Truck wants to die when I hit the gas

[Art]

1994. pushrod 4.0. Manual 5 speed. Truck sits there and idles well. when i hit the throttle she runs like crap, acts like it wants to die. Anybody have any clue why my truck might be doing this? this is my daily driver right now so I really need to get this fixed asap. Any and all help is greatly appreciated.
Thanks,
Art

 

[CheapThrills]

you check your fuel filter lately?

 

[Art]

you check your fuel filter lately?

Yea bro, fuel filter gets changed every august. A bit excessive I know but I dont want to be laying in the snow screwing with it in january. Oh an I did a fuel pressure test, tests fine.

 

[Mark_88]

Also could be a vacuum line...or not enough fuel pressure for the higher revs...

 

[adsm08]

How is the charging voltage? Check it while you work the throttle by hand. Voltage should go up or hold steady as engine speed increases.

You might also have a bad throttle position sensor or bad mas air sensor.

 

[Danni84]

do you have an EGR valve on your truck? the EGR valve on mine stopped working on mine and gave me that same issue. put a new one on and it was fixed. if you have one i would pull it off and look at it. A lot of the time they get gummed up with carbon.

 

[Art]

do you have an EGR valve on your truck? the EGR valve on mine stopped working on mine and gave me that same issue. put a new one on and it was fixed. if you have one i would pull it off and look at it. A lot of the time they get gummed up with carbon.

No EGR on this truck, Sir.

 

[kunar]

You might also have a bad throttle position sensor or bad mas air sensor.

This is what I would check...

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[Art]

How is the charging voltage? Check it while you work the throttle by hand. Voltage should go up or hold steady as engine speed increases.

You might also have a bad throttle position sensor or bad mas air sensor.

all i have is a little pocket battery/alternator tester it is testing voltage slightly too high on the battery and alternator.
I'm thinking about going and buying a maf and tp sensors to try, it certainly wont hurt it.
but.
I found an injector o-ring that was leaking fuel, put a new one on, and now im having different symptoms. At idle it will miss intermittently, if i whomp on it real quick and then let go it backfires. when i hit the throttle it still runs like crap but not as bad as before. If i gradually throttle up it will throttle up but something is wrong here she still aint happy and I need to drive it...

 

[black_demon69]

Is the cel on have you checked codes? Sounds like timing or its dumping alot of gas
Also check fuel pressure.

 

[Art]

Is the cel on have you checked codes? Sounds like timing or its dumping alot of gas
Also check fuel pressure.

CEL always on has been since I straight piped like 5 years ago and disconnected an o2 sensor.
fuel pressure according to harbor freight pressure gauge- 28 at idle, vacuum line attached, 38 at idle vacuum line removed.

 

[Art]

You might also have a bad throttle position sensor or bad mas air sensor.

I went and bought a MAF sensor, turned the truck on, and.....big difference. I can rev it up and everything I just drove it around. if i really whomp on the throttle and let go it will still backfire but it runs and drives thanks a million to everyone who posted on here to help me.

 

[Mark_88]

Cool...might want to check for codes if you haven't already done that...the CEL is indicating a sensor reading probably...and the backfire may go away once you put some miles on it...

Unhook the battery for about 20 minutes and then hook it back up...that should clear the codes temporarily if the situation hasn't been corrected your CEL will come back on and then you can read the codes...

I've read that parts stores (PEP boys or whatever) will check codes for free...

 

[Art]

Cool...might want to check for codes if you haven't already done that...the CEL is indicating a sensor reading probably...and the backfire may go away once you put some miles on it...

Unhook the battery for about 20 minutes and then hook it back up...that should clear the codes temporarily if the situation hasn't been corrected your CEL will come back on and then you can read the codes...

I've read that parts stores (PEP boys or whatever) will check codes for free...

Yea, they do I'll go up there and have them pull codes sometime this week

 

[Kowboy]

Hey Art; The back firing when you rev the engine, is probably unburnt gas exploding in the exhaust. Like you said, due probably from the straightened pipes and the removal of the O2 sensor. If your happy, I'm happy.