throttle sticking 1997 1.8

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rake
Hey. They are NOT Training wheels.
Hey.  They are NOT Training wheels.
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Joined: Fri Apr 03, 2015 8:20 pm
Location: Auckland

throttle sticking 1997 1.8

Post by rake » Sun May 10, 2015 1:28 pm

The throttle is sticking for under half a second when i lift my foot off the gas peddle. the throttle is not actually mechanically sticking, i think it is a sensor or something. when i redline the car ill get a big puff of black smoke out the exhaust which might mean the engine is still getting fuel for a second while the throttle is closing. Ill clean out the maf first when i have time.

what dose everyone think? has anyone had a similar problem fixed?. cheers

marcellarius
I count 5-s in my sleep
I count 5-s in my sleep
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Location: Hamiltron

Post by marcellarius » Sun May 10, 2015 5:45 pm

It sounds like it's getting extra fuel and running rich.

A MAF engine measures the amount of air entering the engine, using the readings from the MAF and intake air temp, and uses that to determine the appropriate injector duration. A dirty MAF would typically mean it would under-estimate the amount of air, causing the engine to run lean.

It could be an issue with the O2 sensor -- this sits in the exhaust stream and measures the oxygen content to indicate whether the mixture is rich or lean. A dead sensor would likely look like a lean signal to the computer, which would make it add fuel to compensate.

Another option could be that a fuel source is being drawn into the intake. A common cause here is a failed fuel pressure regulator, this can allow fuel to leak into the intake, causing the car to run rich. Excessive oil consumption, or an automatic transmission fault can also cause a rich condition.

The engine coolant temp sensor (separate from the sensor that drives the gauge) plays a big part in determining the mixture. If it always had a very cold reading it could mean the car was always running in cold warmup mode.

IMO, check the easy things first:
* Air filter, inspect MAF. If the wires are caked up, carefully clean them (they can be easily damaged)
* Remove the small vacuum line from the fuel pressure regulator and check for any signs of fuel leakage. (put it back afterwards!!)

As your car is a 1997, it should have OBD2 (I think?). If it does, someone with a scan tool should be able to check for any trouble codes, and check the signals from sensors.
Last edited by marcellarius on Sun May 10, 2015 5:48 pm, edited 1 time in total.

Teamjelly
Need, more, 5-ing, time....
Need, more, 5-ing, time....
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Location: McLaren Falls

Post by Teamjelly » Sun May 10, 2015 5:46 pm

Give the idle control solenoid a good whack, and a clean
They're notorious for playing up.
Sticking feathers up your butt does not make you a chicken

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