Skip the auto shop - Our mechanics make house calls

Q: Car only starts when I pump the gas pedal.

asked by on

I replaced the throttle body and now the car will only start when I pump the gas pedal. What do I need to have fixed?

A: From this description it seems that there c...

From this description it seems that there could be separate issues happening to your Mitsubishi Eclipse. The three most common reasons I see for a car unable to start without pushing the gas pedal include; the throttle body gasket may have been installed incorrectly, the idle speed control screw needs to be adjusted and finally the throttle position sensor may need to be adjusted.

Every car may be made up of the same parts but they all install and work slightly differently. Sometimes parts aren't ready to install right out of the box so it is necessary to make certain vital adjustments to the part, in order to have the throttle body do its job properly. If this is the case, a trained professional can easily diagnose this concern on your car and determine if this is indeed the problem and will be able to make the adjustments necessary. While they are doing this, they can also inspect the idle speed control screw. The engine will need to be running, allowing the screw to be adjusted to run at the specified RPMs for that vehicle. Finally, with the throttle position sensor, a certified mechanic can adjust it by using the manufacture specs, it needs to be installed and clocked (turned a specific way) then a voltage meter is used to check the signal voltage (signal voltage is 5v and as you step on the gas pedal the voltage will vary from 1.5 up to 4.5 volts to tell the computer where the position of the throttle is and use his information along with other sensors to determine how much air and fuel are put in the engine) to ensure that the voltage specs are in the proper range.

As you can see, it is important to have a certified mechanic to look over this problem so they can diagnose which part may be failing and get you back on the road safely.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Oil leak near turbo

Hi there. Turbocharger seals are a common failure item as they do a tremendous amount of work and endure a lot of heat. The turbocharger also has oil lines running to and from the component that may have experienced the...

Q: Replaced Master and Slave clutch cylinders, feels like I have a clutch but can't put into gear while running.

You may still have some air in the clutch hydraulics, or you are having an issue with the clutch not fully releasing. This can be from the air in the system causing the clutch slave cylinder to not move far...

Q: Van squeaking and not starting all the time.

Assuming that the battery is good, yes a jump start will give it enough power to start the van. As for the overheating issue, since it is intermittent the most likely cause is air in the system. I would recommend...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.