Modified and Rebuilt TBI now won't run

[Szil66]

Hey guys,

I need some help.. This past Saturday I did the ultimate mods and put all new gaskets in my TBI. Put it all back together and it started up and ran fine. Started it on Sunday and drove it around town, no problems. Monday morning I got to start my truck and it has a terribly rough idle, I attempt to leave for work and when I gave it throttle it would just cut out and try to die so I limp it back home.

After work I go to the parts store and buy a new IAC. Start up my pickup, it now has a nice smooth idle. I take it out for a drive and still same thing. So I got back to the parts store and buy a TPS. Take it for another drive and same thing.

I don't want to keep throwing money at it but it's my daily so I need to get it figured out. I get a code after driving for so long but it's code 44 which is O2 Sensor (Lean Condition) which makes sense because the engine acts like it's not getting fuel.

The rebuild kit I bought didn't include a new fuel pressure regulator but I am not sure that is the problem either. I have also read that it could be the EGR solenoid and to unhook the vacuum line to see if it runs better and sometimes it may but then they say they replace their solenoid and they still have the problem.

It seems like multiple cylinders are misfiring so it almost makes me think it could be an injector but I am not sure.

When I am driving, if I put the pedal to the floor it'll get some power but still not 100%.

 

[90halfton]

Check wires to injectors to make sure ones not pinched and cutting out. Putting the air cleaner riser ring thingy on it happened to me one time. Same thing you're experiencing was the result.

 

[Szil66]

Nope, wires looks good, I just went out and pulled the air cleaner off and the riser and started it to watch the injectors and they both look like they are spraying well

 

[Szil66]

Replaced the fuel pressure regulator today still no change. It only happens under loan, if it's in neutral and I rev it, it runs just fine. But when I start to let the clutch out and give it some gas it wants to cut out.

 

[J_lope82]

Check your fuel filter and fuel pump

 

[OutlawDrifter]

See above, sounds like a fuel supply issue.

 

[Szil66]

I replaced the fuel filter which was definitely passed due, however, it wasn't the problem. It could be my pump but I don't have a gauge to check it.

I drove it again last night after replacing the fuel filter and there was no change, although my SES light didn't come on after driving it for awhile.

I don't have the time or money to keep putting into parts I don't need so I took it to the shop. Thanks for the replies. I will let you know what they find.

 

[Szil66]

Dealership concluded that is was the fuel pump, was only pumping 5psi.

I guess I've never heard of a fuel pump doing that, I figured it would either pump or it wouldn't pump. Also I was too caught up thinking it was because of something I did while rebuilding the TBI.

Glad its fixed, thanks for the help guys.

 

[90halfton]

Glad ya got it fixed. Sucks when something unrelated with what you're doing breaks, coincidence is s *****.

 

[J_lope82]

Dealership concluded that is was the fuel pump, was only pumping 5psi.

I guess I've never heard of a fuel pump doing that, I figured it would either pump or it wouldn't pump. Also I was too caught up thinking it was because of something I did while rebuilding the TBI.

Glad its fixed, thanks for the help guys.

I'm glad you got it fixed. From my experience that is a common symptom of a fuel pump gone bad.