Stalled Omni

[SL#189]

Just fueled up, within 10 miles the Omni felt like it was dying (then restarting since I was in gear at 60MPH). When I pulled off the freeway, the idle surges, almost dies, surges. City driving it also tries to die (bucking, running good for a sec, bucking, etc.). Pulled into a parking lot and got codes 33, 47. After disconnecting the battery, the car will barely start (sometimes) and dies if I don't keep a little pressure on the gas pedal - too much pedal and it will sound like it's going to die again (sometimes it will pick up and run good for about 30 sec, then go back to surging) - Power Loss light is on the whole time now (wasn't on before disconnecting the Batt.). This is my daily driver - I need ideas ASAP - help!

Thanks in advance!

[88_pacifica]

33 and 47? That's odd... Is your AC on? Sounds like really bad gas to me.

[Turbodave]

I would get check your battery voltage, both while the car is off, and when the car is running. The code 47 has to do with the charging voltage too low.

When the alternator went in my shadow it acted like you describe, I was able to drive the car around a little but it acted crazy with the voltage jumping around.

[SL#189]

I thought those were odd codes as well - the AC/heat is off... The interesting thing is that it sounds like it's not getting enough or a constant supply of fuel. I suspect a weak pump (I can hear it run - same noise it's had since I bought the car). After Batt. disconnect, I get the usual code 12 and also a code 13. It definitely seems to be in limp-in mode (wont rev past 2000 RPM now).

Voltage check is on my list for when I get back to the car with tools.

[88_pacifica]

check the fuel pressure too... if possible

[Keito]

check the fuel pressure too... if possible

X2
Sounds like the fuel line burst in the tank or fell off.
I have experience.

[clarkwhoracing]

Just fueled up, within 10 miles the Omni felt like it was dying (then restarting since I was in gear at 60MPH). When I pulled off the freeway, the idle surges, almost dies, surges. City driving it also tries to die (bucking, running good for a sec, bucking, etc.). Pulled into a parking lot and got codes 33, 47. After disconnecting the battery, the car will barely start (sometimes) and dies if I don't keep a little pressure on the gas pedal - too much pedal and it will sound like it's going to die again (sometimes it will pick up and run good for about 30 sec, then go back to surging) - Power Loss light is on the whole time now (wasn't on before disconnecting the Batt.). This is my daily driver - I need ideas ASAP - help!

Thanks in advance!

I agree with Keito on that one. I had my omni I just bought in PA die on me at 2:30am in PA coming home and the next day the shop went top to bottom and then checked the fuel pressure and it was almost not there so we pulled the fuel pump and the rubber hose had a big --- hole in it.

The car would run but under load took a crap somewhat like yours.

I would pull check the fuel pressure if you could and from there do the fuel pump looky.

[SL#189]

Ok, I didn't think I could check fuel pressure without the car running, so I've pulled the pump. The sock is brown-black (should be whitish?), the internal hose "looks" ok, although I may replace the pinch clamps. I had a thought though when using the pump to drain the gas - can you check fuel pressure by jumping the pump (installed of course) at the coil? Would that help me diagnose a possibly bad regulator?

You guys rock!

[88_pacifica]

Replace the hose, but make sure it's not the junk from Autostoned or Advance Auto, etc.... make sure it is high-pressure, high quality line. Ask Simon first, because there's a "technical name" for that stuff and I'm sure he remembers what it is.

I would be willing to bet that's why you were having issues. You "technically" can hotwire the pump, but make sure it's totally immersed in the tank to prevent it from burning up and killing itself. "Keying forward" in the accessories postion also activates the pump too...

[tryingbe]

SAE 30R10 line.

You want fuel line that is RATED intank. Or else the fuel line WILL melt, it's just a matter of time.

[Dodgeglht]

You say you have code 13? That's Map sensor vacuum. Check the vac lines to the sensor & manifold. Sounds like an issue there. I know my car acted like that when the vac line to the sensor was disconnected.

Matt

[SL#189]

You say you have code 13? That's Map sensor vacuum. Check the vac lines to the sensor & manifold. Sounds like an issue there. I know my car acted like that when the vac line to the sensor was disconnected.

Matt

That sounds like my next issue to look into - I assumed the code 13 was because the car stalled. I opted for fuel system rebuild, short of the steel lines (new pump, new F.I. grade rubber lines front & rear, new regulator). The issue still exists. WHEN it starts, it will only stay running at 1/4 throttle or less (but not with no throttle). No throttle it will die. More than 1/4 throttle, it surges until I back off the throttle to 1/4. The Power Loss light is on all the time. Current codes are: 12, 13, 52, 55. (Batt, MAP, O2 sensor, end).

Despite the codes, is it possible TPS or HEP failure? (don't worry, I'll be checking the other stuff first).

[Turbodave]

That sounds like my next issue to look into - I assumed the code 13 was because the car stalled. I opted for fuel system rebuild, short of the steel lines (new pump, new F.I. grade rubber lines front & rear, new regulator). The issue still exists. WHEN it starts, it will only stay running at 1/4 throttle or less (but not with no throttle). No throttle it will die. More than 1/4 throttle, it surges until I back off the throttle to 1/4. The Power Loss light is on all the time. Current codes are: 12, 13, 52, 55. (Batt, MAP, O2 sensor, end).

Despite the codes, is it possible TPS or HEP failure? (don't worry, I'll be checking the other stuff first).

A good indicator of a dead or disconnected MAP is that the car will only run right at 0" vacuum. Look at your boost/vac gauge when it's running and I would guess that 1/4' throttle puts it right at that o" point. The code 13" indicates that the map passes the electrical test for an open of short (code 14) and is not seeing a pneumatic signal. So first make sure that there is actually vacuum and boost making it to the sensor, if that's good then try swapping the sensor out.

Another thing to look for since it's an Omni and throwing lots of codes is that there isn't any corrosion on the logic module connectors. L-body's are notorious for leaking under the cowl and dripping water right down onto the logic module. I've seen many with furry green connectors on the LM, despite the factory bag being in place.

[t3rse]

like mentioned, if you are going to hot wire the pump, be careful, they will die very very quickly if run dry, i killed one emptying out my tank using the pump, but the check valve was kaput so i was replacing the pump anyways.

[Gaboon]

I would check your map (vac hose)

Try another map if the vac line is good.

[SL#189]

Checked vacuum at the solenoid, then where it connects to the MAP - vacuum is definitely present (15-20 on the guage). Connector pins on the LM are amazingly clean and shiny despite small rust patch on the back plate of the LM box (outside only). I checked all the solder joints just because. Checked connector sockets using a light behind the connector - all look great - same with the MAP connector. Code 13 persists. Looking more and more like MAP issues - at least it kicked me in the butt to freshen the fuel system

[SL#189]

RESOLUTION: New MAP sensor

Thanks everyone

[dodge80_89]

I was going to say sounds like the map sensor. I had an 88 lebaron TBI and it did exactly the same thing you described. Disconnected the wires and it ran perfectly. Congrats on getting it going.