[01mali]

Hey everyone have been dealing with this isssue for the last couple days. the car will turn over and run for about 5 seconds but it is very rough like its not gettine enough gas and then it shuts down. my wifes grandpa said the fuel pump wasnt workin and he changed that and it still wouldnt work so after some research i found maybe the cps was bad and he replaced that and the car worked fine for about ten minutes. and then it died on me on the side of the road and same thing will turn over and run for about 5 seconds and then shuts off so im thinkin i just wasted money on fuel pump which didnt need to be done. the anti theft light isnt blinking. anybody have any ideas what is going on i would appreciate any help Thanks.

 

[DrivenDaily]

Check the fuel pump relay to see if the contacts are pitted. (If you don't want to open the relay then borrow one from, say, the headlights, and see if it gets better.)

When I read this I thought right away that the start circuit is energizing the fuel pump to prime the system, but once started the system doesn't keep it energized. You may have a bad processor! But with the cost of those do other things first to make sure if it is or isn't a bad one.

Also, see about getting/borrowing a pressure gauge that can be used on gas. Check it immeditately after turning the key on. Then while it's running check it again. If it stays where it should (guessing here - ~50-70 PSI is commong on FI) then the pump is working and something else is the issue. If it drops then check the fuel pressure regulator.

You can get quite inventive in diagnosing this. The relay simply provides power to the pump. Pull it and then find the 12V supply and the contact going to the pump. Jump them (caution: do this at your own risk!) and see if that cures your problem.

Find the wire leading to the pump and put a test light on it. When the key is turned on it should light for anywhere from 1/2 a second to several seconds and then turn off. Once it's running it shoud turn on continuously.

When did you last change the fuel filter?

 

[01mali]

i was not home when her grandpa came to get the car but i believe the checked the relay and that the fuel filter was changed. what is a processor and how would i check to see if its working

 

[DrivenDaily]

Processor, aka PCM (powertrain control module) or ECM (engine control module). To see if it's functioning properly you might be able to use a scan tool that you can buy/rent/borrow, or you may have to go whole hog and take it to the dealer or a shop. Try all the other avenues first. Many problems that pop up so quickly tend to be simple. I hope yours is!

 

[Starship]

Did anything significant happened recently or has this problem been getting worse over time? Do you have any scanner readout?

DrivenDaily has covered the fuel supply issues. I don't know what to make of running 10 minutes after a new CPS sensor. I'm thinking (a shot in the dark) you may have a totally plugged-up catalytic converter. If it had shifted, excessive unburned fuel could've melted the innards.

 

[01mali]

before this happened i noticed that occasionally i would give it gas and it wouldn't just go it would feel kinda of jumpy it would just jerk a little bit but it has never done this no starting thing. and the cps sensor he put a new on in and he said was working so we went to go pick it up drove to her parents then on the way home it just died. so i am not sure i am kinda at a lost have been doin alot of searching but not sure. guess i will try and check the fuel pressure to see if the reg is working. once the car starts the rpms really get choked down till the car finally stops almost as if it isnt getting gas.

 

[ElantraMax]

Some of the 3.1s, I forget which ones, Had a wiring problem. One of the wires going to the Ignition module was broken. This was on the 3.1s with the Coil/Module mounted between the engine and radiator. On the side of the block.

 

[01mali]

it does have a 3.1 would the car even start with the ignition module broken

 

[ElantraMax]

Its a wire. Car engines are programmed by the factory to shutdown the fuel pump within 3 seconds or so. Incase of an accident. The computer doesnt receive a Tach signal, It shuts down the pump. Its actually a Federal DOT requirement. To prevent fires, spills.

 

[01mali]

oh so if the wire was broken then the car may start like it is but then it shuts down the fuel pump?

 

[Starship]

With all due respect, this sort of exchanges are counterproductive. Perhaps you could get her grandpa to come online and provide us with more details on what's been done and why?