surging at cruise speed

[wvragtop]

96 cobra it seems to Surge at Cruise speed. I have a wideband on it also. It doesn't seem to be showing correct AFR at times. Sometimes it's above 18 + off the scale. Not really sure what direction to go or where to look first. I have replaced my O2 sensors when I installed my long tube headers. I did have a nitrous backfire one time and I replace my mass airflow sensor as it blew the screen out of the housing and I thought it could be damaged. I was wondering if the intake air temperature sensor could have something to do with this. I plugged in my SCT scanner and was data-logging earlier. I'm not sure but I think it shows up as IAT on the data log. It's about 20 degrees outside here and it was showing around 90 to a hundred when my car was idling. Is that the actual temperature it's giving me or some other value on the Data logg

 

[Roots-type]

Did you replace the screen in the maf after the backfire? If the car was tuned with the screen in, you need to run the screen.

 

[wvragtop]

I replace the whole mass air flow sensor and housing with a new screen in the housing

 

[98 svt]

Any chance it's as simple as a TPS?

 

[wvragtop]

The check engine light does come on but it says something O2 sensors I believe. But they are new. I I checked them with a meter they checked okay

 

[Roots-type]

I'd pull the plugs and have a gander next. And make sure you didnt swap the o2 sensor harness from side to side on the new sensors.

 

[Blown38]

Check for exhaust leaks. If you are getting lean O2 codes and your wideband is showing lean you could be sucking some air. You could also look at the plugs and see if they are black/rich from the EEC adding fuel because of exhaust leak.

You can also get lean codes if your intake manifold is leaking from the back fire.

 

[wvragtop]

I never could find any vacuum leaks I sprayed either all over it. My wideband is in the header that has the slit tube for the steering shaft. It is possible that it might show a little lean right there. I'm going to swap it and the other header soon. I don't know if I could have swapped O2 sensors side to side not sure if there's enough room in the harness to do that. But I may just walk them and see if there is. I was really curious to know if that air temperature sensor in the intake tube could affect the tune