my truck starts but runs rough like bad fuel pump

[wheele rider]

I was wondering if anyone else had this problem. When I first got the truck I put in another fuel pump because it wouldn't even start unless I used starting fluid. But the pump I installed was use and did the same thing . So I just put in a brand new aeromotive 340 and now it starts on but runs rough unfilled warm then it idle's fine but still seams like its not getting fuel. Anyone have any problems from the aeromotive 340? Could it be the oil pressure sending unit? Need help ASAP thank you ;-)

 

[5678TA]

Re: my truck starts but runs rough like bad fuel pump

Try a new o2 sensor.

 

[Beavis]

Re: my truck starts but runs rough like bad fuel pump

IAC might need cleaning

 

[wheele rider]

Re: my truck starts but runs rough like bad fuel pump

Also when I push the gas even when its warm it seem to be starving for fuel ?

 

[5678TA]

Re: my truck starts but runs rough like bad fuel pump

Fuel pressure regulator? i'd say most likely your fuel pump is good. Did you change fuel filter?

 

[BoostedSUV]

Re: my truck starts but runs rough like bad fuel pump

Do you have a fuel pressure gauge hooked up?

 

[wheele rider]

Re: my truck starts but runs rough like bad fuel pump

Yep changed the filter when I put in the new pump. And the fuel pressure was 38-40 I think.

 

[Shawnss]

Re: my truck starts but runs rough like bad fuel pump

Yep changed the filter when I put in the new pump. And the fuel pressure was 38-40 I think.

is this at idle or revving it up? its not real bad fuel pressure but for a aftermarket pump its not crazy strong. im just wondering.

 

[BoostedSUV]

Re: my truck starts but runs rough like bad fuel pump

is this at idle or revving it up? its not real bad fuel pressure but for a aftermarket pump its not crazy strong. im just wondering.

If that's running with the vac line connected that's probably about right. Won't matter what pump is there, the regulator controls the pressure

 

[wheele rider]

Re: my truck starts but runs rough like bad fuel pump

Yeah that's with the line connected.

 

[bonesdmz]

Re: my truck starts but runs rough like bad fuel pump

How old is your ICM?

 

[jaystcb]

Re: my truck starts but runs rough like bad fuel pump

Also when I push the gas even when its warm it seem to be starving for fuel ?

Now that it is running. Check the timing (0 @ TDC).

If that is good, check for a vacuume leak.

 

[jaystcb]

Re: my truck starts but runs rough like bad fuel pump

Also when I push the gas even when its warm it seem to be starving for fuel ?

Now that it is running. Check the timing (0 deg. BTDC).

If that is good, check for a vacuume leak.

 

[wheele rider]

Re: my truck starts but runs rough like bad fuel pump

The timing is @ 0. And the icm I take it u mean ignition control module? If so its original

 

[BoostedSUV]

Re: my truck starts but runs rough like bad fuel pump

The timing is @ 0. And the icm I take it u mean ignition control module? If so its original

Is that with the brown wire disconnected? If not than that's your problem

 

[wheele rider]

Re: my truck starts but runs rough like bad fuel pump

Yep brown wire on passenger side disconnected

 

[jpalmer]

Re: my truck starts but runs rough like bad fuel pump

I'd say vacuum leak on intake manifold.

 

[5678TA]

Re: my truck starts but runs rough like bad fuel pump

I really think you should try an o2 sensor. I had similar problems, wideband confirmed even... Running lean then it going even leaner as I tip in the throttle. Fuel pressure on mine was fine too.

 

[Beavis]

Re: my truck starts but runs rough like bad fuel pump

Idle Air Control and O2 sensor. :2cents:

 

[wheele rider]

Re: my truck starts but runs rough like bad fuel pump

So it seems that some fool changed the stock injectors and put in 3.4L camaro injectors in there place..... So now I need stock injectors but moneys kinda tight now so I'm gonna wait for a ehile. But thanks everyone for your help