Can A Loose Air Intake Hose Cause An Engine To Run Rich Or Mess Up Oxygen Sensor Readings

Posted in Oxygen Sensors

My check engine light has been on and the dealer says I have a bad oxygen sensor. It’s a 2003 Caravan and I was under the hood last night to see how difficult it would be to change the sensor. They also told me my throttle body needed cleaning so when I went to check it out I realized they didn’t put the intake hose from the air cleaner to the throttle body on all the way. After I checked it and put the hose on correctly the check engine light went off after I drove about 30 miles. I put the two things together and wonder if the sensor is really bad or the readings were off because of a lose intake hose. Anyone have any advice on this?
Update- The mechanic told me it was the upstream sensor and it was reading 38% oxygen.

There are 6 Answers for "Can A Loose Air Intake Hose Cause An Engine To Run Rich Or Mess Up Oxygen Sensor Readings"

    1. Anthony S says:

      Yes it can. I know on most newer cars they have a computer on board that tells the engine to shut off if the hoses are not connected. I don’t think the that the oxygen sensor is bad, but if one is bad its probably the front one

    2. Colin M says:

      Yes, it can indeed. Didn’t look very hard, did they?

    3. bbking48507 says:

      a loose air intake duct is only going to cause problems with the air fuel mixture readings if the engine uses a Mass Air Flow sensor and the leak is after the maf sensor. the engine would be pulling in more air than the maf is sensing causing a lean condition(more air than fuel). Look for a sensor somewhere in the air intake system before the throttle body and after the air cleaner. It should have an electrical connector with about 3-5 wires. If it doesn’t have a maf sensor, then it is probably just coincedence that the light went of after you tightened the air duct. Either way, now that it is good and tight, monitor the check engine light. If it stays off, you’re good to go. If it comes back on, then you probably need a new O2 sensor.

    4. dodge man says:

      yes it can ,i own a repair shop,and have seen cars fail the smog test over this,the system was designed to run closed and if it has any of the hoses loose on it that can cause it to be too rich,it may need a new 0-2 sensor on it those things are supposed to be replaced every 35 thousand miles,but no one ever does it,most people don’t change them as long as there running good ,but you can take it by auto zone and have them look at it and see if it still has a bad sensor on it,they can scan it for free,and tell you this,good luck with it,i hope this help,s.

    5. Rudedude says:

      If your van uses an air flow meter ( Mass air flow sensor or MAF sensor ) yes this could be your problem. If it uses a pressure sensor ( Manifold absolute pressure sensor or MAP sensor ) then no. The easiest way to tell is if or the tube form the air filter box to the chortle body if there is a sensor with more then 2 wire connected to it . I’m a Gm tech so not familiar with the Caravan so sorry I’m not sure what your dealing with . Good luck hope I helped

    6. Mikael says:

      yes it can and happens alot to caravans.