My car is trying to kill me

Suzuki Esteem Wagon 1.6L 1999 runs good except when it loses power on the freeway and drops from the flow of traffic at 80mph to a death defying 40mph. The Suzuki mechanic Don changed the spark plugs & wires and adjusted the valves but it still does it. He can’t guess what the problem is. I need help before someone rearends me. I couldn’t sell it and let it kill someone else. Help!

It sounds very much like your car is not getting enough gas or enough air. Loss of power to this extent is seldom the result of bad spark plugs, wires, or valves out of adjustment. Your mechanic Don needs to go back to school and learn a little bit of trouble shooting!

Some of the causes could be partially plugged fuel filter, weak fuel pump, dirty air cleaner, and so on. I would go to another mechanic, since Don may keep changing things and draining your wallet without really knowing what he’s doing. All the while you are paying dealer rates, which are much higher than private, independent shops.

Wow this guy is a great mechanic-he changed the plugs and wires and he’s fresh out of ideas…sigh…

I’m going to suggest that the catalytic converter could be overheating, which will cause a sudden loss of power in extreme cases (It happened to me actually years ago). The more likely culprit is a fuel pressure problem. I’d hook up a fuel pressure gauge and take it for a ride on the highway and watch the pressure when the car does this. If it stays stable then it’s the converter or ignition system. Good luck.

I concur that you need a mechanic with more in his bag of tricks than just changing spark plugs and wires. Docnick and Dave G. have given you the most likely causes of the problem that you are experiencing, so this should give your mechanic (Don, or hopefully somebody else) some new avenues to explore.

In the meantime, logic would dictate that you NOT drive this car at 80 mph. If you drive at or slightly below the speed limit–in the right lane–you will be passed by most vehicles, thus reducing the chance of being rear-ended when you lose power.

And, if and when you lose power, immediately turn on your 4-way hazard flashers and try to steer onto the shoulder as soon as it is safe, until your power is restored sufficiently to try getting back into the stream of traffic. While the car’s mechanical problem is a potential safety hazard, your current driving style is making it more of a hazard.

Could this be a bad throttle position sensor? Just a thought.

Change the fuel filter. When/if your speed falls off, put the transmission into neutral (if traffic allows) and see if the rpm will zoom back to where it was. This will show if the ignition is cutting out, or not. If the rpm did go up, there isn’t enough fuel being supplied to the engine. It’s then time for your mechanic to do some troubleshooting (fuel pressure and regulator). The Haynes, or Chilton’s Suzuki repair manuals may have something on those checks.

Thank you each and every one. I just found these comments so I can tell you all how it turned out. I didn’t get killed on the freeway. I stay out there at 80 because the simis are going 80 in the slow lanes. I always use my flashers if there is any sudden slow down. I grew up in L.A. so I’m used to freeway traffic. I did go to an independent mechanic, Sam, who got it right away. It was the spark coil that feeds 2 plugs. I don’t take it to the dealer anymore. Sam closed his business and I’m with Allman Family now. He’s good. He has grease under his fingernails. Snorbelle Gilbertson 1999 Suzuki Esteem

I’m really glad to hear that it turned out well.
Thank you for getting back to us on the resolution of the problem.