Kevin84Z28

iTrader: (3)

After putting on a set of headers I'm having some issues with my rebuilt CCC Qjet.

1. Idles at 600 rpm but runs kind of rough.

2. Loud backfiring through the exhaust on deceleration.

3. Very Strong odor of gas from engine compartment when the car is parked.

4. Hard starting (like a dead battery) when engine is warmed up.

I checked the electric choke with a test light and found that it's getting voltage even after warm-up, I don't know if thats normal or not.

I remember dropping the O2 sensor a few times when I put the headers on, could that have damaged it?

Rolling Thunder

Despite what you would imagin concidering o2 sensors are exposed to such high temps they are actually pretty delicate. Might want to try swapping it.

Kevin84Z28

iTrader: (3)

I think I will replace the O2 sensor, Thanks.

scooter500

iTrader: (1)

my car will backfire if coasting in 3rd. doesn't happen in drive.

naf

iTrader: (7)

How far down is the O2? I had to go to a heated O2 with my headers, it was taking too long to warm up. Is the Idle Speed Solenoid operating correctly? Should help with the backfire on decel issue some. Any change to the timing recently that could be contributing to a hard start? Were any cables disconnected/reconnected with the header install?

Kevin84Z28

iTrader: (3)

Shorty header so the O2 is pretty close to the heads, about 18". I don't know how to check if the idle speed solenoid is operating correctly. There has been no change in the timing, and no cables were disconnected. I'm assuming you mean throttle cables? I had to remove some wiring i.e. temp gauge, o2, fan switch...etc.

naf

iTrader: (7)

O2 is probably close enough, mine is in the Y.

Your driveability issues are most likely due to failed O2 or bad carb adjustment. Installation of headers WILL lean the mixture and may require re-adjustment of IAB/Dwell. Do you have a dwell meter or scanner to check the carb adjustments? I'd do that first before buying a new sensor.

Your hard start issues could be related to heat soak from your new headers, especially if the starter had some age to it. You can try to clean your cable connections, replace positive cable to starter (new one at AZ is like $8 and is larger than the stock cable that was on an 87 I have), install some heat shielding or replace with an LT1 style 'mini-starter'.

The idle speed solenoid should engage during certain decel conditions to prevent the throttle from slamming shut. This reduces backfiring and stumbling. Your backfire is most likely related to maladjusted carb-either from out-of-whack IAB settings (dwell) or faulty O2.

Oh and , choke coil will continue to receive 12 volts whenever the engine is running. That's normal.

five7kid

iTrader: (14)

The idle speed solenoid is adjusted with AC on. Verify it has power when AC is on, and that it is pushing the throttle open slightly. Then set it to the proper idle speed. That's all it takes.

Kevin84Z28

iTrader: (3)

I'll replace the o2 and check the ISS and report back.Thanks