1994 Camaro Z28 wont rev well
11-30-2011, 05:53 PM
#1
1994 Camaro Z28 wont rev well so i picked up this nice 94 Z28 with only 80k miles for cheap and trying to fix an issue. if you drive it around normally the car drives fine through all the gears up to about 55 or 60. Fuel pressure when motor off key on goes to 42 psi, motor on with line connected its 34 psi and with line off its 42psi. so the fuel doesnt seem to be the issue. i changed the Ignition control module, IAT, MAF and checked the wiring to the knock sensor to see if its pulling timing and everything checks out. at the moment i have the car torn down to disassemble the opti and clean/seal it and changing the wires and plugs. If that doesnt fix it I am leaning towards the cat to see if its clogged. it has a set of mid length headers and a coated Y pipe with a cat. anyone here have the same issue with their car? it runs fine but if you are in P/N and floor it, it wont go past 4500 rpm. and its just weak if you give it throttle. it doesnt miss or anything which tells me the plugs are fine. any input guys?
12-01-2011, 12:43 PM
#2
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sounds like you got it all covered... running rich or lean? compression? air/fuel filter... bad pump? i had a bad set of o2's on mine when i first got it swapped them out and it was 100% again.
12-01-2011, 12:57 PM
#4
the SES codes rich AND lean. fuel pressure is steady at 43 psi. fuel and air filter are both new. compression is 140+ psi on each cylinder. O2s are brand new. as of a couple days ago. i took out the opti and cleaned everyhing up as well as installed new plugs/wires and now it wont run at all. no spark bc fuel is definately there. so now I am going to replace the Opti and coil today in hopes that will
12-01-2011, 08:43 PM
#7
alright well i jumped into a pile of s*** today. so I replaced the Opti, Ignition Module, AND coil today and all components checked good with a multimeter. so here is the issue. I have NO spark. none. i did all the checks and I am getting voltage to all the pins and everything seems to be operating fine. but no spark. the Opti is brand new (used the oil cap and rotor). I had a Formula that had a similar issue. the cap was junk. without the water pump it would run great. but when you put the water pump on it wouldnt run at all. the cap was shorting on the water pump. anyone have any suggestions?
