distributer is new as is most all of the components since i rebuilt it in 2011.
the timing is spot on.
why do you say its obd 1.5
gm dealer tells me it obd 2, im inclined to believe it since i bought it from them.
and i have a 2000 as well. cant help it i love my gm toys.
i have 7 of them.

 

Check the edit in my previous post.

Your 1995 does not have a Mass Air Flow sensor, your 2000 does. 1995 has only two oxygen sensors, the 2000 has 3. 1995 has one fuel injector, 2000 has 6. The 1995 is not fully OBDII compliant, guaranteed

"Timing is spot on" (Timing lights are obsolete on this engine). Have you checked camshaft retard since the distributor was installed? Have you performed the crankshaft position sensor relearn since the engine was installed?

 

you said the fuel return line could be leaking into the plenum.
if it were leaking i should see an increase in my oil level shouldnt i, but the level is not rising and its free of any smells other than oil.
so how would it cause the fuel to come in contact with the plugs ???

 

crankshaft relearn was done by my friend who is my snapon dealer.
and im not suprised the dealer was wrong they lie to make money.
salesman go to school to find new ways to lie.

 

In the lower intake manifold there are two small holes that lead to the back side of the intake valves on cylinders 3 & 4, (center cyls on each bank). If raw fuel leaks enough in the plenum, it will drain through those holes to reduce the possibility of explosion within the plenum. If enough fuel drains down when the engine is off, it will seep past the rings and into the crankcase. Now, IF the return line is leaking, it will be under low pressure when the fuel pump is running, less pressure when the engine is running too. When the engine shuts down, only the fuel in the line inside the plenum will drain out, maybe a tablespoon full. It may or may not be noticeable on the oil dipstick, but plugs 3 and possibly 4, will probably be wet with fuel.

Have your Snapon guy check camshaft retard with that same scan tool.

 

i really miss the days when it was a simple thing to buy a car, you went to the dealer and filled out an order form and they built your car.
my olds was built that way but i had to travel from utah to las vegas nevada to get it, because my gm dealer wouldnt let me order my car how i wanted it.
hes no longer my car dealer.
i also miss points and condensor ignitions. soo simple to work on.

 

Don't get frustrated... I know what you're talking about though, I've been a tech since the early 70's. The onset of computer controls has made it MUCH easier to diagnose them. Seriously, have your Snapon guy stop by, I can explain how to check, and adjust if necessary, camshaft retard... makes a huge difference having it correct if it's off. It can be off as much as ~27 degrees and NOT set a DTC, but fuel mileage will be out the window! Take care, gotta be to work in 5 hours, probably be back on tomorrow.

 

all my plugs were wet with fuel.
i will check with him about the tests and settings,but since the engine has ran fine since my rebuild, why would i have to check those now.
i could list all the new parts i put in the engine. but i will just say its built better than factory specs and if i could have i would have gone so far as to replace the bearings with rollers as well.
my 2000 has nothing on my 95.
the 2000 has roller rockers and roller lifters. my 95 got a double roller chain and gears,roller cam and lifters and roller rockers. when shes running shes smooth as soft butter. my friend helped build it. he builds race engines at his machine shop. i have alot of money in this motor. thats why im so frustrated with this thing right now. it was running perfect till this tuneup crap started.
its only got about 1000 miles on it. hopefuly you can see why im mad at it.
its my sons only car now since his ss cobalt got ruined by his neice.