The engine acts as if it is being starved of fuel. I can only keep it running by pumping or flooring the gas pedal. It will not idle at all. Its not throwing any Service Engine Soon lights, so I have no easy way to identify the problem. The fuel pump is almost brand new. It's been installed for about 3 months now, so I'm fairly sure that isn't the problem. Any ideas where I should start? Heres a video, it was filmed with my Galaxy Tab 10.1 so it makes the engine sound like a tin can , but maybe you can get something out of it.

http://www.youtube.com/watch?v=4k83G...n2gl3EgoYtE9k=

 

I would start checking fuel pressure, spark wires and spark.

 

Spark plugs and wires are literally brand new AC Delco's. I'll check the fuel pressure as soon as I can.

 

Idle air control valve? Im sure someone knows the values all the sensors should be putting out so you could check em.

 

The idle air control valve....... maybe. Thanks, ill check into it.

 

Throttle position sensor.. next to the IAC.

 

How did the problem occur ? where you just driving and it happened or went out to start it and it happened? Replaced something and the problem occurred?

 

Its strange, the car hadn't been started in a few weeks, and I had a new windshield wiper motor to install. So I started the car, pulled it into my garage (It was running perfect), and installed the windshield wiper motor. After that I took it out, washed it, and put some gas in the tank. (The car was still running fine) After that I put it back in the garage I store it in.The next week, I had some random interior parts to install so I went to pull it out of the garage, and about the time I'm about 100ft out of the garage the car sputters a couple of times and dies. I restarted the car, and all it would do is choke and die as shown in my video. So I do my best to keep the car running long enough to back in its garage. (Finally got it after about 5 minutes of starting the car slamming it in reverse and rolling about 10 ft each time.) I know what you're thinking,"Its probably just some bad gas". That's what I suspected at first, so I went out and bought gas treatment for the car, and let it sit for a week. Still runs terribly.

 

Can think of 3 things to check, one .. any sitting car's exhaust is perfect for something to crawl into it, could be a clogged cat/exhaust
If you got someone around, have them get on it while you hold your hand over the exhaust should have a healthy flow, if its weak, that's your problem!

I would check the plug wires for issues, maybe one is arc'in off somewhere! And seated very well!

Could be the cap on the rotor, check the guts on the inside of the cap and make sure they look good. Ignition control module could be on its way out, but normally it just stops working.

 

I finally got around to changing the fuel filter and checking the fuel pressure today. Strange thing is, when I took the filter off, fuel continuously poured from the lines. I thought the fuel pump was supposed to stop the gas that wasn't already in the line from leaking out. Please correct me if I'm wrong.
I couldn't check the fuel pressure down by the fuel filter because the lines wouldn't move enough for me to fit the connector on, So I followed the line up to the engine and connected the gauge there (Picture attached). When the fuel pump primed itself it only read 2psi, and when the car was running there was no fuel pressure at all. So I think either where I have my gauge attached isn't working, or there is a leak somewhere in my fuel lines letting air in.
I don't know. What do you guys think?

 

That's correct spot to measure FP on 3rd gen. Make sure that you are measuring the supply side (not the return). Supply lines are are larger diameter. When car is running you should see between 9 and 13 PSI per FSM.

//RF

 

Following this thread, I just started having the same problem with my RS today.

 

Fuel lines need to be lifted really high up to stop them from pouring fuel.
Adapter appears to be on the correct line, in the pic.
Make sure no air is in the gauge line, mine has a purge button for that purpose.
If still lower then RFmaster's posted values, you probably have, fuel pump power supply or fuel pump, failure.

 

make sure you are inline with the bigger line (3/8) and not the smaller one.

 

Hi,

I had a temporary issue like that for no reason. My car sounded like yours on the video. I did not have to step on the gas to keep it running but sounded awful. I thought it was running on 4 cylinders. So I checked the TBI and saw fuel coming out of only one injector. I disconnected and reconnected the one that had no fuel and it started spaying fuel again. I do not recall if I shut off the engine when I did that. If I did not, I should have since there could have been a spark when reconnecting.

Thanks,

JAlvarado

 

Not trying to hijack this thread, but I'm having the same problem the OP is having, I checked the fuel pressure, it read a little above 10 psi, so I think the fuel pump is ok. I started checking for vacuum leaks and such. I found that if I remove the PCV valve, that I can start the car, and it will run, I replaced the pcv valve with a new one and it still will not run with the pcv valve connected, any ideas? 5.0 TBI Automatic for info purposes.

 

Means nothing if:
1. The fuel tank has contamination--sediment, rust, grit, etc.
2. The wiring to the pump wasn't verified good. Defective wiring in the tank (on the sending unit) is an epidemic problem. Most fuel pumps come with a wiring upgrade. Was the wiring repaired/replaced?
3. The BEST way to verify wiring issues aren't a problem is to use an oscilloscope connected to the fuel pump wiring via a "low amps" probe; along with a voltmeter as close to the sending unit as practical. You'd better have very close to battery voltage at the fuel pump power wire by the sending unit; and the pump will be spinning ~6000 RPM and drawing about 6--6.5 amps when the engine is idling.

1. PCV valve is defective, allows too much air into the intake manifold.
2. (more likely) Engine is running extremely lean for whatever reason, eliminating some air by blocking the PCV richens the mixture just enough to allow it to run.

 

Thanks for the reply, I replaced the pcv valve, same situation. It's almost like there's an air blockage somewhere else and when the pcv valve is disconnected, it can get enough air to run then.

 

So you're not plugging the PCV, you're creating a big vacuum leak? I misunderstood what you were doing.

Start looking at your IAC. Perhaps the passage is plugged, or the IAC valve is seated and not allowing air flow.

This would be like starting the engine with the idle speed screw backed all the way out--the idle speed isn't high enough to keep the engine running.

 

Thanks, I'll take a look at the IAC.

 

I finally made a day out of it to replace the fuel pump, and sure enough that was the problem. The car runs like a dream now! Thanks for the advice everyone!

 

My problem turned out to be the IAC, just in case someone runs into a similar situation, thanks Schurkey and everyone as well.