[johnvosh1986]

I sit at a stop light for about a minute or so (one cycle) and I am at the stop line. When the light turns green I push the accelerator pedal and I will get a slight hesitation before I start accelerating. There has been 3 or 4 times where it almost sounds the car had a small backfire or possibly a small pop coming from the engine. I am not doing 100% acceleration, I'd say around 50% or so. I have checked a couple spark plugs and they are good. I run regular 87 fuel (has up to 10% ethanol)

What could be causing this issue? Where should I start looking? The car has approx 303,000 KM's

Thank you

 

[Hornswaggle]

Are you getting any trouble codes/check engine light? I would suspect your throttle position sensor might have a bad spot causing loss of signal and the hesitation but if you've got any trouble codes have them checked out first. If you had high or rough idle I would also check for vacuum leaks but if bad enough that would usually trip a lean code too.

 

[johnvosh1986]

Are you getting any trouble codes/check engine light?

Nope, no check engine lights and no stored codes. Idle is fairly decent, not high. I have noticed that while sitting in drive at a light it sometimes goes up and down slightly, but nothing major.

 

[johnvosh1986]

The fuel filter was replaced after I got the car. I have only put on around 15,000 KM's since it was replaced. Transmission was serviced this year as well.

 

[sheila]

Model year/engine? Has the iac been cleaned?

 

[johnvosh1986]

It is a 1997 Ford Taurus with the 3.0L OHV Vulcan engine. I have not removed or cleaned the IAC.

 

[Automender12345]

If it is a repeatable spot in the pedal travel it could be a dead spot in the throttle position sensor or TPS. I had it on a 1990 Taurus. You can take the TPS off or leave it in place and ohm it out with a multimeter and see if it is a smooth increase in Ohms as you turn the shaft.

 

[johnvosh1986]

You can take the TPS off or leave it in place and ohm it out with a multimeter and see if it is a smooth increase in Ohms as you turn the shaft.

I took and removed the connector from the TPS and tested it with my digital multimeter and the reads looked good, looked smooth while I was increase/decrease the throttle position. I also checked all my spark plugs (pics included) and they all look decent.

 

[Automender12345]

I had a similar issue on my 1993 OHV that would stumble on acceleration. No CEL and it turned out to be a crack in the EGR flow sensor. It was a single high temperature hose on a 1993 and it was cracked. On your year it may be two hoses so it may not be the issue but worth a look in back of the intake manifold.

 

[02bullses]

Check all vacuum hoses

 

[Scambling]

Are you getting any check engine light?

 

[kekaye56]

Have you cleaned your throttle body thoroughly?