Check engine light keep coming on after repairs

keep driving

there are many systems that need to be ready for the obd testing. for example the catalyst has to be ready and the evap. system needs to be ready if more than one of these systems are not ready the machine will fail you at this time. then they will tell you to usually come back in a week or so after the vehicle has been driven and they will test the vehicle again for FREE of charge. also if you just recently had any work done and they cleared the codes from your vehicle this will delete your obd system ready lights, which will cause the same outcome.

Your mass airflow sensor and your o2 sensor may have failed?
Sometimes an after-market cold air intake system, could create problems like your having?

What does "not ready" mean?

A service technician will turn off the dashboard "check engine" light after most repairs. This resets the vehicle's emission system components to "not ready". The status remains "not ready" until the vehicle's computer has had adequate time to review the repaired component. This happens after the vehicle is driven for a period of time established by the manufacturer.

If the vehicle's emissions system status is "not ready" when it is presented at the E-Check station during the initial test cycle, a tailpipe emissions test may be conducted. If the vehicle is transferred to another test type, the vehicle must remain on the different test track until the vehicle passes the emissions test or receives a waiver. For example, if the vehicle undergoes an OBD II test and fails, it cannot be downgraded to a tailpipe test on a re-test; the vehicle must pass the OBD II test.

For initial and subsequent tests, if a dashboard light is on when the vehicle is presented at the E-Check station, the vehicle will fail the test.

How can the vehicle status be made ready?

When a vehicle is driven through its normal drive cycle, the computer reviews the emission control
system and if the vehicle was properly repaired, the system resets itself to ready. A normal drive
cycle includes operation at both cruising speeds and in stop-and-go traffic for up to a couple
weeks. This process should be followed before bringing the vehicle in to be tested.

Hello
Does the light ever come on while you are driving the vehicle? It is possible that the vehicle does not trigger the code on the key cycle when vehicle is connected to the OBDII scan tool (a cycle is the time from when a vehicle is started to the time the vehicle is turned off) you should however most of the time be able to check a vehicles trouble code history to see what may be turning the light on
Good luck
Chris

yes, OBD II, but not really a reset--just clear the code. A scanner can do this, but I would give it a day or so to clear itself. Car car will run tests while you drive.

The diagnostic test won`t tell you if there is water or what the problem is exactly.There is a trouble tree you follow when you get a code and it will tell you test a number of things by using a multimeter or test light.Some techs skip test or just replace parts and clear the code and sometimes the test do not come up with a failure.The usual problem with this code is water in the system and it usually requires replacing the injection pump.There is a service bulletin for this vehicle not passing the I/M test.The bulletin is 06-06-04-037.What you should do is go to the dealership and see if they can give you a copy of this bulletin so you can show it to the inspectors that are performing the test.Hope this helps.Good luck.

you will need to drive about 50 miles till the computer checks the system since it was reset. Your check engine light may come back again, if it does run a vacum test..

what kind of vehicle? what year? cause for about $40. or so, you can goto an auto parts store and get the OBD reader which conects to the computer under the dash in most cars and trucks anything prior to 1986 is OBD 1 anything AFTER SHOULD BE obd2 CHECK THE CODE to see what it tells you is wrong, that way you will know to be able to repair it. this will save you quite a bit of money to do it yourself then to be paying hourly rates to have a mechanic troubleshoot it all day. once you find out what code it is giving you for the check engine light, and get it repaired, you can use the OBD reader to reset the light.

Some vehicles require very specific drive cycles (called "drive traces" if you perform them on a road simulator or dyno) to activate certain self-checks like the catalyst and EVAP monitors. As a general rule, doing some stop-and-go driving around town at speeds up to about 30 mph followed by five to seven minutes of steady 55 mph highway speed driving will usually set most or all of the monitors. Consequently, if you're checking an OBD II system and discover that one or more of the monitors have not run, it may be necessary to test drive the vehicle to set the remaining monitors.

You should talk to a good emission tec, if this is not throwing a code, it is hard to say if that one of the components could be bad. O2,pump,convert, HeO2, every part of the emission system.

With a 1000 miles, and doing what is says above just before the test, and ending driving at the test
should be plenty. If it is not, you will have to have each emission part checked, or when the computer
is plugged in it might show a code that did not trip dash light.