Hello everyone I recently purchased a 94 z. I also have a problem with it at high rpm even in 1st gear it pulls very slowly after 4500 and you can feel a huge power drop. Ok heres everything I know about the car, 157k new fuel pump, regulator, and filter. I put all on myself. Fuel pressure is 38 at idle 46 WOT. 52mm tb, underdrive pulleys. and I think a 160 degree thermostat haven't checked that one out yet think it might be sticking a little though going to change it tomorrow.

Any help would be appreciated.

 

car runs great up to 4500 doenst use oil no smoke or anything

 

Could be your Optispark distributor, located under the water pump and behind the damper pulley. These are known to go out. Judging by the miles on your car that may be the culprit. Check your water pump for leaks, that will destroy your Opti in no time. Also use the search engine on this site, you'll for sure find many many posts on this topic.

Congrats on your new purchase and welcome aboard

 

Ok as long as I have to take the air pump off to check the opti, what do I need to do to get rid of it and the egr.


Have already email pcmforless about a program to do away with them.

 

check plugs and wires, coil, and ignition module before you start tearing into your opti. My car with 74k miles started missing at 5.5k, then 5k, then soon enough it would hardly start and you couldn't go over 3.5k because it would just pop and bang and missfire. I replaced coil and ignition module, no fix. Then bought a new set of lifetime warranty autozone wires, all I did was change the coil wire and my car started right up and now revs happily to redline. Even with 74k, when I took my coil wire off, the boots were rock hard and the connectors were literally dust. Just for kicks I pulled on each side of the wire and it snapped in two with very little effort. I see way to many people just jumping to the opti conclusion, make sure you go through the cheap easy stuff first.

Also your motor has 157k, worn valve springs could cause valve floating, but that's a pretty low rpm for valvefloat i think.

Using premium fuel? My engine gets a bit of knock retard (-10 deg) at 5k+ and the engine takes pretty big dive. Mine's from an exhaust leak, but using poor gas could give you retard. I doubt this is the problem though, it'd be more sporadic.