So here's the deal, my truck lacks power on the low and, and sometimes sputters if I don't feather the clutch when it is warm. When it's cold outside, or the truck has only been running for a minute or two, the truck runs fine. In the past I have gotten rich codes. For now there are no codes. Here's the list of stuff I've replaced:
Catalytic converter
Plugs(several times)
Wires
Coil packs
fuel filter (several times)
Fuel pump
Coolant Temp sensor
O2 sensor
Intake Air temp sensor: but the new one caused a code after two months, so I put the old one back on. Kinda weird, wonder if that means anything.
Supposedly mechanic checked the fuel pressure and it was fine.
I've also checked and cleaned most or all of the grounds I could find.
Air filter is clean
MAF reads correct voltage: .9V at idle
TPS also appears to read correctly.
I've also replaced all the intake gaskets, and have checked for vacuum leaks with starter fluid, cannot find any.
PCV valve is new.
New 195 degree thermostat.

Reset the computer also after each replacement part.

Each replacement seems to make the truck run better, and when the outside temp is below 60 the truck runs fine (even with AC on). It also runs mostly fine without the AC on. It's just bugging me that the truck won't accelerate without feathering the clutch from a dead stop in temps over 70.
Is there a way to test the fuel injectors?

i'm about ready to drive it off a bridge, i've put so much time and effort in solving this, and thought i was on the right track so many times.

The only other known issue I have is an aparent exhaust leak somewhere, or at the very least a bad muffler because it's very raspy.

 

Go outside with a spray bottle of Windex, start your truck, open your hood ( in total darkness ) and spray your plug wires and let us know how it went if your problem is there you will see very small sparks kinda like fireflys a real pretty blue in color.
and NO this is not a joke
Jim

 

was any of this work diagnosed with a scan tool or did you use a DVOM? Use a scan tool and graph the MAF, A dvom will find an obvious problem with MAF but it cannot switch over quick enough to find an itermittent problem. While your at it measure the O2 output voltage on a warm engine. 0-1 volt... low means lean high means rich. However it should have a steady swing which a graph would give you a good picture.
A good scan tool will make an obvious find for you.

 

I would suspect a fuel pressure problem. A rich code is set when the computer is detecting a rich mixture. It is trying to lean out as much as it safely can, and that still doesn't resolve the lean. This means that fuel is dumping into the engine beyond what the computer can control, or is being deceived into doing so. My guess is a ruptured diaphram in the fuel pressure regulator could be responsible, and may not show up on a fuel pressure test.

 

I forgot to update. I replaced the MAF and it fixed the issue. Now it is actually running lean, because way back when I took it to a mechanic, he tested all of the sensors and decided that it may have the wrong head on it, (as he determined head work had been recently done) and advanced the timing to compensate for the rich running symptom. I did more research and found out there was only one 8 plug head manufactured, so that could not be the issue. So I'm assuming that everything will be fine once I get the timing marks lined up again. It actually runs very good lean, but it's throwing a code anyway. Thanks for all the help! Don't trust a voltage test alone on MAF's.

 

K, you need to get that lean condition fixed before it burns something out.