Edmunds Answers

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  • avatar karjunkie 05/09/09 10:17 am PST

    I suspect either a vacuum leak in the hoses or the intake manifold, dirty MAF sensor or a weak fuel pump. Check all vacuum hoses for a crack or loose connection. Spray starter fluid around the intake manifold gasket at different spots to check for vacuum leaks. If the engine surges from idle as you spray a particular spot, you have a leaking intake manifold at that point. . Clean the MAF sensor wires in the intake plenum with CRC sensor spray. Don’t touch the wire, just spray until the wire is clean and shiny. Test the fuel pressure at the fuel rail. Position the ignition switch and the A/C system in the off position. Install a fuel pressure gauge to the vehicles fuel rail or fuel pressure test port. Confirm that no leaks are present, and visually verify the PSI reading on the gauge with the ignition in the on position. On your vehicle the pressure must be 60 PSI, plus or minus 5 PSI. One other thing to check and clean is the idle air control valve. At 97K miles, it is probably pretty gunked up with carbon deposits. Cleaning the IAC is easily done with a toothbrush and spray throttle body cleaner after removing it from the throttle body which is easily done by just removing the two torx-head screws that hold it in place. Once it is clean, together with the hole the IAC’s plunger fits into, use the remainder of the TB cleaner to clean out the inside of the throttle body per the instructions on the can. Good luck and let me know if you have any follow up questions!

Answers

  • karjunkie 05/09/09 10:17 am PST

    I suspect either a vacuum leak in the hoses or the intake manifold, dirty MAF sensor or a weak fuel pump. Check all vacuum hoses for a crack or loose connection. Spray starter fluid around the intake manifold gasket at different spots to check for vacuum leaks. If the engine surges from idle as you spray a particular spot, you have a leaking intake manifold at that point. . Clean the MAF sensor wires in the intake plenum with CRC sensor spray. Don’t touch the wire, just spray until the wire is clean and shiny. Test the fuel pressure at the fuel rail. Position the ignition switch and the A/C system in the off position. Install a fuel pressure gauge to the vehicles fuel rail or fuel pressure test port. Confirm that no leaks are present, and visually verify the PSI reading on the gauge with the ignition in the on position. On your vehicle the pressure must be 60 PSI, plus or minus 5 PSI. One other thing to check and clean is the idle air control valve. At 97K miles, it is probably pretty gunked up with carbon deposits. Cleaning the IAC is easily done with a toothbrush and spray throttle body cleaner after removing it from the throttle body which is easily done by just removing the two torx-head screws that hold it in place. Once it is clean, together with the hole the IAC’s plunger fits into, use the remainder of the TB cleaner to clean out the inside of the throttle body per the instructions on the can. Good luck and let me know if you have any follow up questions!

  • 02silver1500 05/31/09 2:37 pm PST

    FYI FOLLOWUP.

    After trying the above things to no avail. Took to dealer and found it to be the catalylic converter being plugged. They replaced & running great. Cost about 800$.

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