I've seen before where the IAC sensor gets dirty. The IAC sensor is located on the top of the throttle body. If you refer to the throttle body as a clock, and picture the egde closest to the front bumper is 6 o'clock then the IAC sensor would be located at 12 o'clock. I think in a 02 GC it should have vaccum lines attached to it, and it's held down by couple of phillp's head screws. (I think) Take it off and clean it with throttle body cleaner until all the black gunk is out of it.
If you are not sure where the throttle body is, find the air filter box under the hood located on the driver's side lower corner. There will be a plastic "tube" going from that box to the top of the engine. Take this tube off and any part that connects to the top of the engine. You will then see the throttle body. It would also be beneficial to clean the throttle body out as well. (It only take a minute and it can only help your gas miliage.) You can find throttle body cleaner at any auto parts store, or Walmart or Target. Let me know if this helps, thanks!
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
you don't adjust the idle for any accessories
The idle is set for smooth running of the engine( normally 750-900 rpms with a drop of 200-300 rpms with an ac running so set the idle at the upper rpms and it will still be smooth when the ac is on without affecting gear engagement
your problem I take it is that when the ac cuts in the idle rpms drops and makes the engine run rough
This is normal as the ac compressor takes up to 5 hp to drive it
what you need is an electric controlled vacuum pot connected to the accelerator lever so that when you switch on the ac the power to the ac clutch energizes the pot and vacuum pulls the accelerator lever to maintain the set idle rpms
such an item is found on most early carby operated engines
run the fault codes as the ecm should compensate for the extra load on the engine when the ac compressor cuts in
there will be a rpm drop of around 150 rpms when it cuts in then it should settle back to normal rpms and when the ac cuts out the rpms will go up and the settle back to normal
anything else indicates a sensor fault.
high idle on starting is normal as it is the same as a choke being on. When it drops back it should be around 900. However tacos in cars are not real accurate under a 1000 rpms so have it checked manually with a rev counter. Run the fault codes to check for a problem.
Have it looked at by a dealer,iam not sure here but i think you have a vacumn leak like the feed pipe to the servo split but really you need a mechanic who works on these cars day in day out and they will go straight too the problem for you
driving in over drive mode actually is what gives the economy as the engine rpms will be around 300 less than direct drive . Lower rpms = fuel savings
OD should come in around 60 klm/hr and drop out at around 50 klm/hr. When you are accelerating hold the pedal in a set position and watch the rev counter (rpms ) and each gear change you will see the rpms drop and then build back up as the vehicle speed increases At 100klm/hr the revs should be around 3200 rpms or less but if over ( say 3500 rpms) then may be the OD is not coming in. One way to test a box operation is to find a speed shop with a dynomometer and test the gear selections against loads and engine rpms
You could have a clogged fuel filter, if you haven't changed it in awhile. You could have a leak in the intake system somwhere also. When you slow down, you get less power to the engine. It may need spark plugs and wires as well, if in need for a tune up.
Yes, the PCM for your vehicle's engine has a rev/speed limit seeting programmed into it. Most stock, non high performance/police package vehicles usually won't go above a top speed of 97MPH. if you were to rev your engine while it was in park or neutral, once the engine reaches the cut out rpm limit preset in the PCM, it will cause the engine to cut back, then it will rev up until it hits the preset limit, then cut back, and it keep repeating that pattern. It may sound as though you have a high rev ignition failure that sounds like waaa, waaa, waaa, waaa, but that indicates the PCM is doing its job.
being a fuel injected engine , there are many reasons this could be happening. from the top , lets check the Manifold Absolute Pressure (M.A.P.) sensor , as it is easiest. Find the MAP sensor , it has a couple a wires and a vacuum tube going to it and is on the firewall or fender support under the bonnet. Disconnect the wire harness from it (small plug with wires). If the engines RPMs drop to normal , replace the MAP sensor.