Car failed CA smog...Need some help

[nhra-trans-am]

I recently purchased an 89 TTA and I am trying to get it to pass CA smog. It failed due to the high CO level of the smog test.

The car was idleing a bit rough so I changed the spark plugs, pcv valve, fuel filter and serviced the fuel injection. However the idle is still rough. I was thinking that maybe the TPS sensor was to blame. Need some help figuring out what the problem is. TIA

 

[TurboBuRick]

Do you have a scantool?

 

[1BADDAM]

Hi CO is an indicator of improper air/fuel. Oxygen sensor? few other things.

It would help to post up the numbers. Also, as mentioned above scan tool number would help as well. I passed CA smog a month ago and a hell of a time as they lowered the maximums 30% accross the board.

 

[nhra-trans-am]

I do not have a scan tool.

Here are the smog readings

15mph HC max 80 ave 33 meas 34
25mph HC max 62 ave 24 meas 28

15mph CO max .52 ave .08 meas .02
25mph CO max .42 ave .06 meas .03

15mph NO max 549 ave 165 meas 544
25mph NO max 507 ave 142 meas 1300

 

[Scott89TTA]

is the car 100% stock ? If it has even a Stock/Street Turbo Tweak chip it will fail as the EGR is disabled. When I 1st got my TTA it was supposed to be 100% stock...if failed the MD emission test. Replaced the plugs & wires...failed again. I had about 4 months to get it tested again during that time I installed a test pipe/dump and found out the Cat was gutted. Installed a new cat and it passed with flying colors...took my cat back off and put the dump back on. Next time around put the cat back on and it failed...forgot to put the stock chip back in as I had previously installed a Turbo Tweak Street chip...put stock chip back in and it passed. Now I have Historic tags and no longer have to worry about getting it tested...lots of mods and more to come

-Scott

 

[Sweetwater GN]

I see you have high NO -nitrogen oxide, which is an effect of a faulty EGR or as Scott mentioned an EGR disabled because of an aftermarket chip. Check chip first, if its stock then check your EGR and solenoid.

 

[nhra-trans-am]

That is correct, I made a mistake when typing it. It had a high NO level. I am using premium 91 fuel.
I just bought the car, but as far as I know it is bone stock, including the chip. It appears to have a new cat on it though.

 

[Sweetwater GN]

Did you get it figured out yet ? Push up on the bottom of the EGR under idle and the car should start to stumble. Then your EGR and passages would be clear. Check the vacuum hose and the connector to the EGR solenoid. A valve is $45 and a solenoid is $65 at Autozone. If your REAL careful with it, the solenoid is always returnable if it doesn't solve the problem.

 

[Lee_Burough]

PM gofstbuick, he can help....His job keeps him up on these CA requirements, If anyone can help, he can. You need to get some scan tool numbers before a clear cause can be hypothesized.

 

[nhra-trans-am]

UPDATE
I replaced the MAF as suggested by a member here and the car is running a lot smoother. No more hesitation or stalling.

I do have one more problem. The car also failed the EVAP test. I replaced the gas cap, but I think there is more to the problem since they hooked up a machine to the gas filler that eliminated the cap during the test. Anywhere specific I should be looking? Thanks.

 

[357456]

Thanks for reminding me.

I need to go through the same eco ordeal really soon. The smog shop I use will pretest it for me.

This puppy will get a new roller cam first though.

Could someone please give me more to do on the weekend!:redface:

 

[357456]

Thanks for reminding me.

I need to go through the same eco ordeal really soon. The smog shop I use will pretest it for me.

This puppy will get a new roller cam first though.

Could someone please give me more to do on the weekend!:redface:

Mine passed today????: I thought what the heck and felt confident enough so I didn't pretest. Owner of the smog shop remembered me and gave me $20 off the fee. Must have done something right somewhere....

I'm still going to change the cam to a roller hyd. I'm tired of the ZDDP extra $ every oil change. I'll save what I have for my other cars.