Jump to content

Failed emission! '93 Lumina Z34


Laveen Z34

Recommended Posts

Good Folks of W-Body,

Failed AZ emission (CO only by 0.12 - damn) but passed CA emission 2 months ago. Drove it for 4 hours with no problem. After emission I saw a leak coming out of R side radiator (as you're facing the car) inlet tank. This was the second time. First time was during the trip and when I got home, water gushed out like someone turned on the spicket. Replaced the radiator - no more leak. Then, all hell broke loose. After flushing and refilling, started engine and high RPM started around 3000 with hiccups/hesitation like presentation, will go down after engine warms up after radiator fan comes on to cool down engine, needle will get to almost last white line but never RED. LIMG? Any special way of replacing this? should I go ahead and replace the O2 sensor since I'll be taking it apart? I have a real good friend/mechanic that will do the LIMG, plenum gasket, water pump, cam seal, timing belts, and replace a vacuum line that goes along the back wall for 600.00+, good or bad? or should I spend my next two weeks in between work schedules to do it myself. Labor kills!!! I am not a mechanic but knows enough and can follow directions, I need you expert advise.

Link to comment
Share on other sites

Sounds like you didnt get the cooling system bled correctly which is causing overheating. As for the high idle did you disconnect the battery when changing the rad out?

Link to comment
Share on other sites

Yes I did disconnect the battery. Is there any special way of bleeding the cooling system - Haynes didn't tell much except, keep radiator cap off, heater on hot and fill until level is visible at the bottom of the rad neck then place cap? Any advise is greatly appreciated.

Link to comment
Share on other sites

There's two bleeder screws on the DOHC 3.4 coolant tubes. They both need to piss coolant instead of air.

 

If CO is high, the fuel mixture is rich. What's the block learn and integrator numbers, what temperature does the engine think it's running at, and what's the O2 crosscounts?

Link to comment
Share on other sites

My Friend,

You sound very knowledgeable about the problem I'm having. Can u tell me exactly what do you mean for each one of your question? I really appreciate all the support and will help me alot about learning how to upkeep my vehicle. Anyway, besides the emission problem, what's your take on a high RPM on cold start around 3000+ for at least 5 minutes or so and when the fan turns on the first time as the temperature rises to about 210-220, RPM goes down to about 2000 then I can shift to reverse and RPM goes down to 800. do you think I have a blown lower intake? Can you read my initial post and please tell me what you think.

Link to comment
Share on other sites

Can u tell me exactly what do you mean for each one of your question?

 

What's the block learn and integrator numbers, what temperature does the engine think it's running at, and what's the O2 crosscounts?

Connect a scan tool to the vehicle, and the tool should provide tons of information. Block learn and integrator should each be 128 or close to it; higher numbers indicate rich command, lower numbers indicate the computer is trying to reduce fuel from the baseline. The computer will output the engine temperature; if the temp is way low, that'd explain the rich mixture. O2 crosscounts indicates how many times the O2 sensor goes from rich to lean, or from lean to rich. A low number indicates that the fuel mixture is way off, or the sensor is getting lazy.

Link to comment
Share on other sites

Connect a scan tool to the vehicle, and the tool should provide tons of information. Block learn and integrator should each be 128 or close to it; higher numbers indicate rich command, lower numbers indicate the computer is trying to reduce fuel from the baseline. The computer will output the engine temperature; if the temp is way low, that'd explain the rich mixture. O2 crosscounts indicates how many times the O2 sensor goes from rich to lean, or from lean to rich. A low number indicates that the fuel mixture is way off, or the sensor is getting lazy.

 

its a 93 so any scantool data access may be very limited,should have your O2's like schurkey said, but take a look at your fuel trims if possible also

Link to comment
Share on other sites

its a 93 so any scantool data access may be very limited,should have your O2's like schurkey said, but take a look at your fuel trims if possible also

Data access may be very limited???

 

You've never worked on a Chevette MIN-T system.

Link to comment
Share on other sites

Data access may be very limited???

 

You've never worked on a Chevette MIN-T system.

 

80 baud FTL.

 

a 93 Z34 is a $DF setup, it has plenty of info packed into it's stream.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...