Backfire at high RPM, injectors?
Thread Starter
Joined: Dec 2007
Posts: 1,885
Likes: 1
From: Southern California
Backfire at high RPM, injectors? My car is a 94 Z28 Camaro. I have replaced the Optispark and water pump(to be safe). I bought the car not running. It is a 6 speed and runs good but if I get on the throttle it starts to backfire and pop above 4k rpm and seems to only really do it after it warms up.Could this be maybe a clogged injector or has anyone had a similar problem?
I had a 96 Z28 a while ago but never had this problem. I d like to fix it as I am trying to sell the car...need more money for my WS6.Thanks for the help guys it is greatly appreciated.
I had a 96 Z28 a while ago but never had this problem. I d like to fix it as I am trying to sell the car...need more money for my WS6.Thanks for the help guys it is greatly appreciated.
Im thinking around 33-37 NOT 100% SURE though. the most important thing is to see if it drops off sharply when the motor starts acting funny. Also check the fuel filter b4 u go to the trouble of hooking up a fuel pressure guage. It may be very old and clogged and could be the problem.
On The Tree
Joined: Feb 2006
Posts: 161
Likes: 0
From: Red Oak,Texas
hey buddy i had the same senerio and it was the ignition contol module. its on the front of the driver's side head. but i think i replaced the coil to at the same time so im willing to bet that its one of the 2, leaning more towards the icm. i think it was around 150 for the module though 
. but the coil was around 20 i belive. so maybe you would do that first.
. but the coil was around 20 i belive. so maybe you would do that first. Thread Starter
Joined: Dec 2007
Posts: 1,885
Likes: 1
From: Southern California
Great...Thanks Alot both of you.
Yup...replaced fuel filter already...I was sure that would do it but it can never hurt.
I actually have a 93 LT1 from a vette in my garage im going to swap into my 55 Chevy truck...Ill just have to rob some parts and see if it changes, hope the parts are the same.
Thanks Again so much.
Yup...replaced fuel filter already...I was sure that would do it but it can never hurt.
I actually have a 93 LT1 from a vette in my garage im going to swap into my 55 Chevy truck...Ill just have to rob some parts and see if it changes, hope the parts are the same.
Thanks Again so much.
Thread Starter
Joined: Dec 2007
Posts: 1,885
Likes: 1
From: Southern California
Well the corvette module is different, as soon as I started the car the SES light came on. However I did find a small vaccum port just below the coil with nothing connected to it. It is between two rubber hoses coming from the smog pump to the pipe on the exhaust manifold. Once I plugged it and put the Camaro coil and module on it ran great!No backfire, lots of power. Parked it at the local speed shop while I picked up parts for my WS6 and on the way home(less than a 1/4 mile) the SES light comes on.
Now all of a sudden it idles rough.Throttle response is poor, SES light still on. At one point I fired it up and it idled at 2k rpm. Now if I shut it off and restart it the SES light is off, after about 30 seconds I hear a click under the hood, SES light comes on, and two seconds later both fans come on, and all the while never going above 175 degrees. Any ideas?
HELP!
Thanks for the advise.
Now all of a sudden it idles rough.Throttle response is poor, SES light still on. At one point I fired it up and it idled at 2k rpm. Now if I shut it off and restart it the SES light is off, after about 30 seconds I hear a click under the hood, SES light comes on, and two seconds later both fans come on, and all the while never going above 175 degrees. Any ideas?
HELP!
Thanks for the advise.
