hi all, i have a 95 z28. lt1 350. i picked it up incredibly cheap and i love it. but it has a stuttering problem. when i first start it in the morning for the first mile it is all that is man. i can floor it spin tires forever and get it sideways when it hits second, but after a mile or so it developes a stutter. drives fine going down the road and at idle but seems to do it alot under load. also it kinda smells like gas inside but very faintly. im fairly new to these engines. ive heard everything so far from the computer to o2 sensors, even the stupidly placed distributer/.. but if any one with real knowledge of these engines has a opinion i would love to know what you think. also it seems to get incredibly bad gas milage, about 13 mpgs. is that normal?? thanks in advance.

 

just a lil more info. after it warms up i cant get it to spin the tires, its not all there, just doesnt have power. it does backfire a lil bit at high rpms sometimes.

 

Check engine light coming on?

 

Have the ECM to see if it is throwing codes at your local Autozone or whatnot. The check engine light might be disconnected or burnt out. My Roadmaster did the same thing and it was the o2 sensors. The mileage went from 22 highway to 15.

 

This could also be caused by the opti or even the car needing a tune up, new plugs and wires

 

no service engine light. has had the plugs and wires changed. fuel filter changed. i was looking at it a lil bit just now at a local shop and the inside part of the ignition coil is loose, i can move it a bit. if it was the o2 sensor wouldnt it make the light come on. it comes on when i turn the key with the rest of the lights. if i unplugged the o2 sensors and the car didnt run any worse would that just be a good indication its the o2 sensors?

 

car only has 108k. dont know what else to say to try and help figure this out. i called a chevy dealer and they want 97 a hour just to diagnose! if i spent that and got nothing fixed my girlfriend will kill me and put me in the car and light it on fire. lol.

 

You need to get a scanner check for stored codes and see what the sensors are doing when the engine acts up. It will be cheaper than throwing parts at the problem. Unplugging the O2 sensors will force the PCM into open loop. When in open loop the PCM works off internal tables and does not look at sensors, so unplugging the O2s will prove nothing.

 

you can scann a 95 with a obd1 scanner. http://shbox.com/1/xraycable.jpg shbox is good. sounds like its doing it when it goes into closed loop. i would say its one of your sensors. test the intake air sensor, coolant temp sensor on the water pump, 02 sensor connections and readout, map, maf if you have one, check the evap system. heres a list of things to find most of the tests. 4th Gen LT1 F-Body Tech Aids also maf test, 2nd post, https://camaroforums.com/forum/4th-g...62/#post527062

 

I was out of country and junior called me in a panic. The 95Z was "knocking", stuttering, stalling at stop lights and backfiring. It ran ok when cold but in closed loop, it ran like crapola.

No codes were tossed but it had to be a sensor. Again, a 95Z.

I told him to get out the Actron 9145 and plug it in. My hunch was confirmed with a bad drivers side O2 despite the SES light never being lit.

A quick run to the parts store, $38 and 5 minutes later and junior was again happy with his dad and his car. (oh, with long tubes the O2's are right there and you don't even need to lift the car unless it's been lowered)

get it scanned.

and here's the rub. After he did it and called me back, he then thought it pertinent to mention that the car had been smelling rich the past couple of weeks prior and sputtered a couple times. ugghhhh