Acceleration woes

[Steve_O!]

Hi gang. I purchased a 2003 Le Mans about a year ago now. I got it for a song because she was running so poorly. After finding this website I started doing different things that I read about through these forums. Tested the TPS (is good), replaced the cross over exhaust pipes with ones I got from Scud with the cross over pipe removed and openings welded up (made HUGE improvement!), installed new plugs. Good news is that she's now very ridable but I have to be very gentle opening up the throttle or she falls flat. If I'm doing 40 MPH and just gas it it looses power until I get back off the throttle. Any ideas what to look at next. (Obviously I'm no mechanic!)

[Scud]

My first guess is fuel starvation. Maybe replace the fuel filter as a quick and cheap first step. Then look at the condition of fuel lines and pump. My Greenie had similar, but more severe, symptoms (also got her in exchange for a song). It turned out that the inlet to the fuel pump was partially blocked by decayed bits of the fuel line. The Greenie is external pump, and your 2003 LeMans has internal - so the pieces are different, but the principle should be the same.

[docc]

Starting points:

 

1) High Current relay(s), especially Position#5 (fuel injection/ ignition).

 

2) Complete Decent Tune-up including baselining both the TPS and the CO Fuel Trim.

[bbolesaz]

Bad TPS sensor ?

 

Steve-O are you aware of the Phoenix MGNOC breakfast meeting, this Sunday 8:00AM at Denny's I-17 & Bell. 

[Steve_O!]

Thanks guys. Let the search begin! I'll try to make the Sunday morning meeting. Thanks for the heads up bbolesaz!

[docc]

Starting points:

 

1) High Current relay(s), especially Position#5 (fuel injection/ ignition).

 

2) Complete Decent Tune-up including baselining both the TPS and the CO Fuel Trim.

Links added . . .

 

I've seen more than a few running issues evaporate with the High Current Relay(s), especially in Position #5 . . .

 

Also, be certain your battery is up to full State of Charge and the terminals are clean, tight, and sealed with a secure main ground path.

[Kiwi_Roy]

I'm with Scud but it might also be a weak spark, first of all with your multimeter measure Ohms from each plug cap to chassis, the reading should be the same on both sides, report back.

 

Make sure you don't touch the meter probe tip it might confuse your body reading with the coil spark lead reading