Red Mnster Z

After swapping my new motor into my 93 Z28, motor is from a 94 Z28, I got the cam reground to LT4 Hot Cam specs and adjusted the valves to zero lash, and got it started the first time, it started right up and ran fine without any problems until one of my fuel lines popped of the connector and then wouldn't start after that. I was able to get it started again but it was and still running rough and just shuts off without touching the throttle. The motor won't stay running while idling. The ecm threw a code saying the MAP sensor but I replaced it with a new one, and still the same thing. I also replaced the lifters and push rods with new ones since one of the lifters was bad and a push rod snapped in half. Adjusted the valves again to zero lash again and still the same thing, motor running rough and won't stay running while idling unless I'm on the throttle. Any ideas of what it could be?

Optispark, spark plugs and wires, MAP sensor, ICM, Coil are all brand new!

tricked94camaro

iTrader: (1)

hows fuel pressure?

Red Mnster Z

fuel pressure is where it should be, about 44 psi for my car.

THADD

iTrader: (12)

I had a similar problem and it was because my car was out of gas. Needle was reading incorrectly. I would really check everything with the fuel, fuel pressure, pump, etc...

Red Mnster Z

could it be the IAC (Idle Air Control) that is the problem? the motor doesnt want to stay running at idle because it is not getting air, but when i touch the throttle it runs but really rough. ive been researching this problem and i think i have come down to it being the IAC.

Fazz73jr

iTrader: (3)

Push rod snapped? ? I'd check for valve damage. Do a compression check. No reason a push rod should snap like that with such a mild cam.

quik95lt1

iTrader: (7)

yea what he said^


how did you install the cam? is the valve timing right it sounds like its off and you had some valve contact and tossed a pushrod....and will also make it run like garbage.....

Red Mnster Z

me and my dad installed the cam the correct way. after the cam was installed, all the lifters and push rods were put back in and then we adjusted the valves to zero lash. the first time we started the motor up, it started right up w/ no problem until we had to shut it off after about 30 seconds of it running because a fuel line popped off. then it would stay running like it was doing the first time we got it started. it was then after several attempts to keep it running, a rocker arm started ticking and found out that my #7 cylinder intake rocker arm was really loose. we then readjusted to valves again and tried starting the engine hoping that it was fixed but still doing the same thing until i took the valve covers off again only to find my push rod was broken and in the valley of the engine. the new roller lifters and push rods didnt seem to solve the problem. now im coming to the conclusion that the IAC is bad and need a new one.

kahiwamckeague

Hey guys, I got a 1993 Chevy Camaro V6. I was driving home when all of a sudden it dies on me, I immediatly smelt gas. I was looking at the engine and noticed that the fuel lines had popped off in two areas. Is this a quick fix maybe just clamps or is it more serious? I was able to get the lines connected and was able to get home but worried it will do it again like on the freeway. Suggestions and input appreciated.

Big Al

iTrader: (1)

I'd go back to the "push rod snapped" part of this. Something is dead wrong. How did you adjust the lash?

Al 59 Z28

WS Sick

Valve lash is off, I'll bet if you adjust the factory lifters to a full 3/4 turn past "0" lash it cleans up.