Ok, at about 3000RPM I start to get some vibration from the engine up till 4500 when I shift. It is definatly RPM because it will even do it some in nutral. I don't take it up there very often, but want to make sure that when I do I'm not hurting anything. I have replaced the plugs, wires, cap and rotor. The previous owner said that he replaced the timing chain and my car only has 83K, but I'm not so sure he replaced it now. I think it is either valve timing or ignition components. I have tried ignition timing all over the place, with no luck. What do you guys think? I have also started to get some pinging when I use 87 gas. It never used to do that, so I have to use 93 now. Help me out guys..

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1989 Firebird Formula L03
Stock except for K&N, Flowmasters, Centerforce Clutch, MSD 8.5, and Accel Cap and Rotor. Much more to come.

 

A vibration could be the motor mounts. Weak or loose mounts could cause a vibration of the engine since it tries to pull itself out of the engine bay when unlatched. Check these for tightnes by doing the following.

Have a friend get in the drivers seat, keep it parked, or in neutral. While looking at the engine (w/ hood up) tell him to rev it quickly. While he is revving the engine, look for movement of the engine in the engine compartment. It will appear to try and jump out of the compartment. If this is the case, then engine mounts it is.

If not, see what a mechanic says.

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--Steve S--
1984 Trans Am 305 LG4, 5 speed
RPO codes point to Recaro version
Daily Driver, Flowmaster 80 Series

 

Holly *****, this thing just tried to jump up and kill me. I've never seen an engine move so much, so fast in my life. I don't know if that is the problem, but it will have to get done anyway. Thanks.

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1989 Firebird Formula L03
Stock except for K&N, Flowmasters, Centerforce Clutch, MSD 8.5, and Accel Cap and Rotor. Much more to come.