off an blow air through it both directions, then see if a piece of welding wire or similar will pass all the way through. The fuel rail should have residual pressure for a while when the IGN of off.

c) the injectors are either clogged with gas gum or they are not getting fired adequately by the ECU. There should be +12V on the thick wire that connects to the injector. The thin wire is switched to grounded by the ECU. Pull the injectors out and have a look. If you don't have +12V (should be the same as alternator/battery voltage) on the injector, look at the MPI relay behind the radio, then the circuit that supplies +12V to the relay.

d) If the injectors are OK, look at the valve timing. A slipped belt will allow the engine to idle, but it won't rev.

e) have you swapped out the ECU?

Stewart DIBBS

Reply to
Stewart DIBBS

I had the same problem with the 1.5 liter, 94 mirage. i would start by unplugging the battery and reset the computer. There were two problems with my car, one was a small gear in the throttle body. I removed the TB then removed a small cover on the side to expose the gear. the small gear is black and part of the teeth were cracked. What i did was reposition the gear, i believe it ossilates back and forth so i guess (only guessing) i set it so the teeth engaged all the way. that also seemed to help.

something i also noticed was a small hose (vacuum) off of a solenoid on the firewall. i put that back and this seemed to correct the bogging while accelerating. I would look into both of these things. I acutally had to drive the car while it was bogging, it was something esle trying to climb hills. I had to get a running start, the car would bearly accellerate in ea. gear.

Hope this helps. BTW, Stew is VERY knowlegable with these things..

Reply to
Branigan

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