Q: Engine starts but won't idle

asked by on May 22, 2016

Looking to buy this Astros Van. It has been sitting unused for a year or more. Put in a new battery and it starts as long as you have peddle to the metal. Then the RPM's start to catch up to peddle to the metal so you can gradually let off but have to be very careful. If you take your foot off the gas, it dies. It will not idle. But the engine is running great, fluids are great and the A/C works. Just the gas peddle isn't doing something right. In the old days, it would of just been a carburetor adjustment. With these cars I have know idea. Am I looking at something big or small to fix this. Thanks for your help

My car has 36000 miles.
My car has an automatic transmission.

Car idle is rough Inspection $94.99 - $114.99 Get a Quote

The problem is most likely the fuel injection spider and fuel pump that needs to be replaced. The spider is inside the intake upper manifold and would cost over $1000 to get replaced. The fuel pump would be around $300 to $400. The fuel injection unit requires a high pressure from the fuel pump and the injectors are actually injector poppets that open the fuel to each poppet and the fuel pressure will push open the poppet and spray in the fuel. If the system is leaking fuel into the intake, then the regulator is leaking. This is why it runs at wide open throttle and not at idle. Have a certified mechanic inspect your idling issue, if you would like to have professional take a look at this in person.

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