mchale2020

Hey guys,

I've got a 1997 Z28 and it's making me and my friend wanna' cry.

The car is running rich and causing the motor to slightly miss. We knew injectors #3 and #7 were stuck open, so we replaced both injectors. Today, we replaced the spark plugs for the respected cylinders and installed a new o2 sensor on the driver side. It was obviously bad b/c the tip was resembled charcoal. We tried to replace the passenger's side, but the sensor wasn't coming out with a ratchet.

The car still runs poorly and the SES light flashes occassionaly. We're certain the fuel pressure regulator is ok, we checked the opti and it's giving us spark, and we're running out of ideas. The screen that sits in front of the MAF was gutted and the PCM still has its stock tune. The air pump was ditched by the previous owner as well as the factory exhaust in favor of a Borla set-up. So, most of the emissions equipment is absent.

Tommorrow, we're going to try and scan it with Tech2 and see what exactly is going on inside the motor. We know the car is still running rich.

I just want to see if anybody has any suggestions on what is wrong with my car.

Thanks,

~Jordan~

Formula350

iTrader: (3)

Sounds like it's still the O2. Being a 97 (OBD2) it'll log what the codes are, even for flashing quickly.

See if a friend has a laptop, ALDL and some data logging software.

Ralls

iTrader: (32)

First off, you should replace all the plugs, not just two. The car will try and compensate for the missing cylinders and may foul out the other plugs.

A flashing SES light indicates a misfire bad enough to destroy an emissions device (cat). Figure out what the code is before we start guessing stuff.

Slowmaro95Z28

sounds like o2

C5042081

iTrader: (5)

had the same thing happen, had 2 injectors stuck and almost a 3rd, my plugs had less then 100 miles from new, all 8 of them were fouled pretty bad....change all 8 and go from there.

mchale2020

*UPDATE*

Well, we finally got around to scanning my car with tech2. 3,6, and 7 are missing in an unpredictable fashion still, and we pulled the plug out of 3 and it is not fouled. What's weird is that 3 and 7 miss in a really weird way b/c sometimes when we started the car, 3 would hold steady and 7 would miss like crazy, then it would be vice versa. Therefore, we think the Opti is going bad.

The o2 sensors checked out okay.

Anyway, any thoughts?

Ralls

iTrader: (32)

I would put a test light on each injector to watch the flashing to see if it's the injector wiring. Then use a spark tester to make sure each cylinder is getting correct spark. If the spark is erratic, then work your way to the opti.

mchale2020

Dude!!!

I totally forgot about trying a timing light!!!

Maybe I can get my hands on one soon so we can get around to that.

Assuming my problem's source is a the Opti, would you even consider a cap and rotor kit or just the whole she-bang?

Plus, since the water pump has to come off anyway, I was thinking about getting a new one while the car is apart. Since I don't care about building a fast car (just a reliable one) what do you guys recommend?

Thanks a lot!!!!

Ralls

iTrader: (32)

We don't have Timing marks on the harmonic balancer if that's what you're referring to.