Been having alot of problems with the engine feeling like there is a vaccum leak. Replace all the emissions hoses, valves, spark plugs & wires, fuel filter, oil change, O2 sensor and today replaced the MAF sensor because i got Code no. 34. I also got codes 42 & 44, but just replaced the O2 sensor. Anyone have any suggestions...been trying to work on this problem the last month and no progress.

 

check your fuel pressure. 44 means lean exhaust. fuel pump could be on the way out. or something as simple as the relay not working correctly.

 

How do i check the fuel pump pressure or tell if the pump is bad. I don't think it's been replaced since i've had the car, but at high speeds the car runs great, it's only at slow speeds when i give it a little gas and it really jumps and chuggs until i give it alot of gas and then it runs. Any suggestions? Fuel injectors have been cleaned too and i see no vaccum leaks?

 

if it's a tpi motor, then the test port is on the passenger side fuel rail in the rear. if it is tbi, then you'll need an adapter to install at the fuel filter to test it.